Abstract:
A protective case for optical devices such as binoculars, telescopes, night vision devices or field glasses, which is made of a thermoformable plastic such as a thermoplastic, to at least partly cover the optical device, thereby protecting the latter from environmental influences such as solar radiation, moisture and mechanical shocks, while guaranteeing access to the preferable functions of the device and at the same time being of a light and easily processable material.

Description:
RELATED APPLICATIONS  
       [0001]     This application claims priority to German Utility Model 203 12 522.3 filed Aug. 13, 2003, the teachings of which are incorporated herein by reference.  
       FIELD OF THE INVENTION  
       [0002]     The present invention relates to a protective case for optical devices, in particular telescopes, binoculars, night vision devices or field glasses.  
       BACKGROUND OF THE INVENTION  
       [0003]     Optical devices are frequently used in different places and must therefore be transported. It is thus important that the optical devices are effectively protected from damage by external influences such as shocks, vibrations, moisture or scratching. In particular when telescopes are used for observations of nature, it has to be taken into account that the protective case may be exposed to environmental influences such as rain, sand or solar radiation over quite long time periods. Apart from high resistance to external environmental influences, such protective cases for optical devices should also have as little weight as possible in order to increase the ease of use, and should permit the case to be removed and put on fast and quietly. The latter point of view is important in particular when observing animals in the wild. Further, economical production of the case presupposes that the materials used can be processed without problems and without great effort.  
         [0004]     Protective cases for observation telescopes are known that have a tubular form and are made of textile materials or leather. However, these conventional materials frequently have the disadvantage of either being difficult and thus cost-intensive to process, or only permitting a weight saving at the expense of mechanical stability and resistance to environmental influences. Also, such cases are frequently so constituted that the device cannot be completely used within the case, in particular because not all functional parts of the optical device are accessible from outside in the case. Complete removal of the protective case can take considerable time, however, and cause disturbing noises that are undesirable in particular when observing animals.  
         [0005]     Further, protective cases for telescopes are known that have covers for eyepieces and objectives at their ends. Here, too, these covers are so constituted that frequently they cannot be removed from their original position quietly or, after being removed from the protective initial position, they disturb the use of the optical device, e.g. because they are fastened to the case by straps and hang down loosely after removal.  
         [0006]     The present invention is therefore based on the problem of providing a protective case for optical devices that offers optimal protection from external influences such as shocks, vibrations, scratching as well as environmental influences such as moisture and solar radiation, while having as little weight as possible. Further, it is a problem of the present invention to design the protective case so as to permit fast and quiet use of preferably all functions of the optical device. Furthermore, the present invention is intended to solve the problem of providing the protective case made of a material that can be processed into any desired forms without problems even in large quantities.  
       SUMMARY OF THE INVENTION  
       [0007]     These inventive problems are solved by a protective case ( 1 ) for optical devices which comprises a thermoformable plastic ( 2 ) preformed so that it at least partly encases the optical device. Thermoformable plastics are plastics that can be converted to a softened state under the action of heat and then be preformed into a desired structure by suitable shaping methods. Suitable plastics are thermoplastics. In a preferred embodiment, the thermoformable plastic comprises ethylene vinyl acetate (EVA). Particularly preferably, the plastic comprises ethylene vinyl acetate foam, backed with bielastic materials. The inventive thermoformable plastic ( 2 ) has low weight and a good impact and shock absorbing effect. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0008]     For easier understanding, some inventive embodiments will be explained in more detail in the following with reference to the enclosed figures, in which:  
         [0009]      FIG. 1   a  shows the protective case ( 1 ) without protecting caps ( 5 );  
         [0010]      FIG. 1   b  shows the protective case ( 1 ) according to  FIG. 1   a  but turned 90°;  
         [0011]      FIG. 2  shows the protective case ( 1 ) in a linear arrangement with the protecting caps ( 5 );  
         [0012]      FIG. 3  shows the protective case ( 1 ) according to  FIG. 2  but with a protecting cap ( 5 ) swiveled by 90°; and  
         [0013]      FIG. 4  shows the protective case ( 1 ) in an angled arrangement with a protecting cap ( 5 ). 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0014]     The thermoformable plastic ( 2 ) can be provided at first as a flat plastic surface out of which a suitable form is punched which is then thermoformed. Shaping of the thermoformable plastic can be done using common shaping methods, e.g. hot pressing.  
