Abstract:
The invention relates to a caster, for example, a bed caster, appliance caster, heavy-load caster or the like, which have versatile uses in the private and commercial sectors. The inventive caster has a braking device that acts upon the lateral faces of the wheel.

Description:
DESCRIPTION  
         [0001]    The invention concerns a transport roller, such as is often used for example as a bed roller, an apparatus roller, a heavy-load roller or suchlike in the private and industrial sector. As a rule, the roller is steerable. Such a steering roller is shown in DE 197 24 577.  
           [0002]    The known steering roller has a wheel, which is carried in a rotary manner on a fixture.  
           [0003]    On this fixture there is also arranged a brake shoe, which by means of a bolt on the fixture can be pressed against the running face of the wheel and again released from the running face of the wheel.  
           [0004]    Depending on the material type and/or material hardness of the running face of the wheel, different forces are required to achieve a desired braking effect. The braking power changes with increasing wear on the running face.  
           [0005]    It is intended with the invention to make available a transport roller of the initially mentioned type with an alternative braking device, whereby the braking device should in particular be ready for operation independently of the wear on the wheel and independently of the material of the running face of the wheel.  
           [0006]    In its most general form of embodiment, the invention relates to a transport roller with the following features:  
           [0007]    a wheel, which is carried in a rotary manner on a fixture,  
           [0008]    a one- or multi-piece bearing block, which is fixed to the fixture or is a component of the fixture,  
           [0009]    two sections of the bearing block run outside the wheel in its peripheral area on opposite sides of the wheel,  
           [0010]    each section has a pivot bearing, on which a brake lever is carried,  
           [0011]    the brake levers are connected via a spring at their end running above the pivot bearing in such a way that the spacing of the brake levers at their ends is variable by means of a change in the spring length between the linking points of the spring to the brake levers.  
           [0012]    In this way, a transport roller is made available with a braking device which does not act on the running face of the wheel, but on the side faces of the wheel, in particular a wheel web, i.e. the section of the wheel which runs between the wheel hub and the wheel running face and essentially has the form of a disc with a central hole.  
           [0013]    In this way, the braking device is independent of the type and material of the running face. The braking device is thus also independent of the degree of wear on the running face.  
           [0014]    A further advantage consists in the fact that the braking device acts laterally on the wheel, where less dirt usually accumulates. The dirt is picked up chiefly by the running face and cannot impair the operating ability of the braking device in the case of the transport roller mentioned here.  
           [0015]    A further important aspect of the transport roller is that the associated braking device can also be retrofitted on existing transport rollers.  
           [0016]    This applies in particular when the spring acting upon the brake lever is itself acted upon by a bolt, which is already present for example in the form of embodiment according to DE 197 24 577 C1 and performs various functions inside a steering roller.  
           [0017]    According to one form of embodiment, the bearing block runs essentially parallel to the wheel axis, or in other words: normal to the running direction of the wheel. With a one-part bearing block, it goes without saying that it has to overlap the wheel with a gap. The bearing block can, however, be readily designed in two parts. It is advantageous if sections of the bearing block are present respectively on both sides of the wheel, to which sections the brake levers can be coupled.  
           [0018]    The structural shape then remains small. In principle, the pivot bearings for the brake levers can also lie beside the running face of the wheel. The levers must then, however, be sharply curved. The sections of the bearing block can, as vertical pins, also be a component of the fixture for the wheel.  
           [0019]    In order to achieve as high a degree of variability as possible in respect of the braking power, one form of embodiment makes provision such that the brake levers are designed in such a way that their arms pointing away from the wheel, i.e. as a rule the arms running above the pivot bearing, are shorter than the arms lying opposite. Such a form of embodiment is explained in greater detail in the following description of the figures.  
           [0020]    This also shows that the brake levers can be arranged structurally identically, but mirror-inverted inside the braking device and bent in the direction of one another at their wheel-side (lower) end.  
           [0021]    The “brake path” can thus be reduced, in particular in the case of wheels with relatively wide running faces and only a disc-type wheel web.  
           [0022]    The sections of the brake levers important for braking can be designed with brake linings (friction linings).  
           [0023]    Whilst the pivot bearings for the brake levers can be simple bolts, the spring—depending on the arrangement inside the fixture—can be fitted at its ends on corresponding pins of the brake levers or be fixed in a keyed manner. 
       
