Patent Publication Number: US-10314397-B2

Title: Device and method for fixing a push element

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is the National Stage of PCT/EP2016/059888 filed on May 3, 2016, which claims priority under 35 U.S.C. § 119 of German Application No. 10 2015 106 856.7 filed on May 4, 2015, the disclosures of which are incorporated by reference. The international application under PCT article 21(2) was not published in English. 
     BACKGROUND OF THE INVENTION 
     The present invention relates to a device for fixing a push element, in particular a drawer, to a rail of a pull-out guide, said device comprising a clamping mechanism with a receptacle into which a web-shaped holding part can be inserted, wherein a self-locking clamping lever is provided on the receptacle, by means of which the holding part is secured in a frictionally engaged manner against being pulled out, and a method for fixing a push element. 
     EP 1 285 604 discloses a device for fixing a drawer to a rail of a pull-out guide, in which a base part which can be fastened to the drawer and a latching element which can be fixed to the pull-out guide are provided. In order to compensate for the distance between the guide rails of the pull-out guides, the latching element can be displaced within specific tolerances relative to the base part. The holding forces are limited by the design of the latching element and the base part as a plastic part, especially in the case of heavy drawers which extend in the pull-out direction up to the maximum pull-out position. In addition, it is desirable to position the drawer as precisely as possible within the furniture body in order to obtain an attractive joint pattern. 
     WO 2009/149479 discloses a device for releasably coupling a drawer to a pull-out guide, in which a holding part and a counter-holding part are connected to one another via a resilient material piece. This leads to a reduction in the positional accuracy in the longitudinal direction. In the lateral direction, the drawer is fixed to the rail by means of a latching device. In the case of the standard stop tests for drawers, in which the drawers are pulled out with load, however, comparatively low holding forces of such a latching connection are obtained. 
     SUMMARY OF THE INVENTION 
     It is therefore the object of the present invention to provide a device and a method for fixing a push element in which high holding forces can be provided. 
     This object is achieved by a device and a method according to the invention as described below. 
     The device according to the invention for fixing a push element comprises a clamping mechanism with a receptacle, into which a web-shaped holding part can be inserted, wherein a self-locking clamping lever is provided on the receptacle by means of which the holding part is secured in a frictionally engaged manner against pulling out. As a result, a particularly stable securing of the push element can take place by means of the self-locking clamping lever, in particular also with regard to stop tests, in which the drawer is moved into the maximum opening position in the loaded state. The self-locking clamping lever of the clamping mechanism ensures that the holding part is held in such a way that it cannot be pulled out further from the receptacle in the opening direction. However, insertion of the holding part into the receptacle of the clamping mechanism is comparatively simple since only small frictional forces have to be overcome so that assembly can be designed in a simple manner. In addition, a frictionally engaged connection of the clamping lever can be used to effect a stepless fixing of the holding part, which allows particularly precise positioning of the push element in the opening direction. 
     A frictionally engaged or force-locked connection according to the invention differs from a form-fitting connection in that the holding forces are provided by frictional forces and not by form-fitting abutment elements, such as teeth or stops. In this way, a continuous adjustment can be achieved in the case of a frictionally engaged fixing of the holding part, which is independent of stop elements. 
     For the frictionally engaged connection, the web-shaped holding part can have a substantially planar surface, which in certain areas is in contact with a contact surface on the clamping lever. The holding part can be strip-shaped, angled, U-shaped, produced as a hollow profile or with other geometries, in particular made of metal, wherein a section of a profile can be used for the frictionally engaged connection. The holding part can also be formed by a section of the pull-out guide profile. 
     Preferably, the clamping lever is rotatably mounted about a pivot. In this case, the clamping lever can be pretensioned into a locked position, in particular via one or more springs or via an energy storage device. 
     According to a preferred embodiment of the invention, means for unlocking the clamping lever are provided, by means of which the force-locked connection of the clamping lever can be released from the holding part. A linearly movable slide or button can be provided for unlocking the clamping lever. In this case, the clamping lever can be designed as a two-armed lever, wherein a first arm rests with a contact surface against the holding part, and a second arm can be moved over the means for unlocking the clamping lever. By adjusting the length of the lever arms, appropriate force transmission ratios can be achieved, wherein the contact surface must be moved only slightly away from the holding part in order to unlock the clamping lever. 
     Preferably, the clamping lever rests on the holding part via a linear contact surface, which extends parallel to the pivot of the clamping lever. The contact surface can be edge-shaped, rounded or designed with a different contact surface to provide high clamping forces. In this clamping system, the high clamping forces are generated by a multiplication of forces by the lever effect. 