         [0015]     The shaping methods are carried out at temperatures that are high enough to convert the plastic used to a softened state. When ethylene vinyl acetate is used, shaping is done at a temperature in the range of 100° C. to 250° C., preferably 150° C. to 200° C.  
         [0016]     The inventive thermoformable plastic ( 2 ) preformed so as to at least partly encase an optical device contained in the case is easy to process and permits the production of any desired structures. This permits the form of the protective case ( 1 ) to be adapted optimally to that of the optical device. In a preferred embodiment, the thermoformable plastic ( 2 ) is so preformed as to fit closely at least on a partial area of the optical device. This causes the optical device to be optimally fixed within the protective case ( 1 ), thereby avoiding a disturbing shift and a resulting change in already effected device adjustments during transport.  
         [0017]     The inventive protective case ( 1 ) can be adapted to any optical devices due to the thermoformable plastic ( 2 ). It is preferably a protective case for telescopes, binoculars, night vision devices or field glasses.  
         [0018]     In accordance with a preferred embodiment, the thermoformable plastic ( 2 ) is at least partly coated with an elastic textile material ( 3 ). The coating with a textile material increases the protective effect of the case vis-à-vis environmental influences. The elasticity of the textile material ( 3 ) further enables the protective case ( 1 ) to adapt better to deformation forces acting thereon, and makes it more resistant to mechanical loads. The textile material ( 3 ) can be formed either as a woven or as a knit. Bielastic wovens are preferred. Suitable textile materials ( 3 ) can comprise polyester and/or polyamide. If the textile material ( 3 ) is exposed to a relatively high temperature over a certain time period during production, polyester is preferred.  
         [0019]     The thermoformable plastic ( 2 ) can be preformed into any desired structures with consideration of the optical device to be received. In a preferred embodiment, the protective case is substantially cylindrical and has at least one open end ( 4 ), preferably two open ends ( 4 ). The open ends ( 4 ) permit e.g. a cylindrical optical device with an objective and eyepiece to be used without removing the protective case ( 1 ).  
         [0020]     Alternatively, the thermoformable plastic ( 2 ) can encase the optical device completely, if the protective function of the case is to the fore and the optical device is to be removed completely from the protective case ( 1 ) for use.  
         [0021]     In a preferred embodiment, the protective case ( 1 ) has tape-sewn suspension loops in which a carrying strap ( 11 ) can be hung. Preferably, three suspension loops ( 12 ) are provided on the outside of the case.  
         [0022]     In accordance with a preferred embodiment, protecting caps ( 5 ) can be mounted at open ends ( 4 ) of the protective case ( 1 ). Said caps ensure e.g. protection of objective and/or eyepiece of the optical device. The protecting caps ( 5 ) are preferably connected detachably with the protective case ( 1 ), so that they can be removed completely when required. For this purpose an opening tab ( 9 ) can be provided on the protecting cap ( 5 ), which is then removed fast and quietly by simply pulling on a tab.  
         [0023]     According to the invention the protecting caps ( 5 ) can likewise comprise a thermoformable, preformed plastic ( 2 ′). Preferably, the plastic is coated at least partly with an elastic textile material ( 3 ′). In a preferred embodiment, the same thermoformable plastic and the same elastic textile material are used for the protective case ( 1 ) and the protecting cap(s) ( 5 ).  
         [0024]     According to the invention, the protecting caps ( 5 ) can have a zipper ( 10 ). Preferably, the zipper extends continuously along one longitudinal side of the protecting cap, the closed end of the protecting cap and the opposite longitudinal side, so that the cap ( 5 ) can be opened or closed over this total length by operation of the zipper.  
         [0025]     The edges of both the protective case ( 1 ) and the protecting caps ( 5 ) can be tape-sewn, thereby increasing the durability.  
         [0026]     Further preferred embodiments are disclosed in the dependent claims.  
