Abstract:
A jaw member ( 11 ) for a support assembly ( 10 ) for securing a bicycle ( 1 ) to a load carrier ( 2 ) for a vehicle ( 8 ), The jaw member ( 13, 14 ) comprises a frame work structure formed by at least one support element and at least one rib ( 31, 32, 35, 36 ), The frame work structure is specifically adapted to enable the jaw member to withstand a relative high amount of tensile stress while still being relatively light weight.

Description:
TECHNICAL FIELD 
       [0001]    A clamping jaw for a support assembly for a bicycle carrier for a vehicle, a knob for transferring torque to the clamping jaw of the support assembly and a support assembly comprising the clamping jaw and the knob. 
       BACKGROUND 
       [0002]    Load carriers for vehicles are widely used to provide the vehicles, such as automobiles, with an increased loading capacity. A load carrier is usually mounted on the vehicles tow hook, an equivalent position at the rear of the vehicle, or on roof racks. Wherever the load carrier is mounted, there is a need to readily secure the bicycle to the load carrier especially before transportation of the bicycle in traffic environments. A bicycle which is accidentally detached from the load carrier during transportation could cause severe damage 
         [0003]    Support assemblies for securing a bicycle to a load carrier for a vehicle are widely used together with load carriers for bicycles. It is common that support assemblies use a clamping jaw to secure the bicycle to the support assembly. One such support assembly is disclosed in the International patent application no. WO 2005/065817 Thule Sweden AB. The clamping jaw of the support assembly comprises a first and a second jaw member which upon tightening with a tightening device, such as a rotating knob, are pressed together about a portion of a bicycle, usually the frame of the bicycle, to secure the bicycle to the load carrier. It is the mouth ribs, i.e. side edges, of the jaw members which engage the bicycle to retain the bicycle to the load carrier, 
         [0004]    A clamping jaw of a support assembly can be manufactured in a wide variety of different ways. It has become more common lately to manufacture the clamping jaw from a plastic material e.g. by form molding the two jaw members for example. To provide structural integrity to a jaw member, the jaw member in the WO 2009/065817 document is formed by a frame work structure in terms of that the jaw member comprises a plurality of ribs which project from the outer housing and towards the interior of the jaw member and supportive ribs extending between the side edges of the jaw member. The inside of the “mouth” of the clamping jaw thus has a plurality of exposed ribs. A grip section can be formed at the center section of the jaw member by filling the cavities, or grooves, formed by the frame work structure with a soft thermoplastic polymer. It requires a large amount of thermoplastic polymers to fill the void formed by the frame work structure to provide a reasonable grip section which further adds weight to the clamping jaw. 
         [0005]    There is a need for the clamping jaws of the support assemblies and its individual components to withstand a high amount of crash violence. Crash violence is a term for describing the forces imparted to the components during an accident with the vehicle, such as a crash or a collision scenario with another vehicle. During a crash or a collision, the vehicle, the bicycle carrier and of course the support assembly retaining the bicycle to the bicycle carrier is subjected to an extreme amount of crash violence. It has been found that clamping jaws of support assemblies can accidentally break during such high levels of stress, especially when mounted to larger bicycles. In order to overcome this problem clamping jaws are made stronger by increasing the thickness of the material of the clamping jaw. This however makes the clamping jaws bigger and clumsier and more difficult to mount to bicycles as these sometimes tend to have a limited amount of space available for the clamping jaw. 
         [0006]    It has been found that during a crash or a collision scenario, at least one of the jaw members of the clamping jaw of a support assembly is especially vulnerable when subjected to high tensile stress. The tensile stress is generally as highest in the mouth of the clamping jaw, i.e. on the bicycle facing side. With reference to a cross section of the jaw member at the center of the mouth, the tensile stress is gradually decreasing closer to the centre of gravity of the cross section and will transcend to a compression stress towards the distal end of the structure. 
         [0007]    It has now been found that clamping jaws of the aforementioned kind have some disadvantages. If a clamping jaw having a frame work structure needs to be very rigid they tend to become very large and very heavy, and thus not very user friendly nor easy to mount to ta bicycle. 
         [0008]    The support assembly disclosed in the WO 2009/065817 document comprises a rotateable knob connected to an axle to impart the first and the second jaw members of the clamping jaw with a force to press the jaws together. The axle extends to an opposing end of the support assembly comprising an annular clamp which counteracts the rotating motion of the knob to press the first and the second jaw member together. 
