Abstract:
The invention relates to a pedal system for bicycles that comprises a shoe insert, which can be fastened to the exterior of a shoe and provided with a detent element. The pedal system also comprises a pedal, which can be fastened to the bicycle, can rotate about an axis, and which has a seat for accommodating the detent element. Said detent element can be locked counter to elastic force inside the seat and can be released therefrom by executing a rotating movement. The seat for the detent element is formed between two seat parts which are rotationally symmetrical with regard to the pedal axis and which can be displaced away from one another counter to elastic force in the direction of the pedal axis.

Description:
FIELD OF THE INVENTION  
       [0001]     The invention relates to a pedal system for bicycles comprising a shoe insert, which can be fastened on a shoe and has a detent element, and a pedal, which can be fastened on the bicycle and can be rotated about an axis, and which pedal has a seat for the detent element, in which seat said detent element can be locked against elastic force, and from which seat same can be released by carrying out a rotating movement.  
       BACKGROUND OF THE INVENTION  
       [0002]     Pedal systems have been successful for racing bikes and mountain bikes, which pedal systems consist of shoe inserts fastened on the shoes and of pedals fastened on the bicycle. Pedals which each have locking mechanisms and which are designed correspondingly on two opposing sides, for the releasable locking of the detent element of the shoe insert, are common. Such pedal systems are known, for example, from EP-A-1 167 173 and the EP-A-O 826 589. Since these pedal systems have two locking mechanisms and thus make available two locking positions for the shoe insert, they are designed very complex and consist of many, often small components. This makes this pedal system susceptible to repairs and sets limits to the desire to have them have as low a weight as possible. Also with respect to their function these pedal systems are not optimal. The user must beforehand adjust the position of the pedal relative to the shoe insert in order to be able to carry out a locking. The shoe must under all possible circumstances, in particular in the case of a fall of the biker, be able to be quickly and easily released, even when the biker cannot release the pedal by force. Many of the known pedal systems are also in need of improvement in this regard.  
         [0003]     Thus the basic purpose of the invention is to design a pedal system of the above-mentioned type in particular in such a manner that, for locking of the detent element of the shoe insert, a beforehand positioning of the pedal is not needed, and that is designed simply and has fewer components than the known systems.  
         [0004]     The set purpose is attained inventively by the seat being formed between two seat parts, which are designed rotationally symmetrically with respect to the pedal axis, and which can be moved away from one another against elastic force in the direction of the pedal axis.  
         [0005]     An inventively designed pedal system has therefore a pedal with a seat for the detent element, which permits equally over the entire circumference a locking of the detent element. Thus the necessity of having to pay attention regarding the insertion of the shoe at a specific pedal position is no longer needed. Compared with the double locking mechanisms common from the known pedal systems, an inventive pedal system can thus also have significantly fewer components. This is advantageous for the weight and the durability of the pedal.  
         [0006]     A preferred embodiment of the invention is that the seat parts form or have receiving grooves facing one another. Thus a particularly operationally safe design can be assured.  
         [0007]     It is thereby merely necessary that one of the two seat parts can be moved against elastic force, thus supporting a simple design and reducing the number of components.  
         [0008]     A simple, advantageous and very robust design of the pedal provides that one of the seat parts is part of a first sleeve which is supported rotatably with respect to the axis of the pedal, and the other seat part is part of a second sleeve which is supported movably on the first sleeve.  
         [0009]     The pedal can be designed especially compact by the first sleeve being arranged non-movably with respect to the axis of the pedal, and the second sleeve being the one which is arranged movably against elastic force.  
         [0010]     Also the design and storing of the at least one spring has influence on the durability of operational safety of the pedal system. It is particularly favorable in this connection when at least one spring is a compression spring, which is supported with its one end on an abutment connected to the first sleeve and with its second end on the second sleeve.  
         [0011]     The first sleeve is rotatably supported in an advantageous manner by means of ball bearings directly on the axis part of the pedal.  
         [0012]     The detent element provided on the base of the shoe is designed according to a preferred embodiment, of the invention as an elongated component, which has a wedge-shaped designed area for positioning between the seat parts.  
         [0013]     Cams are sufficient for locking of the detent element, which cams are provided on the side surfaces of the detent element.  
