Patent Publication Number: US-2004047035-A1

Title: Binoculars

Description:
TECHNICAL FIELD OF THE INVENTION  
       [0001] The invention relates to binoculars or field glasses as defined in the preamble to claim 1.  
       PRIOR ART  
       [0002] Simple field glasses have at least two lenses, namely one lens in the front and one in the back, wherein both lenses are positioned on a joint optical axis and the rear lens functions as eyepiece. A central part extends between the two lenses, which completely encloses the beam path between the two lenses to prevent the negative influence of scattered light from the side. As a rule, field glasses of this type have two pairs of lenses and, in that case, are generally called binoculars.  
       [0003] Binoculars known so far generally have a large volume and therefore are not carried along to many events at which they would be quite useful, for example to open-air events or sports events.  
       SUBJECT MATTER OF THE INVENTION  
       [0004] Starting with this prior art, it is the object of the invention to create binoculars that can be reduced to a less voluminous state when not in use, e.g. such that they can fit into a shirt pocket or jacket pocket.  
       [0005] This object is solved with binoculars having the features as defined in claim 1.  
       [0006] The binoculars according to the invention can assume two states, namely the working position and the resting position. For the working position, the front and the rear lenses are positioned on a joint optical axis and a central part encloses the beam path in-between. For the resting position, the lenses can be pivoted out of the working position and the central part can be folded up. For this, the binoculars are designed as follows:  
       [0007] The front lens and the rear lens—in the case of binoculars the two front lenses and the two rear lenses—are held inside end walls, which are attached to a central part such that they can pivot. They can be pivoted between the working position and a rest position. The central part is designed such that its side walls can be pivoted relative to each other once the end walls have been pivoted out and the central part on the whole can be folded up. In the geometrically simplest case, the central part has at least four side walls that can be pivoted into each other, so as to form a parallelogram. In the working position, the end walls stabilize the central part, so that this part can be folded up only in the resting position, but not in the working position. The central part generally must comprise an even number of side walls to make it possible for this part to be folded completely flat.  
       [0008] According to claim 2, binoculars with sharp focusing can be created without having to relinquish the folding ability according to the invention.  
       [0009] It is particularly easy to produce binoculars as defined in the additional claim 3.  
       [0010] Binoculars according to the additional features in claims 6 or 7, in particular in connection with claim 12, can be produced very easily and are advantageous because they are produced from harmless materials. Thus, they can also be taken along to open-air events and the like without problems because they do not represent a dangerous projectile.  
       [0011] According to the additional features in claim 8, a relatively good accuracy can be achieved for the working position.  
       [0012] The additional features defined in claim 10 show the well-known field glasses with two lenses in the working position.  
       [0013] An embodiment with the additional features as described in claim 11, in particular, results in binoculars having the features of claim 3, which can be easily produced.  
       [0014] Additional preferred embodiments follow from the further dependent claims.  
       [0015] Since the object is to create binoculars that are lightweight, easy to handle and in particular made of a harmless material, the use of plastic lenses is generally preferred. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0016] The invention is explained in the following with an exemplary embodiment and reference to the Figures, which show in:  
     [0017]FIG. 1 The components of binoculars in the unassembled state;  
     [0018] FIGS.  2 A-K The assembly of the binoculars;  
     [0019]FIG. 3 The conversion of the binoculars from the resting position to the working position;  
     [0020]FIG. 4A A longitudinal section through the binoculars in the working position;  
     [0021]FIG. 4B Binoculars held in a hand;  
     [0022]FIG. 5 Alternative embodiments of the binoculars;  
     [0023]FIGS. 6A, B The binoculars with additional holding elements. 
    