         [0009]    There is however always a risk of the user imparts the knob with a too high torque and thus accidentally damages the bicycle. Some support assemblies are thus provided with a torque limiting mechanism to limit the amount of transferrable torque to the clamping jaw via the knob. One such support assembly is disclosed in the European patent application no. EP 2,230,412 A1. 
         [0010]    To prevent or significantly reduce the risk of theft of bicycles, support assemblies for load carriers can be provided with locks. The support assembly disclosed in the European patent application no. EP 2,230,412 A1 also comprises a lock mechanism which is cooperating with the torque limiting mechanism to lock or unlock the support assembly. The solution disclosed in the latter document is however associated with a number of drawbacks, The lock mechanism is quite complex due to the configuration of the torque limiting mechanism, 
       SUMMARY 
       [0011]    It is an object of the present disclosure to solve at least one of the aforementioned drawbacks, or to provide for a useful alternative. The object is at least partly met by a jaw member for a support assembly for securing a bicycle to a load carrier for vehicles. The jaw member comprises a frame work structure formed by at least one support element and at least one rib. The support element of the jaw member comprises a bicycle facing side adapted to be positioned adjacent, or substantially adjacent, the bicycle when mounted thereto, and a distal side. The rib extends from the distal side of the support element of the jaw member. 
         [0012]    The frame work structure of the jaw member has at least one rib which extends from the distal side of the support element provides for a jaw member which is rigid, i.e. has a high structural integrity and can resist relatively high load of tensile stress, while still being relatively light weighted. It provides a clamping jaw with improved resistance against tensile stress while still having a relatively low weight. In this aspect, the ribs mentioned herein are strengthening ribs. A strengthening rib can have a width/height ratio of at least ⅕, i.e. it is at least five times higher than its thickness, and preferably a length which is at least as long as its height, preferably at least twice as long as the height, more preferably five times the height. 
         [0013]    A clamping jaw comprising a first and a second jaw member, the first and/or the second jaw member can have said frame work structure, i.e. the second jaw member can also comprise the frame work structure. The second jaw member can be pivotally attached to the first jaw member, or in the proximity thereof, at a pivot axis to form a clamping jaw. 
         [0014]    The rib can extend from the distal side of the support element in a direction substantially perpendicular to the support element. The jaw member becomes extra rigid if the rib extends substantially perpendicular, or perpendicular, out from the distal side of the support element, even if the support element itself has an arc form. 
         [0015]    According to an aspect, the frame work structure is positioned at a centre section of the jaw member. Having the frame work at the centre of the jaw member, independently if it is the first or the second, the jaw member is provided with a substantially planar bicycle facing side surface at the centre, i.e. in the mouth. This enables the bicycle facing side to be coated, or provided with a second material, different from which the jaw member or the frame work structure is manufactured from. For example, the frame work structure of the jaw member can be form moulded using a first thermo plastic polymer e.g. polypropylene, and the bicycle facing side of the jaw member can be coated, or provided, with a second thermoplastic polymer such as a softer polyethylene. The support element provides fro a flat smooth surface to be coated, which requires little amount of coating material. Hence the bicycle facing side can be provided with a relative soft material, or a friction enhancing material easy and at low cost. The frame work structure can comprise a friction enhancing material defining a grip section. 
         [0016]    According to an aspect the first and/or the second jaw member can comprise a first and a second mouth rib. The frame work structure is positioned between the first and the second mouth ribs. Optionally the mouth ribs are separated by a groove on either side of the frame work structure but can be formed integrally therewith. The grooves provide added strength by providing additional ribs to the jaw member. 
         [0017]    According to an aspect, the frame work structure comprises two or more ribs, preferably three or more ribs. The two or more ribs are advantageously positioned on either side of a longitudinal centreline of the jaw member and extend along the longitudinal centreline, preferably parallel with the longitudinal centre line. 
         [0018]    At least one additional supportive rib can be positioned between two ribs. The at least one supportive rib interconnects the two ribs, or the two or more ribs, and provide additional strength to the jaw member while adding very little weight to the jaw member. A more complex frame work structure is achieved. Instead of having longitudinal groves between the ribs, the jaw member tends to get square like grooves, or triangular formed grooves dependent of the angle between the ribs, and the supportive ribs. 
