Abstract:
A spring-loaded hinge ( 1 ) is suggested for eyeglasses with a center part and bows surrounding eyeglass lenses, with at least one spring element ( 41 ), at least one hinge element ( 9 ) having a hinge eye ( 11 ) and with a locking element ( 7 ). It is characterized in that the locking element ( 7 ) consists of elastically deformable flat material, especially of a strip of sheet metal, the locking element ( 7 ) has a locking tab ( 37 ), and the flat material has a hole ( 81 ) for holding a spring pin ( 15 ).

Description:
RELATED APPLICATIONS  
         [0001]    The present application claims priority to German Patent Application 10204821.5, filed Feb. 1, 2002.  
         DESCRIPTION BACKGROUND  
         [0002]    The invention relates to a spring-loaded hinge for eyeglasses [according to the preamble of Claim 1].  
           [0003]    Spring-loaded hinges of the type mentioned here are known. They are used to improve the closing and opening behavior of eyeglass bows and to increase the flexibility and wearing comfort of the eyeglasses. Usually such hinges have at least one hinge element having a hinge eye, a locking element and at least one spring element. It is conceivable that the locking element is in engagement with the housing of the spring-loaded hinge and serves as a stop for the spring element. In this way, it is possible to house and to stop the hinge element in the housing, and thus also the hinge eye, with spring loading.  
           [0004]    In addition, symmetrical locking elements are known for this that have, for example, two locking elements that are designed the same that can be brought into engagement with the housing. However, it has been found that the locking devices require a relatively large amount of construction space.  
           [0005]    In order to avoid these disadvantages, an attempt was made to use locking elements with only one locking device. However, it was found in this process that because of the holding forces, these had a tendency to jam with a spring pin, which induced high bending moments in it and leads to a failure of the spring-loaded hinge during use due to jamming.  
           [0006]    In order to avoid this, asymmetrical locks are known that have a tube-shaped recess in which the spring pin can be mounted. Finally, it has been found that in spite of the tube-shaped recess, the tendency to jam remains and a certain wear continues to occur. In addition, it has been found that additional construction space has to be provided in the longitudinal direction of the spring pin for the guide element. As a result, there is a comparably thin, but longer, spring-loaded hinge.  
         SUMMARY OF THE INVENTION  
         [0007]    Therefore, the task of the invention is, starting from the state of the art, to produce a spring-loaded hinge of the type named at the beginning, which prevents this disadvantage.  
           [0008]    To solve this task, a spring-loaded hinge for eyeglasses is suggested that has [the characteristics named in Claim 1. This is distinguished by] an elastically deformable locking element that consists of flat material, especially of a strip of sheet metal, which has a locking tab and by the fact that the flat material comprises an opening to hold a spring pin. This offers the advantage that the flat material can be used as a stop for the spring element and thus to absorb the spring forces. In this process, the flat side of the same can be turned toward one end of the spring element so that the locking element requires very little construction space in the lengthwise direction of the spring-loaded hinge, which makes possible a spring-loaded pin that is shorter overall.  
           [0009]    An embodiment of the invention is preferred that distinguishes itself in that the locking element has a guide area. This guide area can advantageously cooperate with another guide area of the hinge element of the spring-loaded hinge, whereby the hinge element can be stabilized. In addition, forces can be introduced in the locking element through the guide area that additionally stabilize it and hold it in a desired position, which prevents it from jamming with the hinge element. In addition, the wear occurring due to friction can be minimized on the locking element and the hinge element.  
           [0010]    Another preferred embodiment of the invention is characterized in that the guide area can be made of a strip of material. This offers the advantage that the surface of the strip can be used as a guide area without complicated machining.  
           [0011]    An embodiment of the invention is especially preferred that is characterized in that the locking element is designed as a part produced with a stamping/bending machine. A locking element such as this can be manufactured with few work steps from standard flat material and is therefore especially economical and cost-effective.  
