Abstract:
The invention relates to a pair of spectacles, comprising a viewing portion and two side arms that are each connected to the viewing portion, each side arm including a first portion and a second portion sliding relative to one another in a sliding direction between a retracted position and an extended position, said pair of spectacles being characterized in that: the first portion includes a first pair of legs extending in the sliding direction; the second portion includes a second pair of legs extending in the sliding direction; and the first pair of legs and the second pair of legs are mutually engaged.

Description:
OBJECT OF THE INVENTION 
     The invention relates to a pair of spectacles comprising a viewing portion and two side arms that are each connected to the viewing portion in a manner that offers telescoping adjustment. 
     BACKGROUND OF THE INVENTION 
     In a well known manner, such an adjustment is intended to vary the length of the side arms in order to adjust to the physiological differences between the people who wear these spectacles. Such an adjustment can also serve to increase the retention of the spectacles on the face of a specific person during certain activities in order to prevent the spectacles from shifting their position on the face or falling off in extreme cases. The invention also relates to this particularly desirable alternative when wanting to participate in athletic activities, for example. 
     There is a known conventional pair of spectacles of this type in which each side arm comprises a first portion and a second portion that slide relative to one another in a sliding direction, between a retracted position and an extended position. 
     SUMMARY OF THE INVENTION 
     The invention aims to propose a simple, robust, and aesthetically pleasing solution. 
     To achieve this, the pair of spectacles according to the invention additionally comprises the following features:
         the first portion of the side arms comprises a first pair of legs extending in the sliding direction,   the second portion of the side arms comprises a second pair of legs extending in the sliding direction,   the first pair of legs and the second pair of legs are mutually engaged.       

     Thus the legs in the first pair and the legs in the second pair guide each other in their sliding motion while preventing any relative rotational movement. 
     In another preferable feature of the invention, each side arm additionally comprises a core comprising four wings extending between the pairs of legs and connected to each other at a join line extending along the sliding direction. 
     Thus the legs can be shortened while improving the precision of the guidance between the first portion and the second portion. 
     In another feature of the invention, the core preferably extends along the sliding direction and has a cross-section perpendicular to the sliding direction that is in the form of a cross with orthogonal arms. 
     The guidance between the first portion and the second portion is thus further improved and the risk of jamming and interference with the sliding is reduced. 
     In another feature of the invention, the core is preferably attached to the first portion. 
     The simplicity of the implementation is thus increased and adjustment is facilitated. 
     In a complementary feature of the invention, the second portion is preferably retained in a releasable manner on the core, in the extended position of the side arm. 
     The use of the pair of spectacles is thus more pleasant and ergonomic. 
     In another complementary feature, the second portion is preferably retained in a releasable manner on the core when the side arm is in the retracted position. 
     The use of the pair of spectacles is thus even more pleasant and ergonomic. 
     In yet another complementary feature of the invention, the core preferably comprises at least one hook suitable for catching on a pin attached to the second portion. 
     This solution is simple, effective, and robust. 
     In another feature of the invention, the first portion and second portion are preferably of plastic, and the core is of metal. 
     This improves the robustness and ease of implementation. 
     In yet another feature of the invention, the core is preferably concealed between the first portion and the second portion when the side arm is in the retracted position. 
     This increases the aesthetics. 
     In another feature of the invention, the first portion and second portion preferably each present an outer surface that is flush with the outer surface of the other when the side arm is in the retracted position. 
     This further increases the aesthetics. 
     In another feature of the invention, the retracted position and the extended position preferably constitute two extreme sliding positions along the sliding direction, between which any relative rotational motion between the first portion and the second portion of each side arm is prevented. 
     Thus the use of the pair of spectacles is simplified and enhances its usability. 
     In another feature of the invention, the retracted position and the extended position preferably constitute two stable positions, advantageously extreme positions in the sliding direction, where the side arm is able to remain without external action. 