         [0019]    According to an aspect the at least one rib has a base having a width proximal to the support element, and a rim distal to the support element, wherein the width is gradually decreasing towards the rim. The cross section of the rib thus has a slightly tapered form. It has been found that this is important as the weight can be reduced while the structural integrity is still kept high. There are two positive effects, not only is the structural integrity of the jaw member improved but the ribs are also easier to manufactured when form moulding a jaw member using two opposing form moulding tools. 
         [0020]    According to an aspect, the support element and the at least one rib are formed in one unitary piece of material, preferably by form moulding. 
         [0021]    The jaw member can comprise a second frame work structure at the pivot axis, and the a first frame work structure at the mouth of the clamping jaw. The first frame work structure is as mentioned above, while the second frame work structure can have the ribs projecting from the bicycle facing side of the support element, i.e. the ribs of the support elements projects into the mouth, i.e. from the bicycle facing side of the jaw member and not from the distal side of the support element. This could be advantageous for the configuration of the tensioning device of a support assembly. 
         [0022]    According to an aspect, the clamping jaw comprises a first and a second opposing jaw member adapted to be clamped together about a portion of a bicycle, wherein the first jaw member comprises a frame work structure comprising a support element and at least on rib projecting from the support element. The rib of the support element projects from the support element in a direction away from the second jaw member. Optionally the second jaw member comprises a frame work structure comprising a support element and at least on rib projecting from the support element The rib of the support element projects from the support element in a direction away from the first jaw member. 
         [0023]    According to a second aspect, it is an object of the present disclosure to solve at least one of the aforementioned drawbacks, or to provide for a useful alternative. The object is at least partly met by a knob for transferring a torque to an object, such as a support assembly for a bicycle carrier. The knob has a torque limiting mechanism and a lock. The lock can be operated between a locked position in which the knob in unable to transfer torque to the object, and an unlocked position in which the knob is able to transfer torque to the object. The torque limiting mechanism comprises a first and a second gear member, the first gear member is biased into working cooperation with the second gear member wherein upon a torque threshold value, the first and second gear members are disengaged from the working cooperation so that a torque limiting mechanism is provided. The knob has a longitudinal centre axis about which the knob is adapted to rotate to transfer the torque. The first gear member is biased towards the second gear member in a direction along the longitudinal centre axis of the knob into the working cooperation. 
         [0024]    The knob provides for a compact knob which is tamper resistant via a lock and still has a good torque limiting mechanism using few components. 
         [0025]    According to an aspect, the lock engages the first and/or second gear member directly when being in the unlocked position. 
         [0026]    According to an aspect, the lock comprises a lock cylinder; the lock cylinder engages the first and/or the second gear member directly when the lock cylinder is in the unlocked position. 
         [0027]    According to an aspect, the first gear member comprises gear teeth adapted to engage the second gear member. The second gear member can comprise corresponding gear teeth. The second gear member can further as an option, comprise lock teeth to engage the lock. The lock teeth advantageously extend around the periphery of the second gear member forming a plurality of positions in which the lock, and especially the lock cylinder, can engage the second gear member directly. Instead of a lock cylinder, which generally tends to work by rotating about its own longitudinal axis, a displaceable lock pin or the like can be used. 
         [0028]    According to an aspect, the gear teeth of the first and/or the corresponding gear teeth of the second gear member extends in a direction along the longitudinal centre axis of the knob. As the biasing direction of the first gear member is biased along the longitudinal centre line of the knob, it is very advantageous that the respective gear teeth extend along the longitudinal centre line. They thus have their contact surfaces intersecting with the longitudinal centre line should they be extrapolated. 
         [0029]    According to an aspect, the lock teeth of the second gear member extend in a radial direction with respect to the longitudinal centre axis of the knob. 