         [0027]      FIG. 1   a  and  FIG. 1   b  show a protective case ( 1 ) shaped cylindrically at least in partial areas, without protecting caps ( 5 ). Preferably, the protective case is substantially cylindrical. The protecting caps ( 5 ) can be fastened to the protective case later via snap fasteners ( 6 ). The protective case ( 1 ) is made of a thermoformable plastic ( 2 ) which is preformed in a shaping method so that it can adapt in as tightly fitting fashion as possible to the structure of the optical device to be received. The plastic ( 2 ) is coated on both sides with an elastic textile material ( 3 ). The three-layered structure is indicated schematically in  FIG. 1   b.  Said textile material ( 3 ) can extend over the total plastic surface. Preferably, the textile material ( 3 ) comprises a bielastic textile woven, which can also adapt to greatly deformed and curved surfaces due to its high elasticity present at least in two directions in space.  
         [0028]     Besides the openings ( 4 ) at the end of the protective case ( 1 ), the latter can have further openings ( 7 ) which are preferably provided so that a surface of the optical device is accessible to be used for focusing control, enlargement or attaching a tripod. This ensures comprehensive use of the device without a need to remove the protective case ( 1 ).  
         [0029]     Further, the protective case ( 1 ) can have at least one zipper ( 8 ) which is preferably provided along the cylinder wall in the longitudinal direction. In a preferred embodiment, two zippers ( 8 ) are present which are provided on opposite sides of the cylindrical case and extend along the total longitudinal direction of the cylinder wall.  
         [0030]     According to a further preferred embodiment, the protective case can have at least one further opening ( 13 ) which can serve to allow any entering water or condensed water to flow out. Further, the upper side of the protective case ( 1 ) can have provided thereon a textile band ( 14 ) which is formed into loops at its ends.  
         [0031]     According to the invention, a partial area ( 15 ) of at least one outer end of the protective case ( 1 ) can be somewhat lowered relative to the surrounding protective case surface. This lowered surface area causes a protecting cap ( 5 ) later mounted to fit the protective case ( 1 ) more snugly. By the extent of lowering one can control the extent to which the protecting cap ( 5 ) is embedded into the protective case surface.  
         [0032]      FIG. 2  shows a protective case ( 1 ) which is substantially cylindrical and has protecting caps ( 5 ) mounted at its open ends ( 4 ). The protecting caps have an open end and an opposite closed end and are suitable for example for receiving an objective or eyepiece of an optical device. Both protecting caps ( 5 ) are connected detachably to the protective case ( 1 ) by snap fasteners ( 6 ). Further, the protecting caps ( 5 ) can have tabs ( 9 ). By simply pulling on a tab ( 9 ) one can remove a cap ( 5 ) without problems.  
         [0033]     Further, the longitudinal axes of protective case ( 1 ) and protecting caps ( 5 ) extend substantially parallel. According to the invention, the longitudinal axis of the protective case ( 1 ) is so defined as to extend from an open end ( 4 ) to the opposite open end ( 4 ). The longitudinal axes of the protecting caps extend from an open end to the opposite closed end. This substantially linear arrangement of caps ( 5 ) and case ( 1 ) makes this apparatus suitable e.g. for receiving an observation telescope whose eyepiece is likewise fastened to the optical device in a linear or straight arrangement.  
         [0034]      FIG. 3  shows the protective case ( 1 ) with protecting caps ( 5 ) in a linear arrangement, whereby one of the protecting caps ( 5 ) was swiveled out of its initial position by about 90° so as to expose an end ( 4 ) originally covered by said protecting cap.  
         [0035]     According to the invention, the protective case ( 1 ) can have at least one open end ( 4 ) provided with a protecting cap ( 5 ) which swivels within a plane. Preferably, all mounted protecting caps ( 5 ) swivel within a plane. If a protecting cap ( 5 ) is connected with the protective case ( 1 ) via two snap fasteners ( 6 ), the cap ( 5 ) can be turned around the connecting axis of the two snap fasteners ( 6 ). This swiveling ability of the protecting caps ( 5 ) makes it possible for example to expose objective and eyepiece fast and quietly as soon as an object to be observed is discovered.  
         [0036]      FIG. 4  shows a protective case ( 1 ) with two protecting caps ( 5 ) whereby the longitudinal axis of the protective case ( 1 ) and the longitudinal axis of a protecting cap ( 5 ) are present in an angled arrangement to each other. The longitudinal axes can enclose an angle of 35° to 55°, preferably 40° to 50°. This embodiment makes it possible e.g. to receive a telescope or observation binoculars whose eyepiece is fastened to the optical device in an angled arrangement.