Abstract:
The skate assembly includes a bogie frame including a brake pad, a pad support and a wear compensation system. Such a system includes an articulation, enabling the pad support to be lifted relative to the rest of the frame, and a movable locking lever. During braking, the lever is fastened into the slots provided for fastening the lever. When the pad has worn out, the user can unlock the lever and rotate the support so as to bring again the pad close to the ground. In this way, notwithstanding the wear of the pad, the need for excessively tilting the skate for braking is avoided. The adjustment system is very simple from the manufacturing standpoint, and is easy and quick to lock.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to a roller skate assembly with a braking device, equipped with a system for compensating the wear of the brake pad.  
       STATE OF THE ART  
       [0002]     The problem of braking the wheels in order to stop the roller skate or to adjust the speed thereof is currently felt in conventional roller skates, whether constituted by a shoe associated with a supporting frame for two pairs of mutually parallel wheels, or by a shoe associated with a supporting frame for multiple in-line wheels.  
         [0003]     Conventional skates are equipped with pads or blocks, usually made of rubber and secured to supports that are located close to the heel or tip region of the shoe.  
         [0004]     When the user tilts the shoe backwards or forwards, respectively, depending on the brake type, the pad interacts with the ground and performs braking.  
         [0005]     Yet, in several conventional skate models, the support on which the pad is mounted is integral or rigidly coupled with the rest of the wheel-supporting frame and, as the pad wears down, the user, in order to brake, must tilt the skate more and more, with consequent difficulty in keeping balance.  
         [0006]     In order to solve that problem, European Patent Application EP 687 487 proposes a system for adjusting the distance of the braking surface of the brake pad relative to ground, so as to compensate the pad wear. According to that solution, the brake pad is secured to a pivoting support pivotally connected to the rest of the skate so as to pivot about the rotation axis of the rearmost skate wheel. The tilt of the pivoting support is adjusted by an assembly of two toothed bars or levers and a locking cam lever. Yet, in such a system, depending on the design and the manufacturing tolerances, the cam lever may spontaneously unlock while the skate is being used, or it can be too stiff and difficult to open while keeping the skate on. Generally, the cam locking system requires, for a good operation, considerably precise working tolerances. Such a difficulty increases if the skate is to be manufactured by molding and generally at low cost as a mass product.  
         [0007]     It is an object of the present invention to provide a system for compensating the wear of the brake pad of a roller skate, which system is easier and handier to unlock and lock if compared with the prior art system described above.  
       SUMMARY OF THE INVENTION  
       [0008]     The above object is achieved, according to the invention, through a roller skate assembly having the features as claimed in claim  1 .  
         [0009]     The advantages afforded by the present invention will become more apparent to the skilled in the art from the following detailed description of a particular and non-limiting exemplary embodiment, given with reference to the following schematic Figures. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]      FIG. 1  is a side view of a roller skate equipped with an embodiment of the braking system according to the invention, with the locking lever in unlocked condition;  
         [0011]      FIG. 2  is a side view of the skate of  FIG. 1 , with the locking lever in locked condition;  
         [0012]      FIG. 3  is a side view of a detail of the locking lever of the wear compensation system of the skate of  FIG. 1 ;  
         [0013]      FIG. 4  is a perspective view of the heel portion of the skate of  FIG. 1 . 
     
    
     DETAILED DESCRIPTION  
       [0014]     In  FIG. 1 , reference numeral  1  generally denotes a roller skate with in-line wheels according to an embodiment of the present invention. In the present description, the term “in-line wheels” is to be intended as meaning that wheels  9  enabling the skate to roll on ground T are arranged in a single row parallel to the rolling direction of the same wheels.  
         [0015]     Skate  1  comprises a boot or skate shoe  3  and a bogie frame, generally denoted by reference numeral  5 , arranged to secure and support shoe  3  on its top portion. Bogie frame  5  also defines, in its bottom portion, a bogie portion  7  to which there are secured a plurality of wheels  9 , enabling skate  1  to rest and roll upon the ground, a floor or another rolling surface T.  
         [0016]     In the present exemplary embodiment, bogie frame  5  is also equipped, in its rear portion, of a brake  11  comprising a brake pad  17 , made for instance of an elastomeric or suitably soft material, and a pad support  19  to which pad  17  is secured. Roller skate  1  further includes a wear compensation system  13  enabling reversibly adjusting the distance of brake pad  17  from ground T and the pad position relative to the rest of bogie frame  5 , so as to compensate the reduction in the volume of pad  17  caused by wear during use. Such a wear compensation system  13  includes a pivotal connection  15  ( FIG. 4 ) by means of which pad support  19  is secured the rest of bogie frame  5  so as to be pivotable (arrow FS in  FIG. 2 ) about a pivotal axis coinciding, in the present example, with horizontal rotation axis AR ( FIG. 4 ) of rearmost wheel  9 .  