    
    
       [0024]    Further features of the invention and the mode of operation of the described braking device emerge from the features of the subclaims as well as the further parts of the application, in particular the following description of the figures.  
         [0025]    A form of embodiment of the invention is represented diagrammatically in various views and details, i.e. in  
         [0026]    [0026]FIG. 1: a perspective view, partially in vertical section, of a transport roller,  
         [0027]    [0027]FIG. 2: a perspective partial view of the wheel solely with the associated braking device,  
         [0028]    [0028]FIG. 3: a perspective separate view of the braking device,  
         [0029]    [0029]FIG. 4: a partial section through the transport roller according to FIG. 1 in the area of its brake lever. 
     
    
       [0030]    [0030]FIG. 1 shows a transport roller with a fixture  10 , in which amongst other things a crown gear  12  is carried, through which a bolt (a toothed spindle)  14  reaches. A shaft  16  is also a component of fixture  10 , on which shaft there sits a bearing which carries a wheel (running wheel)  18  in a rotary manner.  
         [0031]    Wheel  18  has a running face  18   f , on which a brake shoe acts according to the prior art (DE 197 24 577 C1).  
         [0032]    The braking device according to the invention, on the other hand, includes a bearing block  20 , which is fixed to fixture  10  and extends over the lateral faces of wheel  18  at a distance from running face  18   f  of wheel  18  and parallel to shaft  16 , as FIGS. 1, 2 show. The two sections  201 ,  20   r  of bearing block  20  running outside the wheel carry bolts  22 , which run essentially horizontal and parallel to a wheel web  18   s  of wheel  18  carrying running face  18   f  on its peripheral side.  
         [0033]    Brake levers  241 ,  24   r  are carried in a rotary manner on bolts  22 . It can be seen from FIG. 3 in particular that the brake levers each have a shorter arm  241   o ,  24   ro  above bolts (rotary pivots)  22  than in the lower part (arms  241   u ,  24   ru ).  
         [0034]    Sections  241   u ,  24   ru  are bent inwards (towards one another) at their lower end and carry friction linings  26  there.  
         [0035]    In the assembly position, but in the state of wheel  18  when the brakes are not applied, brake levers  241 ,  24   r , or more precisely their brake linings  26 , lie as a small distance in front of wheel web  18   s.    
         [0036]    At the opposite end, i.e. in the area of sections  241   o ,  24   ro , brake levers  241 ,  24   r  are designed narrowed and in each case accommodate a transverse pin  28 , on which a bent-over end of a leaf spring  30  sits in a keyed manner. Leaf spring  30  is curved in a convex manner in relation to wheel  18  and is dimensioned such that, in the unloaded state, it holds brakes  241 ,  24   r  at a distance that corresponds to that described previously, i.e. at which friction linings  26  stand at a distance in front of the surfaces of wheel web  18   s  lying opposite.  
         [0037]    If, in the operation, spring  30  is loaded (arrow direction P in FIG. 1) by bolt (toothed spindle)  14  represented in FIG. 1, spring  30  pushes sections  241   o ,  24   ro  of brake levers  241 ,  24   r  apart. In parallel thereto, lower sections  241   u ,  24   ru  are moved in the direction towards one another, whereby they are conveyed towards the surfaces of wheel web  18   s  and brake wheel  18 .  
         [0038]    After retraction of bolt  14 , the braking position of brake levers  241 ,  24   r  is again released, since leaf spring  30  is brought back into its unloaded initial position and sections  241   o ,  24   ro  are again moved towards one another and sections  241   u ,  24   ru  again moved away from one another.