Abstract:
A device for lacquering or coating a substrate is disclosed. The device includes a substrate plate configured to accommodate said substrate, and one or more suction points connected to, and extending upwardly from, the substrate plate. The one or more suction points may be configured to provide a vacuum to said substrate.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of priority to German Application No. 102012100030.1, filed Jan. 3, 2012, which is fully incorporated herein by reference as though fully set forth herein. 
       TECHNICAL FIELD 
       [0002]    The present disclosure concerns a substrate plate for holding a substrate that may be lacquered or coated. 
       BACKGROUND 
       [0003]    Devices having a rotary plate and a substrate plate are used for processing, especially lacquering and/or coating of substrates. A drive is arranged beneath the rotary plate, which rotates the rotary plate and also the substrate plate via a rotational shaft. 
         [0004]    EP 1 743 220 B1, for example, discloses such a device. However, it is not disclosed here how the substrate is held on the substrate plate. 
         [0005]    Known holding methods have the drawback that they can damage an already lacquered and/or coated surface of the substrate. This is a particular disadvantage in substrates that are to be lacquered and/or coated on both sides. It is a shortcoming that a downward directed substrate surface, which is still to be lacquered and/or coated in a later work step, can already be sprayed during lacquering and/or coating of the other side. 
       BRIEF SUMMARY 
       [0006]    The task of the invention is to provide a substrate plate, which minimizes the drawbacks just mentioned or even eliminates them and the bottom of the substrate surface being lacquered is kept as pristine as possible. 
         [0007]    The features of the disclosure lead to solution of the aforementioned challenges. 
         [0008]    In typical practical examples a substrate plate includes a suction point to accommodate a substrate on its surface. This provides the advantage that the substrate is attached by suction via the suction point and can be reliably held on the substrate plate on this account. Even during rotation, acceleration and braking of the substrate plate there is no hazard that the substrate will fall down. Owing to the fact that the holding force is exerted by a suction point, the advantage is gained that a hazard of damage by holding elements, grippers, clamps or the like is at least minimized. 
         [0009]    In typical practical examples the suction plate has a spacing from a surface of the substrate plate. This provides the advantage that the substrate plate only comes in contact with the suction point so that only few contact surfaces that might lead to damage are produced. 
         [0010]    The suction point preferably has a spacing from 1 mm to 30 mm, with particular preference 7 mm from a surface of the substrate plate. This provides the advantage that a sufficient spacing is achieved, but a tube forming the suction point still has sufficient stability. 
         [0011]    In typical practical examples the substrate plate includes a number of suction points. This provides the advantage that the substrate plate is held reliably in one plane and cannot tilt. Moreover there is the advantage that only a limited holding force is required on each individual suction point because of the number of suction points. It is therefore sufficient if only a slight partial vacuum is applied to substrate plate or suction points. 
         [0012]    In typical practical examples the substrate plate includes three, four or five suction points. This is particularly advantageous because the substrate plate is reliably held by this and long lines are not produced. 
         [0013]    In typical practical examples the suction point is connected to a partial vacuum source by a channel. This provides the advantage that a partial vacuum can be applied to the suction points, producing the holding force. 
         [0014]    In typical practical examples the channels are arranged in the substrate plate. The channels are preferably arranged in one plate of the substrate plate. This provides the advantage that no additional lines or tubes must be laid. This is particularly advantageous since the substrate plate is rotated with high speed. 
         [0015]    In typical practical examples the channel is milled into one surface of the substrate plate or into one plate of the substrate plate. This provides the advantage that the channel or channels can be produced very simply. 
         [0016]    In typical practical examples a closure piece is inserted into the recess in order to seal off the channel. In this way the channel remains free. This is particularly advantageous because production of the channel is greatly simplified on this account and drilling of long holes is not necessary. 
         [0017]    In typical practical examples the suction point includes a flexible surface. This provides the advantage the suction point has not sharp edges at the locations that come in contact with the substrate which could lead to damage to the substrate. The suction point preferably includes a rubber lip that forms the flexible surface. 
         [0018]    Protection is separately claimed for use of a substrate plate in an apparatus for rotational lacquering of substrates. This provides the advantage that the substrate can be reliably held in an apparatus for rotational lacquering and/or coating. The substrate is also held in a manner that protects the back side by the design of the substrate points. 
