Abstract:
A tolerance compensating assembly of automatically compensating tolerances in the spacing between two structural members comprises a mounting bolt  10 , a base element  4 , an adjustment sleeve  6  and a driver  8 . The base element  4  and the adjustment sleeve  6  form a first thread pairing G 1  of a predetermined spiral direction for adjusting the adjustment sleeve  6  relative to the base element  4 . The base element  4  and the mounting bolt  10  form a second thread pairing G 2  in the opposite spiral direction for clamping the two structural members B 1 , B 2 . The driver  8  is a separate structural member and disengageably connected to the adjustment sleeve  6  and has a plurality of flexibly resilient clamping portions  34  spaced along its periphery, which provide for frictional contact with the thread of the mounting bolt  10  above a predetermined torsional force.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates to a tolerance compensating assembly for automatically compensating tolerances in the spacing between two pre-mounted structural members or structural members to be mounted which are to be clamped together.  
         [0002]     A great number of such tolerance compensating assemblies are known, see for example EP 0 176 663 B1, DE 42 24 575 C2, DE 101 51 383 A1, DE-GM 201 190012 and DE-GM 203 14 003. They serve in compensating the tolerance between pre-mounted structural members which ensues in manufacturing and/or mounting. To this end, these tolerance compensating assemblies normally comprise an adjustment sleeve having a so-called drive portion which can enter into frictional contact connection with a mounting bolt. Upon rotating the mounting bolt, the adjustment sleeve is therefore also rotated until it is fixedly supported against one of the structural members to be clamped, whereupon given further rotation of the mounting bolt and the corresponding increase in torsional force, the frictional contact connection is overcome such that both structural members can be clamped together in the adjustment sleeve by the mounting bolt.  
         [0003]     The tolerance compensating assemblies known from the prior art normally consist either wholly or partly of metal elements, wherein the non-metallic elements are made of e.g. a thermoplastic synthetic. These known tolerance compensating assemblies are relatively expensive and those which make use of thermoplastic synthetics have the disadvantage of the clamping between the two structural members diminishing due to the relaxation of the plastic.  
       SUMMARY OF THE INVENTION  
       [0004]     It is the object of the present invention to provide a tolerance compensating assembly for automatically compensating tolerances in the spacing between two pre-mounted structural members which are to be clamped together which can be manufactured economically and of a configuration suitable for manufacturing from plastic.  
         [0005]     This object is solved by the tolerance compensating assembly defined in claim  1 .  
         [0006]     In addition to a base element and an adjustment sleeve, the tolerance compensating assembly configured according to the invention also comprises a driver configured as a separate structural member and disengageably connected to the adjustment sleeve. Said driver exhibits a plurality of flexibly resilient clamping portions spaced along its periphery which form a disengageable frictional contact connection with the thread of the mounting bolt above a given torsional force.  
         [0007]     Since the driver, which performs the frictional drag function necessary for compensating tolerance, is a separate structural member, manufacturing the individual components of the tolerance compensating assembly is relatively simple. The invention furthermore enables a “complete plastic solution” in which both the base element and the adjustment sleeve as well as the driver are made of plastic.  
         [0008]     In particular, the invention offers the possibility of manufacturing the base element and the adjustment sleeve from a low-relaxation plastic such as e.g. a duromer plastic. Since these materials have a relaxation of almost zero, the two structural members remain securely clamped even after lengthy use and even under high pressures. However, a different type of plastic could in principle also be used such as e.g. a thermoplastic material.  
         [0009]     The driver is preferably made of a flexibly resilient plastic such as e.g. a thermoplastic synthetic, in order to enter into frictional contact connection with the thread of the mounting bolt and thus be able to perform the frictional drag function.  
         [0010]     The base element, the adjustment sleeve and the driver preferably form a pre-mountable structural unit which can be stored, transported and otherwise handled as such.  
