Patent Document

FIELD OF THE INVENTION 
       [0001]    The present invention relates to the field of sachets or bags provided with complementary profiled closure shapes or tracks, actuated by a slider. 
         [0002]    It relates more precisely to a slider for actuating profiled closure shapes or tracks for a closure assembly equipping a sachet or bag. 
       BACKGROUND OF THE INVENTION 
       [0003]    Numerous sachets with complementary profiled closure shapes equipped with sliders have already been proposed. 
         [0004]    The attached  FIGS. 1A and 1B  illustrate an example of a slider  1  in accordance with the prior art. 
         [0005]      FIG. 1A  is an end view of a slider of the prior art while  FIG. 1B  is a sectional view of the same slider along line B-B. 
         [0006]    In these  FIGS. 1A and 1B , the profiled shapes or tracks with which the slider is supposed to cooperate have been illustrated and bear the reference P 1  and P 2 , whereas the sachet with which these profiled shapes are associated is referenced S. The sachet or bag S comprise two main sheets S 1  and S 2  bearing respectively one of the two tracks P 1  or P 2 . 
         [0007]    Such a slider  1  is made of moulded plastic material and has a generally known structure. 
         [0008]    More precisely, this slider has a cross-section in an inverse “U” shape, and comprises a base  10  to which are connected two lateral and parallel wings  11  and  12  known as “flanks”. The longitudinal axis of the slider corresponds to its direction of movement when it is installed on a sachet with complementary profiled shapes. The flanks  11  and  12  extend parallel to this axis. 
         [0009]    As is well known per se, the internal space of the slider encloses means  13  adapted for stressing the complementary profiled closure shapes P 1  and P 2  of the sachet, by moving towards or moving away according to the direction of displacement of the slider along these profiled shapes. The expression “internal space” means the space delimited by the base  10  and the flanks  11  and  12 . 
         [0010]    As illustrated on  FIG. 1B , such means  13  comprises generally a central rib  13 C between two lateral channels or corridors  13 A and  13 B receiving respectively a part of one of the two tracks P 1  and P 2 . The channels  13 A and  13 B are not parallel. The channels  13 A and  13 B are convergent towards an axial end AE 1  of the slider and are divergent towards the opposite axial end AE 2 . 
         [0011]    When the slider is moved with the first axial end AE 1  forwards, the complementary tracks P 1  and P 2  are stressed away and the bag is put in an open position, while when the slider is moved with the second axial end AE 2  forwards, the complementary tracks P 1  and P 2  are stressed towards and the bag is put in a closed latch position. 
         [0012]    Such a slider must be placed on a sachet S whereof the two main sheets S 1  and S 2  are provided with complementary profiled closure shapes P 1  and P 2 . 
         [0013]    The technique generally utilised to achieve this consists overall in deforming the slider so as to momentarily move its flanks  11  and  12  away from one another (arrow f of  FIG. 1A ), moving the profiled shapes closer to “cinch” the latter and trap the protuberances T 1  and T 2  with which they are provided, then return the flanks to their initial position (arrows g of  FIG. 1A ). 
         [0014]    This displacement of the flanks is implemented for example by introducing tools “inside” the slider, applying them against the inner faces of the flanks and moving them away mutually. 
         [0015]    In practice, the pivoting movement of the flanks does not operate by flexion of the material of the slider in the attachment zone of the flanks  11 ,  12  to the base  10 . In fact, this zone is too thick and rigid to constitute a preferred folding zone. 
         [0016]    In this case, deformation is completed in predetermined regions of the base. More precisely generally deformation of the slider for opening the slider is operated by pivoting the flanks  11 ,  12  of the slider along respective pivoting lines Pi 1  and Pi 2  corresponding respectively to the median plane of the non parallel channels  13 A and  13 B. As a consequence the pivoting lines Pi 1  and Pi 2  are not parallel and when opening the slider the flanks  11  and  12  do not remain parallel. Consequently the first axial end AE 1  of the slider is less opened than the second axial end AE 2 . This difference of opening between the two ends of the slider leads to some difficulties in placing the slider upon the complementary tracks P 1  and P 2 . 
         [0017]    Document EP-A-0 479 661 discloses such a slider with convergent channels or corridors. 
         [0018]    Also, U.S. Pat. No. 6,584,666 describes a slider provided with load pins. 
         [0019]    Prior art documents U.S. Pat. No. 6,611,996 and U.S. Pat. No. 6,419,391 disclose other embodiments of slider in accordance with the prior art. 
       SUMMARY OF THE INVENTION 
       [0020]    The aim of the present invention is to further improve sliders of the prior art so as to produce satisfactory deformation with a level of acceptable mechanical stress, without risk of breaking. 
         [0021]    Another aim of the invention is to provide a new slider allowing easier insertion upon complementary tracks. 
         [0022]    The present invention accordingly relates to a slider for actuating profiled closure shapes or tracks, especially for a closure assembly equipping a sachet or bag, comprising a base, two flanks parallel to a median central longitudinal plane, and means adapted for stressing respectively said profiled closure shapes or tracks, by moving towards or moving away according to the direction of displacement of the slider along profiled shapes or tracks, for moving the profiled shapes between a closed latch position and an open separated position, and comprising a longitudinal rib which subdivides its internal space into two non parallel corridors or channels. 
         [0023]    This slider is characterized in that a first axial end of the channels wherein the channels are convergent making input end of the channels while a second axial end of the channels wherein the channels are divergent making output end of the channels, the external edge of the input end of the channels is at a distance of the median central longitudinal plane at least equal to the distance separating the internal edge of the output end of the channels from the median central longitudinal plane and the wall of the base in regard of the channels corresponds to the lower thickness of the slider. 
         [0024]    As explained below with the above feature, the present invention warrants that the two flanks are pivoted along parallel axes and consequently that the flanks remain parallel when opening the slider. Consequently inserting the slider upon the complementary tracks is easier than with the slider in accordance with the prior art. 
         [0025]    According to other advantageous and non-limiting characteristics:
       the slider of the invention comprises central rib which is prolonged by a base which overflows on either side of said rib to constitute guide facets of said profiled shapes or tracks;   said base overflows on either side of said rib to constitute guide facets of a protuberance associated with said profiled shapes;   along the longitudinal free edge of each flank extends a stiffening bar, of a thickness greater than that of said flank;   said bar has the same longitudinal range as said flank; and   it comprises projecting load pins on said flanks, in the vicinity of the end of those opposite said base, for opening it provisionally and enabling its engagement on said profiled shapes when stress is exerted on said pins.       
 