     The clamping mechanism can preferably be secured in a stepless manner to the holding part, so that the drawer is placed on the pull-out guide during assembly and is pushed in slightly, and as soon as the clamping mechanism is fixed to the holding part, the fitter is given the certainty that the drawer is unable to slip inadvertently when it is pulled out of the extension guide in the opening direction. Rather, the clamping mechanism is activated as soon as the holding part is guided past the clamping lever in the receptacle. Subsequent further insertion of the drawer for stepless adjustment is thus easily possible. 
     For a particularly stable fastening of the drawer, the holding part and the contact surface of the clamping lever resting on the holding part can be made of metal, for example of a steel sheet. In contrast to metal, plastic flows, so that only small forces can be absorbed via the clamping mechanism, wherein the use of plastic materials, in particular reinforced plastics, is certainly possible. 
     Preferably, the pivot of the clamping lever is arranged in the insertion direction in front of a contact surface of the clamping lever on the holding part. As a result, self-locking is effected, wherein, in the mounted position, an angle between the contact surface of the clamping lever with respect to the pivot can be arranged at an angle to the longitudinal direction of the holding part between 55° and 89°, in particular 70° to 85°. Due to the angular position of the clamping lever, the freewheeling direction and the locking direction are defined in the clamping system. When the holding part is loaded in the blocking direction, a self-reinforcing effect occurs, so that the clamping force also increases with rising loading of the holding part in the blocking direction. 
     For easy assembly, the receptacle may be formed on a fastening part on which the clamping lever is rotatably mounted. Then the clamping lever can be pre-mounted with the receptacle as a unit on the rail or the drawer. Preferably, the fastening part is displaceably mounted on or in a housing. As a result, the fastening part can be moved relative to the housing via means for lateral adjustment, so that an exact alignment of the drawer is also possible in the horizontal direction perpendicular to the movement direction of the pull-out guide. A height adjustment and/or a depth adjustment can also be provided. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be explained below in closer detail with reference to an exemplary embodiment with reference to the attached drawings, wherein: 
         FIG. 1  shows a perspective view of a piece of furniture with a drawer; 
         FIG. 2  shows a bottom view of the drawer of  FIG. 1 ; 
         FIG. 3  shows a perspective detailed view of the device according to the invention for fixing the drawer; 
         FIG. 4  shows a perspective view of the device of  FIG. 3  in the mounted position; 
         FIG. 5  shows a perspective view of the device without a drawer before assembly; 
         FIG. 6  shows a perspective view of the device without housing during assembly; 
         FIGS. 7 to 9  show several views of the device for fixing a drawer without holding part; 
         FIG. 10  shows a view of a modified device for fixing a drawer without lateral adjustment; 
         FIG. 11  shows an exploded perspective view of a modified device without holding part, and 
         FIGS. 12A to 12C  show several views of the device of  FIG. 11 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A piece of furniture  1  comprises a furniture body  2 , on the side walls of which one or more pull-out guides  3  are fixed, each of which has at least one movable rail  5 . A drawer  4  is held displaceably on two such rails  5 , wherein a device  10  or  10 ′ is provided on each rail  5  for fixing the drawer  4  to the rail  5 , as can be seen from the bottom view of  FIG. 2 . On a bottom  7  of the drawer  4 , a first device  10  with lateral adjustment for fixing the drawer  4  is fixed to a rail  5  and a second device  10 ′ without lateral adjustment for fixing the drawer to a rail  5 . Each device  10  and  10 ′ comprises a housing  15 , which is fixed to a front panel  6  and/or to the bottom  7  of the drawer  4 . 
     In the detailed view of  FIG. 3 , the device  10  is shown during assembly. The housing  15  can be fixed to the underside of the drawer  4  via fastening means  16 , wherein a receptacle  20  is provided for inserting a holding part  12 . The holding part  12  is attached to the rail  5  of the pull-out guide  3 . In this case, the web-shaped holding part  12  can optionally be fixed to the rail  5  via an integrally formed tab  9 , e.g. by welding, or can be fixed to the rail  5  via further components, or the holding part  12  is a part of the rail profile of the rail  5 . A device  11  for depth adjustment is provided on the tab  9 , which has a rotationally fixed threaded bolt  14  on which a knurled nut  13  is rotatably supported but non-displaceable in the axial direction. As a result, by rotating the knurled nut  13 , the threaded bolt  14  can be moved in the longitudinal direction of the rail  5  and thus move a stop which predetermines the insertion depth of the holding part  12  in the receptacle  20 . Optionally, such a device  11  for depth adjustment can also be dispensed with. 