     In this manner the pair of spectacles offers enhanced usability for multiple users. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       Other features and advantages of the invention will be apparent from the following detailed description, referring to the attached drawings in which: 
         FIG. 1  illustrates a partially exploded perspective view of a pair of spectacles of the invention, comprising two side arms, 
         FIG. 2  is a perspective view of the pair of spectacles from the arrow labeled II in  FIG. 1 , with the side arms in the retracted position, 
         FIG. 3  illustrates the pair of spectacles of  FIG. 2  with the side arms in the extended position, 
         FIG. 4  is a cross-sectional view along the line referenced IV-IV in  FIG. 2 , at an enlarged scale, 
         FIG. 5  is a cross-sectional view along the line referenced V-V in  FIG. 1 , with the side arms in a middle pantoscopic adjustment position, 
         FIG. 6  illustrates the pair of spectacles of  FIG. 5 , with the side arms in a first extreme position of pantoscopic adjustment, 
         FIG. 7  illustrates the pair of spectacles of  FIG. 5 , with the side arms in a second extreme position of pantoscopic adjustment. 
     
    
    
     DETAILED DESCRIPTION 
     The various figures illustrate a pair of spectacles  1  essentially comprising a viewing portion  2 , a right side arm  10 , and a left side arm  110 , each arm connected to the viewing portion  2  by a hinge  20 ,  120  comprising an intermediate element  60 . 
     The viewing portion  2  extends along the front and supports the lenses (not represented). 
     The pair of spectacles  1  is symmetrical relative to a midplane, with the two side arms  10 ,  110  and the two hinges  20 ,  120  extending to each side of it. Therefore, unless otherwise stated, in the rest of the description the two side arms  10 ,  110  and the two hinges  20 ,  120  will be described simultaneously. Elements symmetrical to one another are labeled with numbers differing by  100 . 
     The side arms  10 ,  110  each comprise a front portion  12  and a rear portion  14  each arranged as the extension of the other in a sliding direction X′ and able to slide relative to each other, preferably without rotation, in the sliding direction X′ between a retracted position illustrated in particular in  FIG. 2  and an extended position illustrated in  FIG. 3 . 
     The rear portion  14 ,  114  extends in the sliding direction X′ between a free back end, intended for placement on the ears of a user, and a front end on which is arranged a pair of rear legs  26 ,  28 ;  126 ,  128  extending in the sliding direction X′. 
     The front portion  12 ,  112  extends in the sliding direction X′ between a back end, on which is arranged a pair of front legs  22 ,  24 ;  122 ,  124 , and a front end on which is arranged a tongue  11 ,  111 . 
     The side arms  10 ,  110  additionally comprise a core  40 ,  140  extending in the sliding direction X′. As illustrated in particular in  FIG. 4 , the core  40 ,  140  has a cross-section in the form of a cross comprising four orthogonal wings  42 ,  44 ,  46 ,  48 , connected to each other at a join line  50 . Each leg  22 ,  24 ,  26 ,  28  is in close contact with two adjacent wings. There is a recess  22   a ,  22   b ;  24   a ,  24   b ;  26   a ,  26   b ;  28   a ,  28   b  in each of the legs  22 ,  24 ,  26 ,  28  in order to receive the core  40  in a cavity  32  which is enclosed when the side arm  10 ,  110  is in the retracted position. Thus the core  40 ,  140  is completely hidden inside the side arm  10 ,  110  when the arm is in the retracted position, as is illustrated for side arm  110  in  FIGS. 1 and 2 . 
     The core  40 ,  140  thus extends between the pair of front legs  22 ,  24 ;  122 ,  124  and the pair of rear legs  26 ,  28 ;  126 ,  128  but also beyond, into the front portion  12  where it is attached to the front portion  12 ,  112  of the side arm  10 ,  110  by a pin  36 ,  136  as well as into the rear portion  14  where it comprises flexible front hooks  52   a ,  52   b  and flexible rear hooks  54   a ,  54   b.    
     The retracted position and the extended position constitute two extreme positions along the sliding direction X′. The retracted position and the extended position are two stable positions in which the side arms of the pair of spectacles remain when there is no external action. There can also be a slight friction to prevent undesirable sliding between the front portion  12  and the rear portion  14 . In the embodiment illustrated, as represented in  FIG. 2  as a dotted line, when the side arm  10 ,  110  is in the retracted position, the front hooks  52   a ,  52   b  releasably catch on the pins  56   a ,  56   b  fixed to the rear portion  14 . The cooperation of the front hooks  52   a ,  52   b  and the pins  56   a ,  56   b  prevents the rear portion  14 ,  114  of the side arm  10 ,  110  from sliding in the sliding direction X′ relative to the core  40 ,  140  and to the front portion  12 ,  112  of the side arm  10 ,  110 . The side arm  10 ,  110  is thus releasably retained in the retracted position. 