         [0031]    The invention relates also to a bag including such a slider. 
         [0032]    Other characteristics and advantages of the invention will emerge from the following detailed description of a preferred embodiment. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0033]    This description will be given in reference to the attached figures, in which: 
           [0034]      FIG. 2  is a perspective view of a slider according to the invention, presented in reversed position; 
           [0035]      FIG. 3  is an end view of the slider of  FIG. 2 ; 
           [0036]      FIG. 4  is a bottom view of the slider of  FIG. 2 ; 
           [0037]      FIG. 5  is an end view of the slider of  FIG. 2 , according to a direction opposite that of  FIG. 3 ; 
           [0038]      FIGS. 6 and 7  are views equivalent to those in  FIGS. 4 and 5 , the flanks being illustrated in a spread position; 
           [0039]      FIG. 8  is a view equivalent to  FIG. 2 , the flanks being illustrated in a spread position; 
           [0040]      FIG. 9  is a view similar to  FIG. 3 , the flanks being illustrated in a spread position; 
           [0041]      FIG. 10  is a view of the slider according to the invention, in perspective 
           [0042]      FIG. 11  illustrates a sectional view of the slider according to the invention in a sectional plane along line XI-XI illustrated on  FIG. 3 . 
           [0043]      FIG. 12  illustrates schematically this sectional view of the slider according to the invention in an illustration similar to  FIG. 1B . 
       
    
    