         [0030]    According to an aspect, the present invention relates two a bicycle carrier comprising at least one support assembly comprising at least one clamping jaw and at least one knob for tightening the clamping jaw as disclosed herein. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0031]    Non-limiting embodiments of the present invention will be described in greater detail with reference to the accompanying figures in which; 
           [0032]      FIG. 1  shows a bicycle mounted on a bicycle carrier on a vehicle and retained by a support assembly having a clamping jaw according to an embodiment of the present invention; 
           [0033]      FIG. 2  shows the clamping jaw of  FIG. 1  with a view in perspective and in greater detail; 
           [0034]      FIG. 3  shows the clamping jaw of  FIG. 1  with a view towards the side; 
           [0035]      FIG. 4  shows an exploded view of the clamping jaw of  FIG. 1 ; 
           [0036]      FIG. 5  shows the first jaw member of the clamping jaw of  FIG. 1 ; 
           [0037]      FIG. 6  shows a cross section of the first jaw member of  FIG. 5 ; 
           [0038]      FIG. 7  shows a cross section of the second jaw member of  FIG. 1 ; 
           [0039]      FIG. 8  shows a schematic cross section of the cross section shown in  FIG. 6 ; 
           [0040]      FIG. 9 a -9 c    shows schematic cross sections of different jaw members; 
           [0041]      FIG. 10  shows the knob of the support assembly of  FIG. 1 ; 
           [0042]      FIG. 11 a -11 b    shows an exploded view of the knob of  FIG. 10  in different perspective views and; 
           [0043]      FIG. 12  shows a cross section of the knob shown in  FIG. 10 . 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0044]      FIG. 1  shows a bicycle  1  having a frame  3  mounted on a bicycle carrier  2  on a vehicle  6 . A support assembly  10  retains the bicycle  1  to the bicycle carrier  2  and assists in preventing the bicycle from accidentally detach from the bicycle carrier  2 . The bicycle carrier  2  can be provided with one or more support assemblies  10 , preferably two or more. 
         [0045]    The support assembly  10  comprises a clamping jaw  11  clamping about the frame  3  of the bicycle  2 . A tightening device  12  in the form of a rotateable knob  50  is used to tighten or untighten the clamping jaw  11  from the frame  3  of the bicycle  2 . 
         [0046]      FIG. 2  shows the clamping jaw  11  in greater detail. The clamping jaw  11  comprises a first and a second jaw member  13 ,  14  which in the shown embodiment are pivotably arranged to each other about a pivot axis P. Each jaw member  13 ,  14  comprise a proximal end  13   p,    14   p,  and a distal end  13   d,    14   d,  with respect to the pivot axis P. The rotateable knob  50  (not shown in  FIG. 2 ) has a working position WP between the pivot axis P and the distal ends of the first and the second jaw member  13 ,  14 . When the rotateable knob  50  is rotated the jaw members  13 ,  14  are pivotally displaced together, i.e. pressed together, or pivotally displaced from each other to release the frame  3  of the bicycle  2 . 
         [0047]      FIG. 3  shows the clamping jaw  11  as seen from the side. The first and the second jaw members  13 ,  14  comprise a support element  19  (not shown) having a bicycle faring side  20 , which also can be referred to as a frame facing side, facing towards the frame  3  of the bicycle  2 , and a distal side  21  facing away front the frame  3  and the bicycle  2 . The frame  3  is indicated with dashed lines in  FIG. 3 . The bicycle facing sides  20  of the support elements  19  of the first and the second jaw members  13 ,  14  define a mouth  22  having a gap  23 . The gap  23  is formed by the distal ends  13   d,    14   d,  of the first and the second jaw member  13 ,  14 . As is noticeable, the bicycle facing sides  20  of the first and the second jaw members  13 ,  14  have an arc shaped form forming a mouth having a substantially oval form when seen from the side as shown in  FIG. 3 . The oval form of the mouth  22  permits the clamping jaw  11  to readily grasp around the frame  3  of the bicycle  2  and retain the same after the first and the second jaw members  13 ,  14  are pressed together. 
         [0048]      FIG. 4  shows an exploded view of the clamping jaw  11  of  FIG. 2 .  FIG. 4  shows the first and the second jaw members  13 ,  14 , a biasing member  15  in the form of a spring  16 . A bolt  17  connects the first and the second jaw members  13 ,  14  and extends through the spring  16 . The spring  16  biases the first and the second jaw members  13 ,  14 , away from each other, so that when the knob  50  is rotated to untighten the clamping jaw  11 , the first and the second jaw members  13 ,  14  are biased away from each other. 
         [0049]      FIG. 5  shows a perspective view of the first jaw member  13  in greater detail and with a view towards the upper side of the first jaw member  13 , referred to as the distal side  21  of the support element  10  of the first jaw member  13 .  FIG. 5  further shows the proximal end  13   p  and the distal end  13   d  of the jaw member  13 , and the pivot axis P. An aperture  17  extends through the first jaw member  13  and permits an axle (not shown) of the tightening device  12  to extend through the first jaw member  13  as will be explained below in greater detail. Such mentioned axle would be connected to the knob  50  in the present case. A longitudinal centerline CJ extends along the first jaw member  13 . 