     For assembly, the drawer  4  is placed on the two rails  5  of the two pull-out guides  3  and pushed into the closed position. In this case, a respective web-shaped holding part  12  is inserted at opposite sides into the receptacle  20  of the device  10  or  10 ′ and fixed via a clamping mechanism that secures the holding part  12  in a clamping and frictionally engaged manner against pulling out. 
       FIG. 4  shows the mounted position of the drawer  4 . The holding part  12  has been inserted into the receptacle  20  and secured there against pulling out. The lateral joint pattern can now be adapted via a device  18  for lateral adjustment. The device  18  for lateral adjustment comprises a knurled nut  19  which, by rotating, causes the housing  15  to move laterally in the horizontal direction relative to the receptacle  20  to perform lateral adjustment. 
       FIG. 5  shows the device  10  without the holding part  12 . The device  10  comprises a slide  17  or button, which is used for unlocking the clamping mechanism. As a result, the drawer  4  can be dismantled again after the assembly by actuating the slide  17 . 
       FIG. 6  shows the device  10  without the housing  15 , but with the holding part  12 , which is clamped in the receptacle  20  in a clamping manner. 
     The clamping mechanism comprises a clamping lever  25 , which is rotatably mounted on a fastening part  23  about a pivot  24 . The fastening part  23  is of plate-shaped design and forms a side wall  22  of the receptacle  20 , which is arranged opposite the clamping lever  25 . The holding part  12  is fixed in a clamping and frictionally engaged manner between a contact surface  26  of the clamping lever  25  and the side wall  22  and secured against being pulled out. For this purpose, the pivot  24  is arranged in front of the contact surface  26  in the direction of insertion of the holding part  12  so that the holding part  12 , during insertion into the receptacle  20 , first passes a plane perpendicular to the insertion direction in which the pivot  24  is arranged before the holding part  12  touches the contact surface  26 . The clamping lever  25  is thus designed to be self-locking and, in the case of tensile forces on the holding part  12 , the clamping lever  25  with the contact surface  26  is pressed even more strongly against the holding part  12 . 
     The clamping lever  25  is designed as a two-armed lever, wherein the contact surface  26  is formed on one arm for the clamping fixing of the holding part  12 , and means for unlocking the clamping lever  25  act on a second arm  27 . The clamping lever  25  is designed in the form of an angle and is pretensioned into the clamping position by means of an integrally formed spring  30 . In this case, the spring  30  is designed as a leaf spring and is supported on the housing  15 . The means for unlocking comprise a bolt  28  which is slidably formed in a wedge-shaped gap  29  between the arm  27  and the fastening part  23 . When the bolt  28  is displaced towards the end of the arm  27 , the arm  27  is moved by the wedge-shaped design of the gap  29 , and the clamping lever  25  rotates such that the contact surface  26  comes out of engagement with the holding part  12 . As a result, the holding part  12  can be easily pulled out after the clamping lever  25  has been turned. The bolt  28  is guided along a side wall of the fastening part  23 . 
     The clamping lever  25  is made in this case from a bent metal plate which engages around a section of the plate-shaped fastening part  23  in a U-shaped manner. The bottom of the U is thereby formed on the contact surface  26 , so that a line-shaped contact surface  26  rests against the holding part. 
       FIG. 7  shows an exploded view of the device  10  with the housing  15 . A slot-shaped receptacle  33  is provided on the housing  15 , on which the fastening part  23  is held displaceably with the clamping lever  25 . A head section on the pivot  24  is guided in a groove-shaped guide  34 . The fastening part  23  can be guided in the housing  15  via further or other surfaces. Furthermore, the slide  17  is shown, which is designed as a cap-shaped part and holds the bolt  28  between two arms  31 . The bolt  28  can be displaced along the wedge-shaped gap  29  by a movement of the slide  17  along the fastening part  23 . The slide  17  is thereby pretensioned by a spring  32  into an initial position, in which the bolt  28  does not unlock the clamping lever  25 . Unlocking of the clamping lever  25  is effected only by shifting the slide  17  against the force of the spring  32 . 
     Furthermore, the device  18  for lateral adjustment is shown, in which a threaded bolt  40  engages a threaded bore  41 . A knurled nut  19  is fixed on the threaded bolt  40 , wherein one edge of the knurled nut engages in a U-shaped receptacle  35  on the fastening part  23 . By rotating the knurled nut  19 , the fastening part  23  can thus be displaced relative to the housing  15  in the longitudinal direction of the threaded bolt  40 , i.e. in a plane parallel to the front panel  6  of the drawer  4 . 
