Abstract:
A seal attached to a door frame for mating engagement with a door. The seal including a first side for sealing engagement with a door edge, and a second side for sealing engagement with the door outer surface. The seal moves relative to the door from the door open position, where the seal first side is disposed at a first spaced apart distance from the door frame edge surface; to the door closed position, where the door moves the seal first side closer to the door frame edge surface. The seal further moves relative to the door from the door open position, where the seal second side is not disposed adjacent to the door outer surface; to the door closed position where the seal second side is disposed adjacent to the door outer surface and in covering relation to the door outer surface.

Description:
FIELD OF THE INVENTION 
     The invention relates to a seal intended for a base station of a radio system in particular for sealing a seam between a frame and a door or the like, the seal being at least partly made of elastic material and comprising a fastening portion by which the seal is arranged to be fastened to the frame. 
     BACKGROUND OF THE INVENTION 
     It is important to protect the radio system base station against environmental effects. As it is impossible to make a totally protective cover, for example, due to service and various connections, the electronic equipment are placed inside the protective construction comprising a door or a hatch. Such doors, covers or hatches that can be opened or closed need some kind of a seal to protect the electronic equipment against such environmental effects as dust, rain or splash water. Lip seals and hollow seals made of elastic material are typical prior art seal solutions used to tightly close the seam between the door and the frame. The function of these seals is generally based on the fact that they are compressed between the door and the frame when the door is closed. However, such a use of the seal does not provide adequate tightness for base station use in particular, since the compressive force, for example, is often insignificant. The decrease in base station size also leads to a low compression of the seal due to limited space. 
     BRIEF DESCRIPTION OF THE INVENTION 
     An object of the invention is to provide a seal so as to solve the above problems, the seal thus tightening the seam between the frame and the door using insignificant compression and low compressive force. This is achieved with the type of seal described in the preamble, characterized by comprising a first sealing portion structurally fastened to a fastening portion and arranged to turn towards the seam, when closing the door, in such a manner that as the seal fills the seam between the door and the frame at least a part of the first sealing portion is arranged to extend also over an edge of the door onto an outer surface, whereby the seal provides a continuous seal structure from the outer surface of the door to the fastening portion. 
     Several advantages are achieved with the seal of the invention. The seal, in which the sealing portion turns towards the seam and covers the area between the seal and the door so that the seal extends slightly over the door, offers more efficient protection against dust and water than prior art solutions. 
    
    
     A BRIEF DESCRIPTION OF THE DRAWINGS 
     In the following the invention will be described in greater detail in connection with the preferred embodiments with reference to the accompanying drawings, in which 
     FIG. 1 a  shows a lip seal while the door is open, 
     FIG. 1 b  shows the lip seal while the door is closed, 
     FIG. 2 a  shows a hollow seal while the door is open, 
     FIG. 2 b  shows the hollow seal while the door is closed, 
     FIG. 3 a  shows a seal of the invention while the hinged door is open, 
     FIG. 3 b  shows the seal of the invention while the hinged door is closing, 
     FIG. 3 c  shows a solution of the invention while the hinged door is closed, 
     FIG. 4 a  shows the solution of the invention while the sliding door is open, 
     FIG. 4 b  shows the solution of the invention while the sliding door is closing, 
     FIG. 4 c  shows the solution of the invention while the sliding door is closed, 
     FIG. 5 shows the seal of the invention in cross section, 
     FIG. 6 shows the seal of the invention in cross section, and 
     FIG. 7 shows the seal of the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The solution of the invention is particularly applicable for sealing a door or a hatch of a protective construction of a base station without restricting thereto. Here the door refers to doors, hatches, covers or windows that can be opened. 
     Let us first take a look at prior art solutions shown in FIGS. 1 a - 2   b.  In FIG. 1 a  the branches of a lip seal  102  forming a v-shaped cross section are spread out. The lip seal  102  is fastened to a frame  100  having an indentation for a door. In FIG. 1 b  a door  104  is closed and the door  104  presses the lip seal  102  against the frame  100  thus narrowing the v-shaped opening of the lip seal  102 . In FIG. 2 a  a hollow, tubular seal  202  is fastened to the frame  100 . The function of the hollow seal is based on the fact that the hollow seal is compressed when the door  104  is closed as shown in FIG. 3 b.    
     Let us now examine the seal of the invention in greater detail. The seal is made of elastic material as in prior art solutions and it is as easy to manufacture as prior art seals. Technical rubber, silicone, EPMD (Ethylene Propylene Diene Monomer) and many elastic plastics can function as the elastic materials. 
     According to FIG. 3 a  a seal  300  comprises a first sealing portion  302 , a fastening portion  304  by which the seal is fastened to the frame  100  and a second sealing portion  306 . The second sealing portion  306  is a lip seal in this example, but it can also be any prior art seal like a hollow seal. In this example, the door  104  comprises a hinge  106 , an edge  110 , an outer surface  112  and an inner surface  114 . The edge  110  refers to the side of the door  104  that opens in contrast to the hinged side. Although the edge  110  is separated from the rest of the door by hatching it, the edge  110  need not be structurally different from the rest of the door material. The outer surface  112  of the door  104  is in this example the side, in which direction the door opens. The inner surface  114  is the opposite side of the outer surface  112 . In FIG. 3 a  the door  104  is still open but closing. Then the edge  110  of the door  104  is close to the first sealing portion  302  or touches it. 