         [0014]     Of a particularly comfortable design is the handling of an inventively designed pedal system furthermore by connecting the detent element to a control element, which acts centeringly with respect to the seat of the pedal.  
         [0015]     The control element is designed in an advantageous manner such that it has laterally extending supporting wings, the inside of which come into contact or are in contact with outer surface areas of the sleeves when the detent element is locked, which outer surface areas extend cylindrically and rotationally symmetrically with respect to the pedal axis, and which are curved with a radius, which is larger than the radius of the outer surfaces of the sleeves. The difference between the radii assures the already mentioned centering function and has moreover the advantage, that during a rotational movement in order to release the locked detent element, the supporting wings are supported in such a manner on the outer surfaces of the sleeves that they lift the detent element and free same automatically from the locked position. 
     
    
     BRIEF DESCRIPTION OF THE INVENTION  
       [0016]     The desire for few components and low weight is helped when the control element is part of the shoe insert, which part is connected directly to the shoe.  
         [0017]     Further characteristics, advantages and traits of the invention will now be described in greater detail in connection with the drawings which illustrate one exemplary embodiment and in which:  
         [0018]      FIG. 1  is an oblique view of the pedal,  
         [0019]      FIG. 2  is a longitudinal cross-sectional view of the pedal according to  FIG. 1 ,  
         [0020]      FIGS. 3 and 4  are oblique views of parts of the shoe insert,  
         [0021]      FIG. 5  is an oblique view of the shoe insert,  
         [0022]      FIG. 6  is a side view of the shoe insert,  
         [0023]      FIG. 7  is an oblique view of the pedal with a locked shoe insert,  
         [0024]      FIG. 8  is a longitudinal cross-sectional view of the pedal with a locked shoe insert,  
         [0025]      FIG. 9  is a top view of the pedal with an inserted shoe insert, and  
         [0026]      FIG. 10  illustrates a position of the shoe insert relative to the pedal during the release of the lock of the shoe insert. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0027]     The parts of the pedal system, which are provided for arrangement or fastening on the bicycle, are hereinafter identified as pedal  1 , and those parts, which are provided for fastening on a sole of the shoe, as shoe insert  12 .  
         [0028]     The design and the individual parts of the pedal  1  will now be discussed in greater detail in particular with reference to  FIGS. 1 and 2 . The pedal  1  has an axis part  2  which is fixedly screwed to the crank of a bicycle (not illustrated). The axis part  2  consists of several cylindrical sections, which are arranged concentrically to one another and have varying diameters. The axis part  2  has at its one end in a conventional manner an inner end section  2   a  with a thread for screwing of the pedal  1  to the crank of the bicycle. The end section  2   a  is followed by a first bearing section  2   b , which is followed by a second bearing section  2   c  with a smaller diameter. The last section is an outer end section  2   d , which has a smaller diameter than the second bearing section  2   c . The outer section  2   d  has a thread for screwing on a bearing nut  3  and a lock nut  4 .  
         [0029]     A sleeve  5  is rotatably supported on the bearing sections  2   b  and  2   c , which sleeve is not movable in axial direction relative to the axis part  2 . The sleeve  5  has a center section  5   a , with which it is supported on the second bearing section  2   c , and each one inner and one outer end section  5   b ,  5   c . A circular shoulder  7  in the transition area of the center section  5   a  to the inner end section  5   b  forms together with a circular shoulder  8  in the transition area of the first bearing section  2   b  to the second bearing section  2   c  a seat area for a first ball bearing  6   a . A further circular shoulder  9  in the transition area between the center section  5   a  and the outer end section  5   c  of the sleeve  5  forms together with a seat area  3   a  circulating at the bearing nut  3  a seat for a second ball bearing  6   b . The outer end section  5   c  of the sleeve  5  is designed like a hollow cylinder and has such large diameters so that the second ball bearing  6   b , the bearing nut  3  and the lock nut  4  can be positioned.  