     In  FIGS. 8A to 8C , the device  10  with the housing  15  is shown in detail. The plate-shaped fastening part  23  is slidably mounted within the receptacle  33  of the housing  15  and in turn itself supports the clamping lever  25  via the pivot  24 . The slide  17  engages around the housing  15  in a U-shaped manner and is linearly guided in order to pivot the clamping lever  25  for an unlocking process by displacement. 
     In  FIG. 9 , the device  10  is shown in an unlocking position, in which the slide  17  has been pushed onto the housing  15 . The pin  28  thus moves the clamping lever  25  so that the contact surface  26  moves slightly away from the opposing side wall  22  so that a holding part  12 , which is arranged between the side wall  22  and the contact surface  26 , can be pulled out of the receptacle  20 . The movement of the contact surface  26  can be in a range between 0.02 to 4 mm, in particular 0.4 mm to 2 mm. 
       FIG. 10  shows the device  10 ′, which is designed like the device  10 , but without the device  18  for lateral adjustment. In this respect, the knurled nut  19  and the threaded bolt  40  are missing. Apart from that, the device  10 ′ can be designed in a structurally identical or mirror-symmetrical manner to the device  10 . The fastening part  23  can be movably mounted in the housing  15 , so that the device  10 ′ forms a floating bearing, whereas on the opposite side a fixed bearing is provided which positions the drawer  4  within the furniture body  2  in the horizontal lateral direction. 
       FIG. 11  shows a modified device  10 ″, by means of which a web-shaped holding part  12  shown in  FIG. 2  can be secured in a clamping manner. The device  10 ″ comprises a housing  15 ′ on which an outer plate  50  and an inner plate  52  are arranged. The plates  50  and  52  are provided with a slit-shaped receptacle  20 , in which a side wall  22  is arranged on one side, and a clamping lever  25  is rotatably mounted on the opposite side about a pivot  24 . As a result, the web-shaped holding part  12  can be displaced in a force-locked manner between a contact surface  26  on the clamping lever  25  and the side wall  22 . On the plates  50  and  52 , elongated holes  53  are further formed, which serve to guide a bolt  56  which is connected to the slide  51 . In this case, the slide  51  is pretensioned into a starting position by a spring  54 , wherein the spring  54  is fixed on the slide  51  on the one hand and with the pin  55  on the plate  50  on the other hand. 
     The clamping lever  25  comprises an actuating arm  57 , which can cooperates with the slide  51 . 
     A receptacle  31  for inserting a spring  30  is also provided on the plate-shaped mounting part  23 ′, which spring is designed as a leaf spring and acts on the clamping lever  25  to pretension the latter into the locked position. 
     In  FIGS. 12A to 12C , the device  10 ″ is shown in the mounted position. The slide  51  can be moved along the elongated holes  53  against the force of the spring  54 , wherein the slide then acts on the arm  57  of the clamping lever in order to rotate it clockwise, so that a holding part  12 , which is fixed in a force-locked manner between the side wall  22  and the contact  26 , can be unlocked. Other means for unlocking the clamping lever  25  can also be provided. 
     In the exemplary embodiment shown, both the clamping lever  25  and the fastening part  23  consist of metal, in particular of a steel sheet. As a result, particularly high holding forces can be applied to the likewise metallic holding part  12 . 
     LIST OF REFERENCE NUMERALS 
     
         
           1  A piece of furniture 
           2  Furniture body 
           3  Pull-out guide 
           4  Drawer 
           5  Rail 
           6  Front panel 
           7  Bottom 
           8  Tab 
           10 ,  10 ′ Device 
           11  Device 
           12  Holding part 
           13  Knurled nut 
           14  Threaded bolt 
           15  Housing 
           16  Fastening means 
           17  Slide 
           18  Device 
           19  Knurled nut 
           20  Receptacle 
           22  Side wall 
           23  Fastening part 
           24  Pivot 
           25  Clamping lever 
           26  Contact surface 
           27  Arm 
           28  Bolt 
           39  Gap 
           30  Spring 
           31  Arm 
           32  Spring 
           33  Receptacle 
           34  Guide 
           35  Receptacle 
           40  Threaded bolt 
           41  Threaded bore 
           50  Plate 
           51  Slide 
           52  Plate 
           53  Elongated hole 
           54  Spring 
           57  Actuating arm