Abstract:
A protective case for an observation telescope is of inflatable design and fits closely against the outside wall ( 3 ) of the observation telescope in the inflated state.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to protective cases. More particularly, the present invention relates to protective cases for portable devices, such as an observation telescope.  
           [0003]    2. Description of the Related Technology  
           [0004]    Portable devices, such as observation telescopes are used often times in the open air, for example, for bird watching. They are thereby exposed to numerous loads such as shock or impact during transport, or environmental influences such as rain, sand or sunlight.  
           [0005]    Protective cases for observation telescopes, for example, are therefore known which have a tubular form and are made of textile materials or leather. A disadvantage of such conventional cases is that it is awkward and time-consuming to put them on and take them off the telescope. Therefore, conventional protective cases are designed or suited only for long-term storage of an observation telescope.  
           [0006]    There are other conventional protective cases made of textile materials or leather which have a tubular form and can be partially opened on the eyepiece portion, the operating portion and the objective portion of the observation telescope.  
           [0007]    One disadvantage of these designed protective cases is that their opened parts hang down during observation and thus disturb the handling of the telescope or for example, in case of wind, produce noise which can have a disturbing effect on the objects under observation. Another disadvantage is that such protective cases are also awkward to handle so that they cannot be quickly put on and taken off.  
           [0008]    In addition, as will be appreciated by one of the ordinary skill in the art, conventional protective cases offer only restricted protection from shock or impact loads on the observation telescope.  
         SUMMARY OF THE INVENTION  
         [0009]    The present invention is therefore based on the problem of avoiding the above-mentioned disa offers good protection from environmental influences and also from shock or impact.  
           [0010]    The invention is based on the finding that the above-mentioned problems can be solved by a protective case which is of inflatable design and configured to fit closely against the telescope in the inflated state.  
           [0011]    According to the invention there is provided a protective case which includes an inflatable air chamber of airtight material which fits closely against the outside wall of the portable device.  
           [0012]    First, the inventive protective case provides very good protection from shock and/or impact loads which are absorbed or cushioned by the air cushion of the case. Secondly, it achieves good protection from every kind of environmental influence such as rain, sand or sunlight. In addition, as will be appreciated by one of ordinary skill, the inventive protective case can be easily and quickly put on and taken off the portable device since this may be done in the uninflated state and the close fit of the case is produced by inflation of the air chamber.  
           [0013]    Another advantage of the protective case according to the invention is that it can be stowed in very spacesaving fashion in the uninflated state. The inventive protective case is thus optimally suited for use with an observation telescope when animal or bird watching.  
           [0014]    According to one aspect of the invention, inventive protective case preferably includes a plurality of air chambers. This ensures that the form of the case in the inflated state can be adapted very well to the outer form of the portable device.  
           [0015]    According to another aspect of the invention, inventive protective case preferably includes a smooth sheathing of robust, flexible material. This material can be for example GORE-TEX® or a like material. The protective case of this embodiment has the additional advantages that the robust, flexible material protects the air chambers from damage by outside influences, and the smoothness of the surface of the sheathing prevents dirt deposits on the case.  
           [0016]    In a presently preferred embodiment, the protective case is designed for use with an observation telescope.  
           [0017]    According to one embodiment, the inventive protective case has a tubular form, with preferably at least one end of the tube being open. The open end of the tube can protrude beyond the telescope. The open end of the tube can be made sealable. The open end can be provided on the eyepiece side or the objective side. Since the telescope has a greater diameter on the objective side, at least the objective side of the tube is preferably open to permit the telescope to be inserted. On the open side the objective can thus e.g. be covered with a protective cap.  
           [0018]    In accordance with another embodiment, the protective case likewise has a tubular form, wherein the tube has a longitudinal slit extending the full length of the tube or only partially. In this embodiments the tube can be closed at both ends, or alternatively, one or both ends can also be open and protective caps provided therefor.  