           [0012]    Further advantages result from the remaining subclaims. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    The invention will be explained in the following in more detail using the drawings. They show:  
         [0014]    [0014]FIG. 1 shows a side view of partially cut-away parts of the spring-loaded hinge with hinge elements not mounted;  
         [0015]    [0015]FIGS. 2 and 3 show side views of the spring-loaded hinge shown in FIG. 1 in assembled condition in various function positions;  
         [0016]    [0016]FIG. 4 shows a top view of a hinge element with a spring;  
         [0017]    FIGS.  5  to  7  show various views of a spring-loaded hinge housing and  
         [0018]    FIGS.  8  to  10  show various illustrations of a locking element. 
     
    
     DETAILED DESCRIPTION  
       [0019]    [0019]FIG. 1 shows, in side view, parts of a disassembled spring-loaded hinge  1 , whereby a first hinge element  3  and a housing  5  are illustrated in longitudinal cross section. A locking element  7  can also be seen as well as a second hinge element  9 , which has a hinge eye  11 , a guide area  13 , a spring pin  15  that is used for guiding a spring shown in FIGS. 2, 3 and a stop  17 .  
         [0020]    The hinge eye  11  and the guide area  13  in this embodiment exhibit two common surfaces that run parallel to the plane of the image, of which one surface  19  is visible. The surface  19  can interact, at least in some areas, with gliding surfaces of housing  5  that are not visible here. Gliding surfaces  21 ,  23  of housing  5  can be seen that are mounted parallel to the gliding surfaces that are not seen and are partially covered by the second hinge element  9  and the locking element  7 . The second hinge element  9  can be mounted so that it glides in its lengthwise direction on gliding surfaces  21 ,  23  of housing  5  and on the surface of the second hinge element  9  parallel to surface  19  and the gliding surfaces of housing  5  and surface  19 , each of which is not visible.  
         [0021]    In addition, the guide area  13  of the second hinge element  9  and housing  5  have other guide surfaces  25 ,  27 ,  29  and  31  that are perpendicular to the image plane. In this process, the guide surfaces  31  and  25  are assigned to each other and cooperate. The guide surface  29  can cooperate with another part of the eyeglasses that is not shown here, e.g. a bow, on which the spring-loaded hinge  1  is mounted. The guide surface  27  cooperates with a guide area  33 , which is designed here as a strip of material and has another guide surface  35 , of locking element  7 .  
         [0022]    Locking element  7  has a locking tab  37  that engages in a locking recess  39  of housing  5  and can latch there.  
         [0023]    [0023]FIGS. 2 and 3 show the spring-loaded hinge  1  in FIG. 1 in various functional positions. Common parts are provided with the same reference numbers so that to this extent, reference is made to FIG. 1.  
         [0024]    [0024]FIG. 2 shows the spring-loaded hinge  1  in open condition, in that a center part of attached eyeglasses assumes an angle of approximately 90°, preferably approximately 88°, with the eyeglass bows. This position thus corresponds to the open condition of the eyeglasses as they are worn.  
         [0025]    [0025]FIG. 3 shows the spring-loaded hinge  1  in an excessively open position. In this case, the center part of the eyeglasses and the associated eyeglass bows are at an obtuse angle to each other. This position makes sense when taking off and putting on the eyeglasses.  
         [0026]    In both illustrations, the locking tab  37  contacts the locking recess  39  of housing  5 . Locking element  7  is pressed by a spring  41 , which is located between it and stop  17 , against the locking recess  39  of housing  5 . The transmission of force occurs, starting from the locking recess  39  of housing  5 , over the locking tab  37  of locking element  7  to the pre-stressed spring  41  that contacts stop  17 , by way of spring pin  15  of second hinge element  9  to its hinge eye  11 , which generally transfers the force to one or two other hinge eyes of the first hinge element  3  by way of a hinge joint  43  of spring-loaded hinge  1  formed by a screw, which ultimately stops at housing  5  in an area  45  of the other hinge eyes as can be seen in FIG. 2, i.e. introduces the opposing force into housing  5  of spring-loaded hinge  1 .  
         [0027]    [0027]FIG. 3 shows the spring-loaded hinge  1  in a function position in which the eyeglass bows are opened extra wide, i.e. more than 90°. Also indicated are eyeglass parts  47  and  49 , whereby e.g. the eyeglass part  49  can be an implied eyeglass bow and eyeglass part  47  can be an implied center part—or vice versa—of the eyeglasses. Eyeglass parts  47 ,  49  are connected in a suitable manner, e.g. by welding, gluing, soldering, bonding, riveting, etc. to spring-loaded hinge  1  and thus are hinge-mounted on it.  