         [0011]     Further developments and modifications of the invention are defined in the sub-claims. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]     The drawings will be used to describe an exemplary embodiment of the invention in greater detail. Shown is:  
         [0013]      FIG. 1  is a perspective view of a structural unit of a tolerance compensating assembly configured according to the invention in the pre-mounted state;  
         [0014]      FIG. 2  is a perspective exploded view of the structural unit from  FIG. 1 ;  
         [0015]      FIG. 3  is a longitudinal section through the structural unit of  FIG. 1  in the visual direction of the III-III arrow in  FIG. 4 ;  
         [0016]      FIG. 4  is a plan view of the structural unit of  FIGS. 1 and 3 ;  
         [0017]      FIG. 5  is a side view of the structural unit from the preceding figures;  
         [0018]      FIG. 6  is a sectional view in the visual direction of the VI-VI arrow in  FIG. 5 ;  
         [0019]      FIG. 7  is an enlarged view of Detail B from  FIG. 6 ;  
         [0020]      FIG. 8  is a sectional view of the tolerance compensating assembly in the visual direction of the VIII-VIII arrow in  FIG. 10  prior to assembly;  
         [0021]      FIG. 9  is a sectional view of the tolerance compensating assembly corresponding to  FIG. 8  after assembly;  
         [0022]      FIG. 10  is a plan view of the tolerance compensating assembly from  FIGS. 8 and 9 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0023]     FIGS.  1  to  7  show a structural unit  2  for a tolerance compensating assembly as depicted in FIGS.  8  to  10 . The structural unit  2 , which forms the tolerance compensating assembly together with a conventional mounting bolt  10  ( FIGS. 8, 9 ), consists of a base element  4 , an adjustment sleeve  6  and a driver  8 , as can especially be seen in  FIG. 2 .  
         [0024]     The base element  4  (see  FIGS. 2 and 3  in particular) consist of a sleeve-shaped body  12  having a throughbore disposed with an internal thread  14  and, adjacent thereto, a drive feature  16  for attachment of a tool (not shown). The drive feature  16  is configured as an internal six-lobe recess head in the exemplary embodiment as shown but may, however, also be of a different configuration.  
         [0025]     The sleeve-shaped body  12  consists of a mounting portion  18  and an adjustment portion  20 , separated by an annular flange  22 . The mounting portion  18  has a thread  19  at its outer periphery in the exemplary embodiment shown and serves to fix the base element  4  to a first structural member B 1  ( FIGS. 8, 9 ), as will be explained in greater detail below.  
         [0026]     The adjustment portion  20  is provided with an adjustment thread  21  at its outer periphery which is engageable with adjustment sleeve  6  as will likewise be explained in greater detail below.  
         [0027]     The adjustment sleeve  6  is essentially configured as a hollow cylindrical body  24  having a flange  26  fitted to an axial end of said hollow cylindrical body  24 . The body  24  exhibits a throughbore disposed with a thread  28 , which forms a first thread pairing G 1  together with adjustment thread  21  of the base element  4  ( FIG. 9 ). The adjustment sleeve  6  is provided with slots  30  through the flange  26 , the shape of which is adapted to the shape of the driver  8  such that it can receive the driver  8 .  
         [0028]     The driver  8  is configured as an annular body  32  having a plurality of clamping projections  34  extending radially inwardly spaced along its inner periphery. Three clamping projections  34  are provided in the exemplary embodiment as shown; however a greater or lesser number of clamping projections is also possible.  
         [0029]     The annular body  32  is furthermore provided with two diametrically opposing, radially outwardly extending brackets  36 , which give way at their outer ends to axial retaining extensions  38  perpendicular thereto. The retaining extensions  38  have a U-shaped profile and are provided with a retention tab  40  on both peripherally opposing sides, as can readily be seen in  FIG. 2 .  
         [0030]     The structural unit  2  comprised of the base element  4 , the adjustment sleeve  6  and the driver  8  is pre-assembled. To this end, the driver  8  is inserted from above into the slot  30  of adjustment sleeve  6 . The shape of the driver  8  and the shape of the slot  30  compliment one another such that the annular body  32  with the brackets  36  is completely received by the adjustment sleeve  6 , enabling the top of the driver  8  to be aligned flush with or slightly set into the face side  27  of the adjustment sleeve  6  (see  FIG. 1 ). The retaining extensions  38  of the bracket  36  have a certain elasticity due to their U-shaped profile such that the retention tabs  40  snap in under the base of the flange  26  upon the driver  8  being inserted into the adjustment sleeve  6 , whereby the driver  8  is disengageably held in the adjustment sleeve  6 .  
         [0031]     The adjustment sleeve  6  together with the driver  8  is now screwed to the adjustment portion  20  of the base element  4 , wherein the thread  28  of the adjustment sleeve  6  and the adjustment thread  21  of the base element  4 , as mentioned above, form the first thread pairing G 1  ( FIGS. 8, 9 ). In the exemplary embodiment as shown, the adjustment thread  21  of the base element is configured as an external threading and the thread  28  of the adjustment sleeve  6  is configured as an internal threading. The base element  4  and the adjustment sleeve  6  could instead also be structurally configured such that the adjustment thread of the base element is an internal threading and the associated thread of the adjustment sleeve  6  is an external threading.  