    
     [0024] The binoculars according to the invention and the present exemplary embodiment are assembled from a total of four parts, the first blank A, the second blank B, the rear lens pair  25  and the front lens pair  35 . As shown in the following, the outer sleeve  16  is formed using the first blank A, which comprises the outer side walls  16 A to  16 F and the front end wall  30  that is formed as one piece with the outer sleeve  16 . In an analog manner, the second blank B is used to form the inner sleeve  12  with the inner side walls  12 A to  12 F and the rear end wall  20 , which also forms an integral part of the inner sleeve  12 . The rear end wall  20  supports the rear lens pair  25 .  
     [0025]FIG. 2A shows that initially the rear lens pair  25  is inserted into the rear end wall  20 . The rear end wall  20  is designed as double wall, so that when folding over the rear section  20 ′ of the rear end wall the rear lens pair  25  is completely enclosed. The rear section  20 ′ is provided with an adhesive section  20 ″ for the fixation.  
     [0026] In the next step, the inner sleeve  12  is formed along the folding lines shown with dashed lines, so that the inner side walls  12 A to  12 F are created. The inner sleeve  12  is provided with an adhesive section  12 ′ for the fixation. For the later fixation of the rear end wall  20  in the working position, the upper portion of the inner end wall  12 F has a fixation slot  13  and the rear end wall  20  has a fixation nipple  21 .  
     [0027] The outer sleeve  16  with the front end wall  30  is formed in an analog manner from the first blank A (see FIGS. 2E to  2 H).  
     [0028]FIGS. 2I to  2 K show that the inner sleeve  12  is pushed into the outer sleeve  16  until the finished binoculars are in the resting position.  
     [0029]FIGS. 3A to  3 D show how the binoculars are changed from the resting position to the working position. Initially, the inner sleeve  12  is pulled out of the outer sleeve  16 , wherein the telescoping path is delimited by a projection  13  on the inner sleeve that engages in a slot  17  of the outer sleeve. Following this, the side walls of the central part  10  are pushed together, so that the upper and lower side walls move away from each other to form a hollow space (see FIG. 3B). Finally, as can be seen in FIG. 3C, the end walls  20 ,  30  are pivoted to a position in which they are perpendicular to the side walls and are secured there with the aid of the fixation slots  13  and the fixation nipple  21 . The binoculars are then “closed” and are in the working position where respectively a front and a rear lens are positioned on an optical axis. To facilitate the fold-up and fold-out operations, both sleeves are provided with catches  11 . For folding up the binoculars, these steps are reversed.  
     [0030] The inner and the outer sleeve can be displaced relative to each other by a specific axial distance X, so that they can be focused sharply, e.g. as shown clearly in FIG. 4A. For a simple embodiment, it would also be conceivable to form the complete binoculars as one piece, to omit the telescoping ability and to select a continuous infinite adjustment of the lenses.  
     [0031] Four alternative embodiments of the binoculars are shown in FIG. 5, respectively in a view from the front and a perspective view. The essential difference between the variants is that the central part of each variant is shaped differently and, in particular, has a different number of side walls and/or differently shaped side walls. However, the shape of the central part  10  must always be selected such that it can be folded up. For example, a triangular cross section would not be possible.  
     [0032] Since the binoculars at hand are to be used mainly for open-air and sports events, it makes sense if a holding device is also provided, e.g. in the form of rubber bands, so that the binoculars can be positioned securely on the head and do not have to be held with the hands. Since the binoculars in particular can also be made of cardboard, they are lightweight enough not to require strong holding forces, thus making them relatively comfortable to wear. A holding element of this type is shown in FIGS. 6A and 6B and is provided with two rubber bands  41 ,  42 , arranged on the inner sleeve  12 , which can be snapped together with a snap fastener  44   a ,  44   b  to hold the binoculars against the head of the user (FIG. 6B). A piece of string  48  is furthermore attached to the ends of the rubber bands  41 ,  42 , such that the binoculars can be placed around the neck.  
     [0033] The above-described exemplary embodiment is primarily configured for an embodiment with cardboard and thus has preset bending edges. However, the blanks A and B can also be produced as injection-molded parts with thinned-out bending edges.