         [0050]    A first and a second rib  31 ,  32  extend along the longitudinal centerline CJ. The purpose of these ribs  31 ,  32  will be explained with reference to  FIG. 6 . 
         [0051]      FIG. 6  is a cross section of  FIG. 3  along the lines I-I.  FIG. 6  shows a cross section of the first jaw member  13 , the support element  19  having the bicycle facing side  20  and the distal side  21 , the mouth  22 , and the first and the second ribs  31 ,  32 . For the purpose of orientation, the longitudinal centerline CJ and a vertical axis V divides the first jaw member into a left and a right section. 
         [0052]    The bicycle facing side  20  of the support element  19  has a planar surface and a first and a second rib  31 ,  32  which extends form the distal side  21  of the support element  19  of the first jaw member  13 . The first jaw member  13  thus comprises a center section CS which extends along the longitudinal centerline CJ and with respect to the cross section, has an extension perpendicular to the longitudinal centerline CJ. The center section CS if formed by a portion of the first jaw member  13 , in this case the support element  19 . The bicycle facing side  20  of the support element  19  has as mentioned above a slightly arc shaped form along the longitudinal center line, but a smooth planar surface, in contrast to the distal side  21  of the support element  19  of the first jaw member  13  which has the first and the second rib  31 ,  32  extending from the distal side  21 . It is of course possible that the bicycle facing side can have a flat planar surface, a slightly concave or convex surface, nevertheless it has no protruding ribs from the bicycle facing side, in contrast to the distal side of the support element  19 . 
         [0053]    This makes the bicycle facing side  20  of the support element  19  suitable for being provided with a second material, such as a friction enhancing material. With the planar surface of the support element forming the bicycle facing side, low amounts of friction enhancing material can be used. 
         [0054]    The cross section of the first jaw member  13  when viewed as shown in  FIG. 6  could be described as having raised walls extending from the distal end  21  of the support element  19  extending in a direction away from the bicycle facing side  20  of the support element  19 . A third and a forth rib  35 ,  36  form a first and a second side rib  35 ,  36 . The ribs  31 ,  32 ,  35 ,  36  together define three grooves  45  formed between the ribs  31 ,  32 ,  35 ,  36 . Having grooves  45  reduces the overall weight of the first jaw member  13 . The first and the second side ribs  35 ,  36  diverges back towards the bicycle facing side  20  and defines a first and a second mouth rib  37 ,  38  of the mouth  22  of the first jaw member  13 . A groove  39  separates the first and the second side rib  35 ,  36  from the first and the second mouth rib  37 ,  38   
         [0055]    The cross section of the first and the second ribs  31 ,  32  have a thicker base as compared to the thickness at the top. In  FIG. 6 , the thickness of the base is indicated as TB and the thickness at the top, just before the top transcends to a smooth apex, is indicated with TT. The ribs  31 ,  32  are thus tapered in their cross section. At least one jaw member having at least one rib, preferably one rib arranged on either side of the centerline, having a tapering cross section, has been found to be very advantageous. 
         [0056]    As mentioned, the first and the second ribs  31 ,  32  extend substantially parallel with the longitudinal centerline CJ. As is also noticeable, the distal side  21  of the support element  19  is not covered, e.g. by a lid or similar. The upper side of the first jaw member  13  thus has grooves or channels, which reduces the overall weight of the first jaw member  13  while still providing a good structural strength to the first jaw member  13 . 
         [0057]      FIG. 7  shows the cross section of the second jaw member  14  along the line II-II as seen in  FIG. 2 . The frame work structure of the second jaw member  14  will be described in greater detail below. As is noticed in  FIG. 7 , the second jaw member  14  has a support element  19  having a bicycle facing side  20 . The second jaw member  14  further comprises a center section CS which extends along the longitudinal centerline CJ. The support element  19 ′ has a planar surface at the center section CS, and a first and a second rib  33 ,  34  which extends from the distal side  21  of the support element  19 . The bicycle facing side  20  of the support element  19  has as mentioned above an arc shaped form, but a smooth planar surface, in contrast to the distal side  21  of the of the support  10  element  19 ′ which comprises the first and the second rib  33 ,  34  extending from the distal side  21  and away from the bicycle facing side  20  of the support element  19 . 