           [0019]    The inventive protective case is suitable for any portable device, especially for observation telescopes of all kinds. In particular, it is suitable both for observation telescopes in which the optical principal axis and the eyepiece axis coincide, and for observation telescopes in which the optical principal axis forms an angle with the eyepiece axis.  
           [0020]    In order to facilitate recognizability, but also for optical reasons, the protective case can be made of transparent plastic or possibly be of semitransparent or translucent design. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]    In the following enabling disclosure, the inventive protective case will be described with reference to the enclosed drawing by the example of two embodiments for an observation telescope in which the optical principal axis and the eyepiece axis form an angle, wherein:  
         [0022]    [0022]FIG. 1 shows a cross section through the protective case according to the first embodiment with the observation telescope therein;  
         [0023]    [0023]FIG. 2 shows a side view of the protective case according to FIG. 1; and  
         [0024]    [0024]FIG. 3 shows a cross section through the protective case according to the second embodiment with the observation telescope therein at the level of the objective portion. 
     
    
     DETAILED DESCRIPTION  
       [0025]    In the first embodiment, the inventive protective case is formed by a multiplicity of air chambers ( 1 ) made of airtight flexible-material such as rubber or plastic. The individual chambers ( 1 ) are lined up close together on the inner surface of a sheathing ( 2 ) and separated by partitions. The chambers ( 1 ) extend annularly around the total circumference of the protective case.  
         [0026]    The sheathing ( 2 ) can be of smooth design. The protective case is open on the side opposite the objective portion ( 4 ) of the observation telescope and protrudes beyond the objective portion ( 4 ) at a distance (a). The objective ( 4 ) is closed by a suitable protective cap ( 5 ).  
         [0027]    On the part of the protective case covering the underside of the observation binoculars in the area of the objective portion ( 4 ) a valve ( 6 ) is mounted. Said valve ( 6 ) permits the air chambers to be filled and emptied. A gap ( 7 ) is likewise provided on the underside of the protective case through which the tripod leg ( 8 ) of the observation telescope protrudes outwardly.  
         [0028]    The diameter of the protective case becomes smaller from the open end on the objective portion ( 4 ) to the eyepiece portion ( 9 ) of the telescope in accordance with the diameter of the observation telescope. In the area of the eyepiece portion ( 9 ) the protective case follows the bend of the eyepiece portion ( 9 ) relative to the objective portion ( 4 ) and operating part ( 16 ) in accordance with the angle between eyepiece axis ( 10 ) and optical principal axis ( 11 ) of the telescope.  
         [0029]    In the area of the protective case surrounding the eyepiece ( 12 ) and the eyepiece portion ( 9 ) its diameter also becomes smaller in accordance with the form of the observation telescope. The end of the protective case ( 13 ) adjacent the eyepiece ( 12 ) is likewise encompassed by the sheathing ( 2 ) of the protective case.  
         [0030]    On the sheathing of the part of the protective case adjacent the eyepiece there is a loop, cord ( 15 ) or the like (FIG. 2) in order to hold the case ( 1 ) with the telescope disposed therein.  
         [0031]    The sheathing ( 2 ) of the protective case is provided with seams ( 17 ) as depicted in FIG. 2 which follow the form of the observation telescope located in the case.  
         [0032]    The protective case can also be made of partially or completely transparent material. This permits the device located in the case to be recognized partially or completely from outside.  
         [0033]    The second embodiment of the inventive protective case is constructed analogously to the above-described first embodiment, the difference being that a longitudinal slit ( 18 ) extends over the total length of the underside of the case. The air chambers ( 1 ) are accordingly no longer constructed to be continuously annular in the cross section of the case ( 1 ), but sickle-shaped. For holding the protective case together along the longitudinal slit one can provide for example hook and loop pile (Velcro) closures at right angles to the longitudinal slit ( 18 ) which close the slit. This embodiment allows the inventive protective case to be put on and taken off especially fast since the longitudinal slit ( 18 ) provides a large opening for inserting and removing the telescope into and out of the case ( 1 ).