         [0028]    The function illustration according to FIG. 3 corresponds to the maximum run-out of eyeglass parts  47 ,  49 , whereby the spring windings of spring  41  are blocked and the eyeglass parts  47 ,  49  assume e.g. an obtuse angle of 157° to each other. This run-out of the eyeglass parts makes possible a large spreading of the eyeglass bows so that the eyeglasses can comfortably be put on and taken off. In this function position, the opposing force of spring  41  is transferred maximally to second hinge element  9 , which transfers it to the first hinge element  3 . It can also be seen that the opposing force in this function position is transferred by way of eyeglass parts  47 ,  49 , at an area  45 ′, from the first hinge element  3  over the eyeglass part  49  to housing  5 .  
         [0029]    Hinge joint  43  of spring-loaded hinge  1  has a point of rotation M, at a distance from which area  45 ′ is arranged. Because of the spring forces transferred, there is a torque which, starting from the function position shown in FIG. 3, increases the angle of eyeglass parts  47 ,  49  in this embodiment by approximately 157° to approximately 182°, which corresponds to the function position shown in FIG. 2. The function position shown in FIG. 2 corresponds to an equilibrium position, whereby spring  41  has a maximum length and the spring force is introduced over the areas  45 ,  45 ′ from first hinge element  3  into housing  5  such that there is equilibrium of moment. First hinge element  3  thus contacts the front side of the housing so that a defined function position of all hinge elements with respect to each other results.  
         [0030]    For closing the eyeglasses, the angle can be further increased until the eyeglass bows lie approximately parallel to the center part of the eyeglasses. When the eyeglasses are worn, the eyeglass parts  47 ,  49  can assume an angle to each other that lies between 157° and 182°, i.e. between the function illustrations according to FIGS. 2 and 3. In this way, the eyeglasses can adjust to the respective wearer and are at a slight pressure due to the deflection of the spring force on the eyeglass bows that was just described, i.e. because of the induced torques, which makes possible especially good wearing comfort and good fit of the eyeglasses.  
         [0031]    It can also be seen from FIG. 3 that even with the maximum run-out angle of eyeglass parts  47 ,  49  the second hinge element  9  is optimally guided. What is important here is that even with maximum run-out, i.e. if spring  41  is blocked according to FIG. 3, the individual guide surfaces are still in contact to an adequate extent.  
         [0032]    In detail, in each case parts of the first guide surface  24  of second hinge element  9  cooperate with the fourth guide surface  31  of housing  5  and second guide surface  27  of second hinge element  9  with the fifth guide surface  35  of guide area  33  of locking element  7  and the third guide surface  29  of second hinge element  9  with a sixth guide surface  51  of eyeglass part  49 .  
         [0033]    Second hinge element  9  is thus mounted so that it can glide on all three areas and is thus protected against distortion and jamming because of the moments induced by the opening and closing of the eyeglass bows. In addition, gliding surfaces  21 ,  23  cooperate laterally with the guide area  13  of second hinge element  9 . This stabilizes the second hinge element  9  with respect to housing  5  against unintentional turning around the center axis of spring pin  15 . This means that the spring-loaded hinge  1  is adequately stabilized against forces that occur during incorrect opening and closing of the eyeglass bows and during wearing of the eyeglasses. Because of the support of locking element  7  by the guide and sliding surfaces, pull-out forces up to 250 N can be achieved. In addition, jamming of the locking element is securely prevented.  
         [0034]    In addition, it becomes clear that guide area  33  of locking element  7  supports the second hinge element  9 . At the same time, second hinge element  9  that supports itself on guide area  33  pushes down locking element  7 , i.e. pushes it against eyeglass part  49 , so that it contacts it securely and thus remains securely positioned in spite of the high spring forces that are introduced into locking element  7  by spring  41 . Guide area  33  of locking element  7  thus additionally acts as a support area for the second hinge element  9  as well as holding down locking element  7  and/or securing it against rotation. This means that during the high forces that can occur on spring  41  when it is blocked can be transferred to and/or absorbed by locking element  7  without jamming or turning and thus without damaging spring pin  15 . Locking element  7  is thus held secure against rotation in all function positions of the spring-loaded hinge  1  so blocking of spring pin  41  is securely prevented.  