         [0058]    A third and a forth rib  35 ,  36  form a first and a second side rib  35 ,  36  extending substantially parallel with the first and the second ribs  33 ,  34 . The first and the second side ribs  35 ,  36  diverges back towards the bicycle facing side  20  and define a first and a second side mouth rib  37 ,  38  of the mouth  22  of the second jaw member  14 . A groove  39  separates the first and the second side rib  35 ,  36  from the first and the second mouth rib  37 ,  38 . 
         [0059]    The second jaw member  14  also has support ribs  38  extending between the ribs  33 ,  34 ,  35 ,  36  interconnecting the ribs  33 ,  34 ,  35 ,  36  to further improve the structural integrity of the second jaw member  14 . The support ribs  38  have the same height as the first and the second rib  33 ,  34 . The support ribs  38  form a plurality of square like grooves  45 ′ together with the ribs  33 ,  34 ,  35 ,  36 . Having longitudinal grooves  45 ′ reduces the overall weight of the second jaw member  14  while still providing a relatively high structural strength to the second jaw member  14 . 
         [0060]    The first and the second jaw member  13 ,  14  will be described in further with reference to  FIG. 8 , which shows a schematic cross section of the second jaw member  14  shown in  FIG. 7 . It should be noted however that the cross section of the second jaw member  14  is in principle the same as the cross section of the first jaw member  13 , shown in  FIG. 6 . 
         [0061]      FIG. 8  shows the jaw member  14  having a support element  19 ′ comprising a continuous planar center section CS having a bicycle facing side  20  and a distal side  21 . The support element  19 ′ comprises four ribs  33 ,  34 ,  35 ,  36  extending from the distal side  21  of the support element  19 ′ and substantially perpendicular from the support element  19 . A first and a second rib  33 ,  34  is positioned on either side of the longitudinal centerline CJ, a first and second side rib  35 ,  36  is positioned on either side of the first and the second rib  33 ,  34  forming three grooves  45 ′ between the ribs  33 ,  34 ,  35 ,  36 . The first and the second side ribs  35 ,  36  diverges back towards the bicycle facing side  20  of the support element  19 ′ forming the first and the second side mouth rib  37 ,  38 . 
         [0062]    Having a continuous planar bicycle facing side  20  on the support element  19 , and especially in the center section CS, will make the second jaw member  14  more resistant against tensile stress as the second jaw member  14  will have plenty of material withstanding the tensile stress at the bicycle facing side  20 . The centre of gravity of the cross section, as seen in  FIGS. 8-9   c  is relatively close towards the bicycle facing side  20  of the support element  19 ′ which further indicates that the transition from tensile stress to compression stress is closer to the support element and thus the bicycle facing side  20 , it would also indicate that the tensile stress is lower than the compression stress, which is very positive with respect to the structural strength of the second jaw member  14 . The same reasoning applies to the first jaw member  13  of course. 
         [0063]    As can be seen in  FIG. 8 , the bicycle facing side  20  of the support element  19 ′, in this case on the second jaw member  14 , comprises a grip section  40 . The grip section is positioned on the center section CS of the second jaw member  14  and is formed by a relatively soft thermoplastic material such as polyethylene or a mixture of polyethylene and polypropylene. The purpose of the grip section  40  is to improve the grip between the clamping jaw and the frame of the bicycle. 
         [0064]    The grip is improved by providing an improved friction between the frame of the bicycle and the clamping jaw, and by providing an increased grip area. As used herein, the term grip area is intended to mean the actual surface area which is in contact with the frame of the bicycle after the clamping jaw has been mounted to the bicycle and tightened in an appropriate manner permitting transportation of the bicycle on public roads and in a normal traffic situation. 
         [0065]    As is also noticeable is that the first and the second side mouth ribs  37 ,  38  comprises grip sections  41 ,  42   
         [0066]    With reference to  FIGS. 9 a   - 9   c,  different schematic center sections will be briefly described.  FIG. 9 a    shows a cross section of a jaw member having a support element  19  with a bicycle facing side  20  and a distal side  21 . A first and a second side rib  35 ,  36  extending substantially perpendicularly from the distal side  21  of the support element  19  and which diverges back towards the bicycle facing side  20  of the support element  19  forming a first and a second side mouth rib  37 ,  38 . 