         [0019]    In typical practical examples an inner area of the device is sealed off from the atmosphere for rotational lacquering. This provides the advantage that a co-rotating air column is formed between the substrate and the substrate plate and the effect is intensified. This prevents lacquer or coating medium from reaching the back of the substrate, which is only to be lacquered and/or coated later. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    The invention is briefly described below with reference to the accompanying drawing, in which its individual figures show: 
           [0021]    FIG.  1 —a schematic depiction of a side view of substrate plate according to the invention with a substrate; 
           [0022]    FIG.  2 —a schematic depiction of a top view of a substrate plate according to the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0023]      FIG. 1  shows a substrate plate  1  according to the invention with a substrate  2 . The substrate plate  1  includes a plate  3 , a connection site  4  and a four suction points  5 ,  6 ,  7  and  8 . 
         [0024]    The substrate  2  and plate  3  in the present practical example are designed as circular disks. 
         [0025]    In additional practical examples (not depicted) plates with rectangular, square or triangular shape are used. In principle, all plate shapes for all substrate shapes are suitable. Only the arrangement of the suction points is important. 
         [0026]    Each of the section points  5 ,  6 ,  7  and  8  has a spacing A from the surface  9  of plate  3 . This provides the advantage that the substrate  2  forms only a few support points with the substrate plate  1 . Because of this the number of contact sites that might lead to damage of the surface or the coating is reduced. 
         [0027]    Each of the suction points  5 ,  6 ,  7  and  8  is connected via a channel  10 ,  11 ,  12  and  13  to a compressed air source (not shown). The compressed air source is preferably connected to channels  10 ,  11 ,  12  and  13  and a connection site  4 . 
         [0028]    The suction points  5 ,  6 ,  7  and  8  each have a tube  15 . The length of the tube  15  determines the spacing A of the section points  5 ,  6 ,  7  and  8  and the substrate  2  from a surface  9  of plate  3 . 
         [0029]    Tube  15  includes a foot  16 . The tube  15  is fastened to the plate  3  with foot  16 . As is apparent in  FIG. 2 , the foot  16  is preferably screwed onto plate  3  with screws  17 . 
         [0030]    Each of the suction points  5 ,  6 ,  7  and  8  has a flexible surface. In the present practical example the flexible surface is formed by rubber lip  14 . The rubber lip  14  is stretched onto an upper edge of the tube  15  so that an opening  18  remains free. 
         [0031]    The channels  10 ,  11 ,  12  and  13  of a surface  9  of plate  3  are preferably milled in plate  3 . As is apparent in  FIG. 2 , the channels  10 ,  11 ,  12  and  13  are each closed by a closure piece  19 ,  20 ,  21  and  22 . This provides the advantage that the channels can be produced simply. 
         [0032]    The invention functions as follows: 
         [0033]    The substrate plate  1  is preferably used in apparatuses for rotary lacquering of substrates. For this purpose the substrate plate  1  is connected to a partial vacuum source. 
         [0034]    The substrate  2  is then placed on the suction points  5 ,  6 ,  7  and  8 . Substrate  2  is reliably held even during rotation by the applied partial vacuum. Because of the limited number and small size of the suction points  5 ,  6 ,  7  and  8  it is prevented that any already coated back side  23  is damaged. This is particularly advantage in a substrate  2  that is to be coated on both sides. 
         [0035]    By using the substrate plate  1  according to the invention in an apparatus for lacquering that is sealed relative to the atmosphere, the advantage is obtained that in the area between substrate  2  and plate  3  a co-rotating air column is formed. This prevents from lacquer or coating material from penetrating into the area between plate  3  and substrate  2 . Sprays onto the back of substrate  2  are avoided on this account. 
         [0036]    After lacquering and/or coating of a surface of substrate  2  that the partial vacuum source is switched off so that substrate  2  can be removed from substrate plate  1  with a handling unit. The substrate  2  is then rotated so that the back side  23  depicted in  FIG. 1  faces up and is placed on the suction points  5 ,  6 ,  7  and  8 . 
         [0037]    The partial vacuum source is now switched on again so that the substrate  2  is again reliably held on the suction points  5 ,  6 ,  7  and  8 . 
         [0038]    The substrate plate  1  is rotated to coat and/or lacquer the back side  23  of substrate  1  now on the top. As already described, this is very sparing for the already coated top now lying on the bottom. On the one hand, few contacts sites are present that could damage the coating. On the other hand, the co-rotating air column prevents sprays from reaching the already coated side of the substrate facing plate  3  now lying on the bottom during the second coating and/or lacquering process.