         [0035]    Gliding surfaces  27  and  29  of second hinge element  9  transition into each other over a step  53 , whereby the height of step  53  corresponds to the thickness of guide area  33  of locking element  7 . This means it is insured that the guide surfaces  51  and  29 , and  35  and  27 , can be in contact uniformly with each other.  
         [0036]    Second guide surface  27  of hinge element  9  is limited by another step  55 , where the height of guide area  13  of hinge element  9  is reduced to the thickness of spring pin  15 . On its reduced side, guide area  13  has a stop  57  at which it transitions into spring pin  15 .  
         [0037]    Stop  57  and/or step  53  of hinge element  9  can contact locking element  7  and/or one end  58  of guide area  33  of locking element  7  for mounting the spring-loaded hinge  1  so that it can be compressed into the housing  5  by means of second hinge element  9 . To do this, locking element  7  is elastically deformed in the area of locking tab  37  so that it comes to rest in the area of a third step  59 , at which the guide area  13  is reduced, as seen from above. During introduction of the second hinge element  9  into housing  5 , a top end  61  of locking element  7  glides along fourth guide surface  31  of housing  5  until the locking tab  37  engages in the locking recess  39  of housing  5 . In this process, care must be taken that locking element  7  can be introduced far enough into housing  5 . FIG. 1 shows locking element  7  and the second hinge element  9  in an end position, whereby it is introduced as far as possible into housing  5 . Preferably, locking element  7  can be introduced 0.2 mm further into the housing as the final locking position, at which the top end  61  comes into contact with locking recess  39 , as shown in FIGS. 2 and 3.  
         [0038]    Spring-loaded hinge  1  can thus be pre-assembled by simply pre-assembling the second hinge element  9  and introducing it into housing  5 . In a second step, the first and second hinge elements  3 ,  9  can be connected to each other in the area of hinge joint  43 .  
         [0039]    [0039]FIG. 4 shows second hinge element  9  with the pre-assembled locking element  9  and spring  41  in top view. Common parts are provided with the same reference numbers so that to this extent the description refers to the preceding figures. The guide area  13  with first guide surface  25  that is reduced at step  59  can be recognized. In the area of the reduction of guide area  13 , locking element  7  with locking tab  37  is located. The top end  61  of locking tab  37  is rounded in an arc. As a result, the locking recess can also have an appropriately rounded contour. This makes possible an especially good engagement of locking element  7  in housing  5 . However, other shapes of recesses are also conceivable and shapes of latching means that engage in them. What is important here is that they engage securely with each other and thus ultimately locate the second hinge element  9  in housing  5 .  
         [0040]    FIGS.  5  to  7  show various views of housing  5 . Common parts are provided with the same reference numbers so that to this extent the description refers to the preceding figures.  
         [0041]    On the underside  65 , housing  5  can have weld buttons  63  with which it can be welded to one of eyeglass parts  47 ,  49 .  
         [0042]    Housing  5  has a recess formed in the longitudinal direction of the housing as hole  67  into which the pre-assembled second hinge element  9  can be placed.  
         [0043]    A partial cutaway view of housing  5 , as shown in FIG. 5, and the longitudinal cross section in FIG. 6 show that a groove  69  with an internal width that is less than that of the diameter of hole  67  is placed at the opened side of the hole from below into the housing  5 . In the area of groove  69 , housing  5  has gliding surfaces  21 ,  23  and other gliding surfaces  21 ′,  23 ′ and the fourth guide surface  31 . Groove  69  thus corresponds in its dimensions to guide area  13  of second hinge element  9 , which can be placed in it and is thus mounted in it so that it can slide. Second hinge element  9  can thus be slid along the lateral limiting surfaces of groove  69  running in longitudinal direction in housing  5 , in axial direction of spring pin  15 . The locking recess  39  of housing  5  can also be seen, which in this embodiment is designed so that it is circular. In this way, it can especially easily be placed in housing  5  as a blind hole.  