         [0067]    The jaw member of  FIG. 9 b    has only a first and a second side rib  35 ,  36  which extends substantially perpendicular from the distal side  21  of the support element  19  of the jaw member. The jaw member of  FIG. 9 b    does not have any side mouth ribs, the form and extension of the support element  19  thus defines the sides of the mouth of the clamping jaw. The jaw member of  FIG. 9 c    is similar to the jaw member of  FIG. 9 b    with the difference that it comprises an additional rib  33  extending from distal side  21  of the support element  19  and which is centrally positioned between the first and the second side ribs  35 ,  36 . 
         [0068]    The bicycle facing side  20  is as mentioned planar. According to an aspect, the bicycle facing side  20 , at least in the central section CS, has a continuous planar surface area of about at least 2 cm 2 , preferably at least 3 cm 2 , more preferably 4-20 cm 2 . A continuous planar surface area on the bicycle facing side will not only permit the formation of a grip section  40 , but also improve the structural properties of the jaw member. The planar surface can be flat, concave or convex, while still being planar. 
         [0069]    As mentioned above with reference to the first and the second jaw member  13 ,  14 , the grooves  45  can be longitudinal channel like grooves if the ribs are not interconnected with support ribs. If support ribs are present, the grooves  45 ,  45 ′ can be square like grooves or triangular formed grooves for example. Mixtures of grooves having different forms are of course possible. 
         [0070]    The distinct configuration of the first jaw member  13 , and the second jaw member  14  is configured similarly or identical, provides a clamping jaw  11  which has a low weight and a high structural integrity, i.e. strength. As mentioned, it has been found that clamping jaws of support assemblies for bicycle carriers are known to break when being exposed to too high tensile stress, i.e. due to a low tolerance against tensile stress. The clamping jaw described herein has a low weight while still being resistant to a relatively high tensile stress subjected to the jaw member at the bicycle facing side of the support element. 
         [0071]    The first jaw member  13  and optionally the second jaw member  14  are form moulded using a two component technique and using a hard plastic material and a softer plastic material. The first and the second jaw members  13 ,  14  can be similarly formed and configured but it is also possible that the first jaw member is different from the second jaw member, the first jaw member could be form moulded and the second jaw member could be formed by stainless steel for example. In the shown embodiment in  FIG. 4 , both the first and the second jaw members  13 ,  14  are manufactured using a form molding technique. 
         [0072]      FIG. 10  shows the tightening device  12  in the form of the rotateable knob  50  in greater detail. The knob  50  is used to press the first and the second jaw members together (not shown in  FIG. 10 ). When the knob  50  is rotated, or turned, the first and the second jaw members are either pressed together or displaced from each other upon which a clamping force will be reduced. The knob  50  is provided with a lock  51 , in this case a lock cylinder  51  adapted to receive a key (not shown) for operating the lock cylinder  52 . The lock  51  is configured to either prevent the knob  50  from being able to displace the first and the second jaw members from each other or to permit the first and the second jaw members to be pressed against each other, in a manner which will be described in greater detail herein. 
         [0073]    The individual components of the knob  50  will be described in greater detail with reference to  FIGS. 11 a -11 b    simultaneously.  FIGS. 11 a -11 b    show the knob  50  having a longitudinal center axis C in exploded view and with a perspective view. From the left,  FIGS. 11 a -11 b    show a first and a second housing screw  53 ,  54 , a housing  55 , an axle receiving member  56 , an interior housing  57 , a spring  58 , a first gear member  59 , a second gear member  60 , a lock washer  61 , a lid  62  and the lock cylinder  52  having a lock bolt  52   a,  in this case a rotateable lock bolt. 
         [0074]    An axle, such as a screw or bolt cooperating with the opposite end of the support assembly is connected to the axle receiving member to form the tightening device  12 . Such connection and function is known per se and will not be described further herein. 
         [0075]    The knob  50  comprises a torque limiting mechanism  70 , the torque limiting mechanism  70  is adapted to prevent a user from imparting too much torque to the axle receiving member  53 , and thus from pressing the first and the second jaw members (not shown) together too hard. 