     In FIG. 3 b  the door  104  is nearly closed. In this example, the edge  110  of the door  104  touches the first sealing portion  302  and pushes it towards its final position. The door  104  thus controls the first sealing portion  302 . The edge  110  compresses the first side  308  of the first sealing portion  302  whereby the first sealing portion  302  turns in such a manner that the second side  310  of the first sealing portion  302  moves towards the outer surface  112  of the door  104 . 
     In FIG. 3 c  the door  104  is closed and the first sealing portion  302  efficiently seals the seam between the door  104  and the frame  100 . Then the first side  308  of the first sealing portion  302  is against the edge  110  of the door  104  at the same time as it is preferably pressed, at least partly, against the fastening portion  304  of the seal  300 . The second side  310  of the first sealing portion  302  now slightly overlaps the outer surface  112  of the door  104 . In this case, no gaps are left between the door  104  and the seal  300 , since the door  104  and the seal are tightly pressed against each other. No gaps can either be left between the seal  300  and the frame  100 , since the seal  300  is firmly fastened to the frame  100 . The second sealing portion  306  improving the sealing is a lip seal. However, although FIGS. 3 a - 3   c  show an indentation in the frame  100 , it is not, as is obvious to one skilled in the art, necessarily needed, particularly if the second sealing portion  306  is not used. The frame  100  can be made of the same or a different material than the other wall parts. What is essential to the frame  100  is that it serves the door as the frame of a corresponding opening. 
     FIG. 4 shows a solution where a door  404  does not include a hinge but where the door is, for example, a sliding door or equivalent. In this example, the door  404  comprises edges  410 , an outer surface  412  and an inner surface  414 . In FIG. 4 a  the door  404  is still open but closing. Then the edges  410  of the door  404  are close to the first sealing portions  302  or are touching it. 
     In FIG. 4 b  the door  404  is nearly closed. In this example, the edges  410  of the door  404  touch and push the first sealing portions  302  towards their final position. The door  404  thus controls the first sealing portions  302  in the same way as in the examples of FIG. 3 b.  The edges  410  compress the sides  308  of the first sealing portions  302 , whereby the first sealing portions  302  turn in such a manner that the second sides  310  of the first sealing portions  302  move towards the outer surface  412  of the door  404 . 
     In FIG. 4 c  the door  404  is closed and the first sealing portions  302  efficiently seal the seam between the door  404  and the frames  400 . Then the first sides  308  of the first sealing portions  302  are against the edge  410  of the door  404  at the same time as they are preferably also pressed, at least partly, against the fastening portions  304  of the seal  300 . The second side  310  of the first sealing portions  302  now slightly overlaps the outer surface  412  of the door  404 . Then no gaps are left between the door  404  and the seal  300 , since the door  404  and the seals  300  are tightly pressed against each other. No gaps can either be left between the seals  300  and the frames  400  since the seals  300  are firmly fastened to the frames  400 . 
     The most important feature of the invention is that, when closing, the door actively turns the first sealing portion  302  in such a way that the seal fills the seam between the door and the frame, and at least a part of the first sealing portion  302  also extends over the edge of the door onto the outer surface in order to improve the sealing. Then the seal uniformly extends from the outer surface of the door to the fastening portion and firmly closes the seam between the door and the frame. Neither dust nor water can come between the sealing portion and the frame, since the sealing portion is usually very tightly fastened to the frame. 
     FIGS. 5 and 6 show two different cross sections of the seal. They are merely examples of different shapes which are not as such important to the invention. What is important is that the seals are formed to fit the door. The seal in FIG. 5 comprises only the most essential parts of the seal of the invention. The seal comprises a first sealing portion  500  including two sides  504  and  506  forming a v-shaped groove, and a fastening portion  502 . The seal of the invention does not need to include a lip-like sealing portion as shown in FIGS. 3 a - 3   c  and  4   a - 4   c,  although it conveniently complements the invention. The fastening portion may comprise an adhesive surface  508  to facilitate fastening. FIG. 6 shows a seal comprising the same portions but with slightly rounded shapes. The seal comprises a first sealing portion  600  including two sides  604  and  606  forming a u-like groove and a fastening portion  602 . An adhesive surface  608  of the fastening portion  602  is also included in FIG.  6 . The rotating motion of the first sealing portion  500 ,  600  in relation to the fastening portion  502 ,  602  is preferably implemented using the elasticity of the seal. The seal is preferably a uniform piece made of a single material. The seal can also be composed of at least two materials, for example, so that the fastening portion  502 ,  602  is less elastic than the first sealing portion  500 ,  600 . 
     FIG. 7 is a three-dimensional picture showing the seal of the invention. The inventive seal is preferably strip-like. The seal comprises a first sealing portion  700 , a fastening portion  702 , sides  704  and  706 . In addition, as an example of various fastening methods a hole  708  from where the seal can be fastened is drawn to the fastening portion  702 . Neither a hole nor an adhesive surface is needed in the seal, but the seal can be fastened using prior art fastening methods employing adhesives or mechanical fastening. The fastening portion  702  may include the adhesive or it may be put therein during fastening. The seal can be fastened from the holes or the fastening portion  702  of the seal can be penetrated using fastening means (staple, nail, screw etc.) The fastening portion may also include mechanical fastening means that match the counterparts of the fastening means in the frame. In order to improve the efficiency of the sealing the seal  700  can be conductive, in which case it also prevents electromagnetic radiation from passing through the seal in either direction. In order to obtain a conductive seal known methods are used, for example, metal fibres, metal filament, metal lamellas or expanded metal are added into the seal material. The material as such can also be conductive. 
     Even though the invention has been described above with reference to the example of the accompanying drawings, it is obvious that the invention is not restricted thereto but can be modified in various ways within the scope of the inventive idea disclosed in the attached claims.