     However, as the front hooks  52   a ,  52   b  are flexible, by exerting sufficient force, the user can release the pins  56   a ,  56   b  from the front hooks  52   a ,  52   b  and thus cause the rear portion  14  to slide relative to the front portion  12  of the side arm  10 ,  110 . 
     In a comparable manner, as illustrated in  FIG. 3  with dotted lines, when the side arm  10 ,  110  is in the extended position, the rear hooks  54   a ,  54   b  releasably grip the pins  56   a ,  56   b . The cooperation of the rear hooks  54   a ,  54   b  and the pins  56   a ,  56   b  thus releasably maintains the side arm  10 ,  110  in the extended position. 
     Advantageously, the core  40 ,  140  is of metal, while the front portion  12 ,  112  and the rear portion  14 ,  114  of the side arm  10 ,  110  are of plastic. 
     It should also be noted that when the side arm  10 ,  110  is in the retracted position, the outer surface  16 ,  116  of the front portion  12 ,  112  and the outer surface  18 ,  118  of the rear portion  14 ,  114  of the side arm  10 ,  110  are extensions of each other with no discontinuities, the free end of the front legs  22 ,  24 ;  122 ,  124  pressing against the rear portion  14 ,  114  in the sliding direction X′ and the free end of the rear legs  26 ,  28 ;  126 ,  128  pressing against the front portion  12 ,  112  in the sliding direction X′. However, when the side arm  10 ,  110  is in the extended position, there are openings between the front legs  22 ,  24 ;  122 ,  124  and the rear portion  14 ,  114 , and between the rear legs  26 ,  28 ;  126 ,  128  and the front portion  12 ,  112 , revealing the core  40 ,  140 . 
     The length of the front legs  22 ,  24 ;  122 ,  124  and the length of the rear legs  26 ,  28 ;  126 ,  128  in the sliding direction X′ preferably corresponds substantially to the distance that the rear portion  14 ,  114  slides between its retracted position and its extended position. Thus, when the side arm  10 ,  110  is in the extended position, the front legs  22 ,  24 ;  122 ,  124  and the rear legs  26 ,  28 ;  126 ,  128  end substantially at the same level in the sliding direction X′. 
     The front portion  12 ,  112  of the side arm  10 ,  110  is assembled to pivot on the intermediate element  60 , about a folding axis Z substantially perpendicular to the sliding direction X′, between an unfolded position in which the sliding direction X′ is substantially parallel to a longitudinal direction X, as illustrated in particular in  FIGS. 1 to 3 , and a folded position in which the side arm  10 ,  110  extends substantially along the viewing portion  2 . 
     To do this, the intermediate element  60  and the front portion  12 ,  112  of the side arm  10 ,  110  are connected by a pin  30  extending along the folding axis Z. The intermediate element  60  presents two arms  62 ,  64 , extending in the longitudinal direction X, forming a slot  66  between them which receives the tongue  11 . The pin  30  is received in attachment holes arranged through the tongue  11  and the arms  62 ,  64 . 
     The intermediate element  60  is received in a housing  4  in the viewing portion  2 . The intermediate element  60  is mounted relative to the viewing portion  2  so that it can pivot about a pantoscopic adjustment axis Y, substantially perpendicular to the longitudinal direction X and to the folding axis Z, between a first extreme position illustrated in  FIG. 6  and a second extreme position illustrated in  FIG. 7 . 
     To do this, a pin  58  extending along the pantoscopic adjustment axis Y passes through a main part  72  of the intermediate element  60  and is received in an attachment hole  5  in the viewing portion  2 . 
     In order to retain the intermediate element  60 , and the side arm  10 ,  110  supported by the intermediate element  60 , in a given angular position on the pantoscopic adjustment axis Y relative to the viewing portion  2 , the intermediate element  60  additionally comprises a notched section  68  cooperating with a notched section  8  arranged in the viewing portion  2 , at the back of the housing  4 . 