         [0076]    The torque limiting mechanism  70  is operating through the interaction between the first and the second gear members  59 ,  60  as will be described herein. As can be noted, the first gear member  59  comprises gear teeth  59  extending along the longitudinal center axis C and having an angled surface  59 ″ on each of the gear teeth  59 . The first gear member  59  is adapted to be in working cooperation with the second gear member  60 . The second gear member  60  also comprises gear teeth  60 ′ extending along the longitudinal center axis C and having an angled surface  60 ″ on each of the gear teeth  60 . The gear teeth  59 ′ of the first gear member  59  are adapted to interact with the gear teeth  60 ′ of the second gear member  60  so as to transfer torque imparted by a user there between, however, as a threshold level of torque is reached the gear teeth  59 ,  60 ′ will start to slip and eventually loose grip with each other. As the grip between the first and the second gear member  59 ′,  60  is lost the first gear member  59  will rotate with respect to the second gear member  60  and thus prevent the rotating motion imparted by the user from being transferred between the first and the second gear members  59 ,  60 . 
         [0077]    A biasing member, in the form the spring  58 , in this case a helical spring, biases the first and the second gear members  59 ,  60  together. The spring  58  is configured to bias the first gear member  59  in a direction along the longitudinal center axis C towards the second gear member in into working cooperation with the second gear member  60 . 
         [0078]    The spring  58  and the first gear member  59  are positioned inside of the interior housing  57 . The interior housing  57  comprises an aperture  57   a  through which the axle receiving member  56  extends. The axle receiving member  56  and the interior housing  57  are further prevented from rotation with respect to each other via a polygonal connection  56   b,    57   b,  in  30  this case a hexagonal connection on the axle receiving member  56  and the interior housing  57 . The first gear member  59  can be displaced inside of the interior housing  57  and while being guided along tracks  57   c  on the interior surface of the interior housing  57 . The tracks  57   c  of the interior housing  57  prevents the first gear member  59  from rotation with respect to the interior housing  57  while permitting the first gear member  59  to be displaced along the longitudinal center line C of the knob  50 . Corresponding guiding tracks  59  are arranged on the first gear member  59 . 
         [0079]    The second gear member  60  comprises an aperture through which the axle receiving member  56  extends. The lock washer  61  is positioned around the axle receiving member  56  at the end thereof to connect the second gear member  60  to the axle receiving member  56 . 
         [0080]    The lock cylinder  52 , which is accessible from the outside of the lid  62 , is configured to cooperate directly with the second gear member  60 . The lock mechanism of the knob  50  is thus configured to operate directly on one of the gear members  59 ,  60 , in this case the second gear member  60 , to provide for the locking function. 
         [0081]    As is noticeable, the second gear member  60  comprises lock teeth  60   a  which extends in a direction substantially perpendicular to the longitudinal center axis C and are thus adapted to operate in a radial direction thereof. The lock teeth  60   a  has a form which is adapted to cooperate with a lock bolt  52   a  of the lock cylinder  52 . 
         [0082]    The housing  55  and the lid  62  can rotate freely with respect to the axle receiving member  56 , the interior housing  57 , the first gear member  59  and the second gear member  60  when the lock cylinder  52  is not engaging the second gear member  60 . The knob  50  is thus tamper proof and cannot be used to press first and the second jaw members together. When the lock bolt  52   a  is rotated into engagement with the lock teeth  60   a  of the second gear member  60 , the lid  62  and the housing  55  are engaged with the torque limiting mechanism  70  and thus can be used to tighten or releasing the first and the second jaw members. A simple and useful theft protection function is incorporated into the knob  50  which uses relatively few components. 
         [0083]      FIG. 12  shows a cross section of the knob  50  with the longitudinal center axis C.  FIG. 12  shows the housing  55  connected to the lid  62  via the first and the second housing screws  53 ,  54  (not shown in  FIG. 12 ). The axle receiving member  56 , enveloped by the interior housing  57 . The spring  58  is threaded onto the axle receiving member  56  and biasing the first gear member  59  into engagement with the second gear member  60 . The lock cylinder  52  is directly engaging the second gear member  60  while being accessible from the outside via the lid  62 . 
         [0084]    In general terms, the clamping jaw can comprise a first and a second opposing jaw member adapted to be clamped together about a portion of a bicycle, wherein the first jaw member comprises a frame work structure comprising a support element and at least on rib projecting from the support element. The rib of the support element projects from the support element in a direction away from the second jaw member. Optionally the second jaw member comprises a frame work structure comprising a support element and at least on rib projecting from the support element. The rib of the support element projects from the support element in a direction away from the first jaw member. 
         [0085]    The support element provides the jaw members(s) and the clamping jaw with a planar, or flat, surface towards the bicycle while the supporting ribs project away from the planar, or flat, bicycle facing surface.