         [0044]    In FIG. 6, it can be seen that hole  67  of housing  5  has a chamfer  71  that serves as an aid for introduction of second hinge element  9  into housing  5 .  
         [0045]    On its top side, as can be seen in FIG. 7, the housing gets narrower along surfaces  73 ,  75 ,  77 ,  79 . It is advantageous that in the area of groove  69 , where the highest forces are transferred, housing  5  is correspondingly designed at its widest, i.e. most stable. In addition, the narrowing running to the right from the opening of hole  67  achieves an attractive and slim visual appearance of the spring-mounted hinge  1 .  
         [0046]    FIGS.  8  to  10  show various illustrations of locking element  7 . Locking element  7  has an opening  81  that can be designed as a punch or drilled hole in which spring pin  15  of second hinge element  9  can be placed.  
         [0047]    Top end  61  of locking tab  37  has a contact surface  83  that is curved here and that is adapted to the surface of the blind hole of locking recess  37  of housing  5 . In this process, the top end  61  is designed with an arc shape and provided with a bevel that runs over the entire width of locking element  7 .  
         [0048]    The angle of the bevel corresponds to a bending angle that locking tab  37  assumes with respect to locking recess  39 , so that locking tab  37  securely contacts the wall of locking recess  39 .  
         [0049]    It is advantageous that housing  5  has a locking recess  39  that is exactly adapted to the top end  61  of locking tab  37 . This means that with the help of locking element  7 , hole  67  of housing  5  can be closed and spring  41  and spring pin  15  are protected from contamination and any fluids that could possibly penetrate.  
         [0050]    As can be seen in FIG. 9, the locking element is manufactured of flat material, especially as a part that has two bends  85  and  87  and is produced with a stamping/bending machine. The bending angle of bend  87  is approximately 90° here. At bend  85 , locking element  7  is bent by an obtuse angle, which is preferably approximately 110°. Thus the angle in the summit point of the bevel that is adapted to the area of the hole in locking recess  37 , which forms contact surface  83 , is preferably approximately 20°.  
         [0051]    In FIG. 10, which shows locking element  7  in the perspective of FIG. 8 but not in bent condition, the fifth guide surface  35  of guide area  33  can be seen. Fifth guide surface  35  and the other guide surfaces of spring-mounted hinge  1  can be provided with a special sliding coating. In addition, the material of the locking element  7  can be selected in such a way that it cooperates especially well with the material of guide area  13  and/or has especially good gliding properties, i.e. has a low coefficient of friction with respect to guide area  13 .  
         [0052]    In the area of hole  81 , the strip-shaped material of locking element  7  has an expansion zone  89  that is preferably designed with a ring shape and is adapted to the diameter of hole  67  for sealing the spring mechanical parts. At the expansion zone  89  that surrounds hole  81 , the spring  41  can come to rest from one side and step  57  of second hinge element  9  can come to rest on the other side. Thus, it is clear that the thickness of expansion zone  89  directly influences the construction length-with the same functionality-of spring-mounted hinge  1 .  
         [0053]    The expansion zone  89 , that is preferably ring-shaped, can also be manufactured of flat material, especially a strip of sheet metal of locking element  7 , e.g. by stamping, which makes possible a spring-mounted hinge  1  that has a short structure.  
         [0054]    In the further development according to FIG. 10, it can be seen that the locking element  7  has a strip-shaped section on both the right and left sides of hole  81 , whereby a first strip-shaped section makes guide area  33  and a second strip-shaped section makes the locking tab  37 . In this embodiment, the strip-shaped section of guide area  33  is longer than that of locking tab  37 . It is also conceivable to provide these with equal length or in reverse length relationships.  
         [0055]    Thus, it is conceivable to reduce guide area  33  of the locking element to such an extent that it serves only for stabilizing it. In this case, the third guide surface  29  could be enlarged accordingly and be used to guide second hinge element  9  in housing  5 .  
         [0056]    In the named embodiment, second hinge element  9  has a hinge eye that cooperates with one or two other hinge eyes of first hinge element  3 . It is conceivable to reverse this relationship or even provide an optional combination of hinge eyes that cooperate with each other.