         [0017]     According to the present invention, wear compensation system  13  further includes a position adjustment system, which in turn includes locking lever  21  (in the present exemplary embodiment pivotally mounted in a region below the heel of bogie frame  5 ) and the plurality of fastening slots  23  arranged in the top portion of pad support  19 . Locking lever  21  includes, in the present exemplary embodiment, a locking tooth  25  and a grasping tongue or a grasping extension or part  27 .  
         [0018]     By pivoting about rotation axis AL ( FIGS. 3, 4 ), lever  21  can reversibly move from an unlocking position ( FIG. 1 ), in which support  19  freely rotates about rotation axis AR of rearmost wheel  9  relative to the rest of bogie frame  5 , to a locking position ( FIG. 2 ), in which such rotation of support  19  is prevented. To move from the locking position to the unlocking position, lever  21  turns in a so-called “unlocking” direction, that is, with reference to the views of  FIGS. 1 and 2 , it turns in clockwise direction, as shown by arrow FL 1 . Conversely, to move from the unlocking position to the locking position, lever  21  turns in a so-called “locking” direction, that is, with reference to the views of  FIGS. 1 and 2 , it turns in counterclockwise direction, as shown by arrow FL 2 . Locking lever  21  and fastening slots  23  are so shaped that they mutually engage so as to substantially prevent a mutual pivotal movement between pad support  19  and the rest of bogie frame  5  due to the push of pad  17  during braking.  
         [0019]     According to the present invention, locking lever  21  and fastening slots  23  are moreover so shaped that, due to the push of pad  17  during braking (arrow FS in  FIG. 2 ), locking lever  21  is pushed further in the locking direction, or at least is maintained in the locked condition, against the portion of support  19  adjacent to lever  21  itself.  
         [0020]     In order to obtain that effect, in the exemplary embodiment of FIGS.  1  to  4 , lever  21  and support  19  are so arranged and shaped that pad support  19 , when it tends to rotate to become lifted and presses against tooth  25  inserted in a slot  23  during braking, causes tongue  27  to rest against support  19  itself, thereby preventing further counterclockwise rotation of lever  21  and hence further clockwise rotation of support  19 . The forces applied by support  19  to lever  21  in locked condition and during braking produce a resultant moment on lever  21  tending to more strongly fasten the lever to support  19 .  
         [0021]     Moreover, according to the present invention: 
        pivotal connection  15  may be more generally replaced by an articulation, where the latter term in the present description is intended to include also articulated joints or other mechanical connections enabling also telescopic extensions and/or movements of mere translational nature of pad support  19  relative to the rest of bogie frame  5 , and not only rotational or roto-translational movements;     lever  21  may be more generally replaced by a movable fastening member  21  arranged to reversibly move from a locked condition, in which pad support  19  substantially cannot be lifted or lowered relative to the rest of bogie frame  5 , to an unlocked condition, in which pad support  19  substantially can be displaced relative to the rest of bogie frame  5 , wherein movable fastening member  21  can move to the locked condition by moving in a locking direction, e.g. through the counterclockwise rotation discussed above, and can move to the unlocked condition by moving in an unlocking direction, e.g. through the clockwise rotation discussed above;     the plurality of slots  23  may be more generally replaced by a fastening part  23 ;     movable fastening member  21  and fastening slots  23  are arranged to mutually engage so as to prevent the displacement of pad support  19  caused by the push of brake pad  17  during braking, and are further arranged so that, when they are mutually engaged, movable fastening member  21  is pushed further towards or in any case kept in the locked condition due to the push of brake pad  17  during braking. Consequently, during braking, lever  21 , or another movable fastening member  21 , is kept in the locking position by the same forces as applied by pad  17  to pad support  19 . Thus, the position adjustment system can be made with a very simple and little cumbersome mechanical construction, if compared e.g. to the solutions disclosed in documents EP 687 487 A2 or U.S. Pat. No. 5,741,017, and by using few components, while providing a robust and reliable fastening.        
 
         [0026]     Preferably, but not necessarily, locking tooth  25  has an height H ( FIG. 3 ) that substantially is not lower than about 2 mm. More preferably, height H of locking tooth(s)  25  is not lower than about 3 mm. Still more preferably, height H of locking tooth(s)  25  is not lower than about 4 mm.  
         [0027]     In the exemplary embodiment of  FIG. 3 , locking tooth  25 , or another locking projection  25  of movable fastening member  21 , has a contact surface  31  onto which pad support  19  pushes during braking thereby discharging the braking forces. Preferably, but not necessarily, contact surface  31  is so arranged, more particularly inclined, that the resultant of the forces applied to it by support  19  tend to rotate the tooth downwards or, more generally, to push tooth  15  towards the locking position. In the exemplary embodiment of FIGS.  1  to  4 , the resultant of the forces applied to contact surface  31  by support  19  passes in a space region between rotation axes AL of lever  21  and AR of pad support.  