     Changing from one angular adjustment position on the pantoscopic axis Y to another is facilitated due to the fact that the notched section  68  is on a flexible portion  70  formed as part of the main portion  72  but thinner, such that the notched section is elastically movable radially to the pantoscopic adjustment axis Y and relative to said main portion  72 . 
     The notched section  8  of the viewing portion  2  extends between a first extreme tooth  8   a  and a second extreme tooth  8   b  and comprises two teeth more than the notched section  68  of the intermediate element  60 . 
     Thus when the pantoscopic element  60  is in a middle adjustment position, illustrated in  FIG. 5 , the notched section  68  engages with all the teeth of the notched section  8 , except for the two extreme teeth  8   a ,  8   b.    
     When the intermediate element  60  is pivoted in a first direction  74  on the pantoscopic adjustment axis Y, the notched section  68  is moved by one tooth relative to the notched section  8 , so that it then engages with the extreme tooth  8   a  of the notched section  8 , as illustrated in  FIG. 6 . The main portion  72  of the intermediate element  60  then abuts a lower wall  4   a  of the housing  4 , at a distance from said first extreme tooth  8   a , which limits the rotation of the intermediate element  60  relative to the viewing portion  2 , about the pantoscopic adjustment axis Y, in the first direction  74 . 
     Conversely, when the intermediate element  60  is pivoted from the middle adjustment position illustrated in  FIG. 5 , in a second direction  76  opposite the first direction  74  and about the pantoscopic adjustment axis Y, the notched section  68  moves by one tooth relative to the notched section  8  and engages with the extreme tooth  8   b  of the notched section  8 , as illustrated in  FIG. 7 . The main portion  72  of the intermediate element  60  then abuts an upper wall  4   b  of the housing  4 , at a distance from said first extreme tooth  8   b , which limits the rotation of the intermediate element  60  relative to the viewing portion  2 , in the second direction  74  about the pantoscopic adjustment axis Y. 
     Advantageously, the angular offset a between two consecutive teeth of the notched sections  8 ,  68 , of the viewing portion  2  and the intermediate element  60  is respectively between 3 degrees and 7 degrees and is preferably substantially equal to 5 degrees. 
     Lastly, it will be noted that the housing  4  has an opening  6  comprising a frontal portion  6   a  extending substantially perpendicularly to the longitudinal direction X, and a side portion  6   b ,  106   b  extending substantially perpendicularly to the direction of the pantoscopic adjustment axis Y, the frontal portion  6   a  and the side portion  6   b  being adjacent. 
     The side portions  6   b ,  106   b  are facing one another, in other words they are facing the face of the user. In addition, each of the side portions  6   b ,  106   b  extends next to the slot  66  and corresponds to it in order to receive the tongue  11 , without significant play in the direction of the folding axis Z when the side arm  10 ,  110  is folded. 
     In addition, the side arm  10 ,  110  and the viewing portion  2  each present a respective front surface  10   a ,  2   a ;  110   a ,  102   a  having a circular form centered on the pantoscopic adjustment axis Y, arranged close to and adjacent to one another when the side arm  10 ,  110  is in the unfolded position. Thus the frontal portion  6   a  of the opening  6  is hidden by the side arm  10 ,  110  when said arm is in the unfolded position, as illustrated in particular in  FIGS. 5 to 7 . 
     In addition, the intermediate element  60  is still received in its entirety within the housing  4 , and does not extend beyond the opening  6  and is even recessed within said opening  6 . As a result, the intermediate element  60  is almost invisible. 
     Of course, the invention is in no way limited to the embodiment just described as a non-limiting example. Thus, although it is not preferred, the housing  4  and the notched section  8  could be arranged in the front portion  12 ,  112  of the side arm  10 ,  110 , and the tongue  11  could be integrally attached to the viewing portion  2 . The intermediate element  60  would then be reversed back to front. 
     In addition, although this is not preferred, in an independent or combined manner the arms  62 ,  64  and the tongue  11  could be reversed, such that the tongue  11  is integrally attached to the intermediate element  60  and the arms  62 ,  64  are integrally attached to the front portion  12 ,  112  of the side arm  10 ,  110 .