         [0032]     As can especially be seen in  FIGS. 2, 6  and  7 , the base element  4  and the driver  8  are provided with locking means in the form of nubs  42 ,  44  as a securing device, providing a locking of the adjustment sleeve  6  relative to the base element  4 . More specifically, the base element is provided with three nubs  42  spaced over its periphery, which each can latch engageably between two axially-extending nubs  44  of the driver  8 . Using three nubs  42  spaced over the periphery enables at a thread pitch of 1.5 mm, for example, a retention force of between 0 and maximum 0.5 mm. Using a different number of nubs  42  is, of course, also to be understood.  
         [0033]     As mentioned at the outset, the individual components of the structural unit  2  are all made of plastic. The base element  4  and the adjustment sleeve  6  are advantageously comprised of a hard, low-relaxation plastic, more preferably a duroplastic synthetic such as e.g. PF6771 phenol resin material. Duroplastic materials have the advantage of very low relaxation. Depending upon application, however, a different material such as e.g. a thermoplastic synthetic can also be used.  
         [0034]     The driver  8  is advantageously comprised of a thermoplastic synthetic which lends sufficient elasticity to the clamping projections  34  to exert a frictional drag function. Conceivable here would be, for example, a glass fiber-reinforced polyamide such as e.g. PA6GF50.  
         [0035]     The assembly and operation of the tolerance compensating assembly will now be described with reference to FIGS.  8  to  10 . The tolerance compensating assembly serves to clamp the structural members B 1  and B 2 , depicted in their preassembled state. The structural members B 1  and B 2  have a spacing A which can vary in size due to manufacturing and/or mounting tolerances. An appropriate tolerance compensation must therefore be made when clamping the two structural members B 1  and B 2 .  
         [0036]     The structural unit  2  is first connected to the structural member B 1  by screwing the mounting portion  18  into the structural member B 1 . In the exemplary embodiment shown, the thread  19  of the mounting portion  18  is configured as a known per se self-tapping and/or grooved thread which forms a corresponding counter-thread in a cylindrical bore  46  of the structural member B 1  when the base element  4  is screwed into the structural member B 1  with a tool (not shown) via the drive feature  16 .  
         [0037]     Such a plastic-in-plastic (P-in-P) threaded connection between the base element  4  and the structural member B 1  is conceivable when there is a corresponding consistency differential between the structural member B 1  and the base element  4 . However, instead of this type of P-in-P threaded connection, a different fastening system can also be provided for affixing the base element  4  to the structural member B 1 .  
         [0038]     When the structural unit  2  is fastened to the structural member B 1 , the mounting bolt  10  is inserted from above through the throughbore of the base element  4  until the clamping projections  34  of the driver  8  frictionally contact the thread of the mounting bolt  10 . When the mounting bolt  10  is now rotated, the driver  8  also rotates via the clamping projections  34  and the adjustment sleeve  6  via the driver  8 . In the exemplary embodiment depicted, the thread pairing G 1  between the base element  4  and the adjustment sleeve  6  is configured as a left-handed thread pairing such that the adjustment sleeve  6  is screwed upward as a result of being driven via the mounting bolt  10  (in  FIGS. 8, 9 ) until the adjustment sleeve  6  is fixedly supported against the structural member B 2 . If the mounting bolt  10  is turned further, this increases the torsional force, thereby loosening the frictional contact connection between the mounting bolt  10  and the clamping projections  34  of the driver  8 . The bolt  10  can now be screwed into the base element  4 , wherein the thread of the mounting bolt  10  and the thread  14  of the base element  4  form a second thread pairing G 2 . This thread pairing is right-handed in the exemplary embodiment as shown; i.e. configured opposite to that of thread pairing G 1 , so that now both B 1  and B 2  structural members can be clamped to the structural unit  2  by means of the mounting bolt  10 .  
         [0039]     As indicated above, there is virtually no relaxation to the materials used for the base element  4  and the adjustment sleeve such that the clamping to the two B 1  and B 2  structural members also remains intact over the long term and under high pressures.  
         [0040]     When the mounting bolt  10  is again disengaged, the adjustment sleeve  6  screws back down into its initial position. When spacing A changes (e.g. upon subsequent leveling of joint sealants), spacing A can then be re-bridged.  
         [0041]     In order to be able to easily disengage the adjustment sleeve  6  from the structural element B 2 , the face side  27  of the adjustment sleeve  6  e.g. exhibits a smooth contact surface which is advantageously limited by an annular outer edge to said face side  27 . The rest of the face side is then recessed from this annular contact surface in that it is, for example, configured to be concave.  
         [0042]     It is to be understood that the dimensions (length and diameter) of thread pairings G 1  and G 2  can be varied in order to, depending on use, meet their respective relevant requirements. It is likewise to be understood that thread pairing G 1  can also be configured to be right-handed and thread pairing G 2  can be configured to be left-handed.