         [0028]     Such features of tooth  15  improve the fastening reliability.  
         [0029]     An exemplary operation and use of the wear compensation system described above is now disclosed.  
         [0030]     In use, wear compensation system  13 , and in particular lever  21 , is in its locking position illustrated in  FIG. 2 .  
         [0031]     Assuming that, after a certain period of use, pad  17  has worn out and the surface by which it rubs against ground T during braking corresponds, with reference to the side view of  FIG. 2 , to dashed line L 2  instead of solid line L 1 , in turn corresponding to the ground-rubbing surface of a pad when new, the user decides to adjust pad  17  to a position closer to ground, so that he/she is to raise the tip of skate  1  with a reduced tilt when braking.  
         [0032]     To this end, the user lifts locking lever  21  by its fingers, by grasping it by means of grasping tongue  27  and turning it upwards, with reference to  FIGS. 1 and 2 . Tooth  25  comes out of fastening slot  23  in which it was inserted, and releases pad support  19 . The user can now turn pad support  19  in counterclockwise direction about the pivotal axis of the support (which, as said, coincides in the present example with the rotation axis of rearmost wheel  9 ) so as to bring the pad closer to ground T to the extent the user deems suitable for compensating the size reduction caused by wear, and to bring tooth  25  in correspondence of the most suitable fastening slot  23 . When grasping tongue  27  is released, return spring  29  ( FIG. 3 ) pushes lever  21  downwards, thereby fastening tooth  25  into a new fastening slot  23  and firmly locking pad support  19  with the desired inclination relative to the line of wheels  9  and generally relative to the rest of bogie frame  5 . Clearly, the different fastening slots  23  are arranged at a suitable mutual spacing, corresponding to a wear amount that is optimum for a new positioning of pad support  19  by means of the compensating device. In an embodiment not shown, pad  17  has one or more notches or other marks, each corresponding to a pad wear limit whose attainment makes it advisable, according to the manufacturer, to move pad support  19  to a new position by means of the compensating device.  
         [0033]     It is apparent from the above description that the invention allows making a system for adjusting the position of a brake pad in skates, which system does not demand particularly precise working tolerances and also enables making position adjustment systems that can be locked and unlocked in an easier, quicker and handier manner if compared to the systems disclosed e.g. in documents EP 687 487 A2 and U.S. Pat. No. 5,741,017. Such handiness also results from the fact that return spring  29 , rather than to keep tooth  25  in slots  23  during braking, is primarily intended to: a) ensure that lever  21  is fastened again when adjustment has ended; and b) keep tooth  25  firmly fastened in slots  23  when the brake pad is not being used. Thus, it is sufficient that return spring  29  applies relatively weak forces, so that releasing lever  21  is handy for the user.  
         [0034]     Several changes and modifications can be made to the exemplary embodiments described above, without departing from the scope of the present invention.  
         [0035]     For instance, an assembly according to the present invention may be used for making not only a roller skate with in-line wheels, but also a roller skate whose wheels are not in line, such as the more traditional roller skates with four wheels arranged at the corners of a rectangle. Fastening slots  23 , or another fastening part  23 , may also be arranged on a bogie frame portion different from pad support  19 , and not only on pad support  19 . Moreover, fastening slots  23  may be replaced by a fastening part  23  of different kind, e.g. by teeth or projections instead of slots or recesses. Pivoting lever  21  may be replaced by a different kind of movable fastening member, e.g. a rotating cam, a rotating balance, a tooth or a moving pin, e.g. removably mounted, a translating cam. In order to engage fastening part  23 , movable fastening member  21  may be equipped with a suitable recess, opening or hole in place of tooth  25  or other kind of projection. Furthermore, movable fastening member  21  may rest against pad support  19 , or another fastening part  23 , not only by means of grasping portion  27  but also by means of a different kind of suitably shaped projection or recess. While in the example of  FIG. 3  locking lever  21  is indicatively Y- or fork-shaped, in other embodiments it may have a different shape, e.g. an L, T, cross or more or less rounded shape. The lever or other movable fastening member  21 , and/or pad support  19 , may move from the locked to the unlocked condition, and vice versa, not only through a rotation relative to each other and relative to the rest of bogie frame  5  of the skate, but also through a translational or roto-translational movement. In the embodiment of FIGS.  1  to  4 , lever  21  has a single tooth  25 , but in other embodiments it may have multiple fastening teeth or projections  25 , e.g. two, three or four teeth or projections. Return spring  29  may be replaced by a different return member, e.g. a different kind of resilient member. Of course, brake pad  17  and pad support  19  may be integrally formed as a single piece, for instance by simultaneous molding.