     DETAILED DESCRIPTION 
       [0044]    The example of slider of the invention overall has a structure known per se, close to that of  FIG. 1 . 
         [0045]    As with this known slider, the slider according to the invention has a cross-section in an inverse “U” shape, with a base  10  to which are attached two lateral and parallel wings (or flanks)  11  and  12 . 
         [0046]    In  FIG. 2 , it is presented in a position opposite to the one it occupies when it is in place on a sachet. 
         [0047]    The internal space of the slider encloses means adapted for stressing complementary profiled closure shapes or tracks of a sachet (marked respectively P 1 , P 2  and S in  FIG. 1 ), by moving towards or moving away according to the direction of displacement of the slider along these profiled shapes or tracks P 1  and P 2 . The expression “internal space” means the space delimited by the base  10  and the flanks  11  and  12 . 
         [0048]    In this case, these means comprise a longitudinal central rib  13 C which extends according to the longitudinal median plane PM of the slider. 
         [0049]    This rib  13 C, originating from material with the inner face of the base  10 , separates the internal space into two channels or corridors C 1  and C 2 . 
         [0050]    As shown more particularly in  FIGS. 3 and 5 , the rib  13 C extends downwards via an elongated central base  14  which overflows on either side of the rib  13 C to constitute guide facets of a protuberance T 1 , T 2  (see  FIG. 1 ), here in the form of a point of an arrow, situated above an associated profiled closure shape P 1 , P 2  at the end of the sheets S 1  and S 2  of the bag. Each facet is turned to the base  10 . “Protuberance” denotes any means associated with the corresponding profiled shape, which allows the slider to cooperate with the sachet. 
         [0051]    This base  14  comprises a first “wide” part  140 , in the general form of an iron base (that is, overall triangular when viewed from above), which is prolonged by a narrower part  141 . 
         [0052]    Also, opposite the two parts  140  and  141  of the base  14 , the inner faces of the flanks  11  and  12  each bear a projection  112 ,  122 , respectively  113 ,  123 , which is also provided with a guide facet of a protuberance. 
         [0053]    The corridors or channels C 1  and C 2  are therefore delimited by the base  10 , the rib  13 C, and its associated base  14 , the inner faces of the flanks  11  and  12  and their associated projections  112 ,  122 ,  113 , and  123 . In other terms, the corridors or channels C 1  and C 2  have the form of throats or grooves with convergent edges. 
         [0054]    In the example shown here, along the longitudinal free rim of each flank  11  and  12  extends a stiffening bar  110 , respectively  120 , of a thickness greater than the remaining part of the flank. 
         [0055]    In the example shown here, each bar  110  and  120  has on its free face, opposite the base  10 , a keying finger  111 , respectively  121 . 
         [0056]    In an embodiment which is not shown here, the slider could have the general structure described in French application published under No. 2 924 312, in which load pins are provided in the extension of the flanks  11  and  12 . 
         [0057]    In the figures, it is evident that the opposite ends of the slider conform to arches  15 , of a thickness greater than the rest of its body. 
         [0058]    In accordance with the invention, the abovementioned corridors C 1  and C 2  define channels which are convergent towards an axial end AE 1  of the slider and are divergent towards the opposite axial end AE 2 . 
         [0059]    In other words said channels C 1  and C 2  extend generally according to respective median rectilinear planes Y 1 -Y′ 1  and Y 2 -Y′ 2  which are not parallel. 
         [0060]    A first axial end C 11 , C 21  of the channels C 1  and C 2  wherein the channels are convergent makes input end of the channels. This input end of the channels corresponds to the free opening defined between the central rib  13 C and the respective projections  113 ,  123 . 
         [0061]    A second axial end C 12 , C 22  of the channels C 1  and C 2  wherein the channels are divergent makes output end of the channels. This output end of the channels corresponds to the free opening defined between the central rib  13 C and the respective projections  112 ,  122 . 
         [0062]    Moreover as indicated above and as illustrated on  FIGS. 11 and 12 , the slider of the invention is characterized in that, the external edge EC 11 , EC 21  of the input end of the channels C 1  and C 2  is at a distance l 2  of the median central longitudinal plane PM at least equal to the distance l 1  separating the internal edge IC 12 , IC 22  of the output end of the channels C 1  and C 2  from the median central longitudinal plane PM and the wall of the base  10  in regard of the channels C 1  and C 2  corresponds to the lower thickness of the slider. 
         [0063]    As illustrated on  FIG. 12 , the external edge EC 11 , EC 21  of the input end of the channels C 1  and C 2  corresponds to the face of the projections  113 ,  123  directed towards the median plane PM, while the internal edge IC 12 , IC 22  of the output end of the channels C 1  and C 2  corresponds to the face of the central rib  13 C directed towards the projections  112 ,  122 . 
         [0064]    As explained above with the above feature, the present invention warrants that the two flanks  11  and  12  are pivoted along parallel axes X-X′, which represent preferred fold lines. 
         [0065]    Consequently the flanks  11  and  12  remain parallel when opening the slider. Consequently inserting the slider upon the complementary tracks P 1  and P 2  is easier than with a slider in accordance with the prior art. 
         [0066]    Preferentially the external edge EC 11 , EC 21  of the input end of the channels C 1  and C 2  is at a distance l 2  of the median central longitudinal plane PM slightly greater than the distance l 1  separating the internal edge IC 12 , IC 22  of the output end of the channels C 1  and C 2  from the median central longitudinal plane PM and the wall of the base  10  in regard of the channels C 1  and C 2  corresponds to the lower thickness of the slider. 
         [0067]    In practice, these corridors or channels C 1  and C 2  are bordered laterally by the base of the rib  13 C and by the foot of the projections  112 ,  122 ,  113 , and  123 . 
         [0068]    In an attempt to deform the slider according to the invention, in order to place profiled shapes or tracks such as those P 1  and P 2  of  FIG. 1 , the flanks  11  and  12  are moved apart from one another, for example by exerting a force on their inner face, as shown by arrows f of  FIG. 8 . This allows the corridors or channels C 1  and C 2  to be “opened” and enables placing of the profiled shapes or tracks P 1  and P 2 . 
         [0069]    Once this operation is done, the force is stopped and the flanks  11  and  12  naturally regain their initial position. 
         [0070]    This force is applied most closely to the free end of the flanks  11 ,  12  to produce the biggest possible lever arm. 
         [0071]    Of course, the slider “folds” in the zones where there is least material. These “fold zones” correspond to the regions of the base  10  deprived of material outgrowth. 
         [0072]    These zones correspond to the corridors or channels C 1  and C 2  along axis X-X′. 
         [0073]    The letter P in  FIG. 7  is used to mark the deformation planes of the base  10  of the slider, along axes X-X′. 
         [0074]    With respect to parallel planes, the mechanical stresses to be implemented to produce these deformations are reasonable and the risks of breaking the slider are reduced. 
         [0075]    Of course, the slider of the invention can be provided differently to that described here. It can especially be devoid of stiffening bars. 
         [0076]    In a variant embodiment, not shown, the above axes X-X′ could be marked visually, for example in the form of a line traced on the inner face of the base  10 , or even in the form of a groove made therein.

Technology Category: 4