         [0030]     The center section  5   a  of the sleeve  5  has on the outside a concentrically circular seat part  13  having an also circular receiving groove, which seat part  13  is open in direction of the inner end section  5   b . The seat part  13  forms together with a correspondingly designed second seat part  14  of a further sleeve  15  the locking point for the shoe insert  12  to be described in greater detail later on. The faces of the edge areas  13   a ,  14   a  of the seat parts  13 ,  14  face one another in alignment. The sleeve  15  is moved onto a cylindrical seat  10  on the outside of the center section  5   a  of the sleeve  5 . The cylindrical seat  10  has compared with the inner end section  5   b  of the sleeve  5   a  slightly larger diameter and is offset relative to same by a circular step  17 . The step  17  forms a stop for a shoulder  16  around the inside of the sleeve  15 . The one end of a compression spring  11  is supported on the shoulder  16 , the second end of which compression spring  11  is loaded by an adjusting nut  18 , which is screwed onto the inner end section  5   b  of the sleeve  5 . Thus it is possible to change the initial loading of the compression spring  11  by adjusting the position of the adjusting nut  18 . The end section following the supporting shoulder  16  of the sleeve  15  forms together with an area of the outer circumferential surface of the inner end section  5   b  of the sleeve a seat for the compression spring  11 .  
         [0031]     FIGS.  3  to  6  illustrate particularly well the design and arrangement of the parts of the shoe insert  12 . The main parts of the shoe insert  12  are a detent element  20  ( FIG. 3 ) and a control element  21  ( FIG. 4 ). The detent element  20  is an elongated component, which in the illustrated embodiment has a cavity over its longitudinal extent in order to reduce its weight. The detent element  20  has side surfaces  20   c , which extend parallel to one another, are of the same size and are designed in the form of equal-sided trapezoids, a rectangular upper side  20   b  and faces  20   a  with wedge-shaped converging side edges so that the underside opposite the upper side  20   b  is formed by two wedge surfaces  20   d . A cam  22  is provided centrally on each side surface  20   c . Two screw holes  23  for connecting of the detent element  20  to the control element  21  and two recesses  24  can be recognized on the upper side  20   b  of the detent element  20 , which recesses  24  make available space for screw heads of screws  23  (see  FIG. 8 ) for fastening of the control element  21  to the shoe (not illustrated).  
         [0032]     The control element  21  consists of a center base part  21   a , which has the screw holes  26  for connecting to the detent element  20  and the screw holes  27  for connecting of the element  21  to the shoe. Supporting wings  21   c  follow the base part  21  through slightly inclined connecting surfaces  21   b , the underside of which supporting wings  21  is curved along arches, the radii of which are slightly larger than the radius of the outer surface of the outer end section  5   c  of the sleeve  5  or the radius of the outer surface of the sleeve  21 , the radii of which correspond in the illustrated embodiment. The control element  21  and the detent element  20  are furthermore in the illustrated embodiment components symmetrically designed with respect to their longitudinal and transverse axes. The detent element  20  screwed to the underside of the base part  21   a  projects beyond the lateral supporting wings  21   c  of the control element  21 .  
         [0033]     FIGS.  7  to  10  illustrate the shoe insert  12  in its position inserted on the pedal  1 , the cams  22  grip under the edge areas  13   a ,  14   a  of the seat parts  13 ,  14  and the supporting wings  21   c  contact centrally the outsides of the sleeves  5  or  15 .  
         [0034]     The inventive pedal system does not only have a simple design but is also especially functional. In order to lock the shoe insert  12  on the pedal  1 , the pedal  1  does not need to assume a particular position; a locking of the detent element  20  in the seat formed between the seat parts  13 ,  14  is equally possible over the entire circumference of the pedal  1 . The biker must merely position the detent element  20  between the two parts  13 ,  14  and lock same by applying a certain force. The wedge surfaces  20   d  of the detent element  20  make positioning of the same easier. The sleeve  15  is during the locking operation moved against the force of the spring  11  by the cams  22 . When the two cams  22  are within the edge areas  13   a ,  14   a , the sleeve  15  is returned again into its initial position. The shoe insert  12  is therefore frictionally connected to the pedal  1  so that the pedal system can be stressed both for pull and also pressure. Due to their particular design, the two supporting wings  21   c  perform, during the insertion of the detent element  20 , a control function to center the detent element  20 , which, if necessary, is initially positioned off-center (in relationship to the longitudinal axis of the pedal  1 ).  
         [0035]     The release of the shoe insert  12  from the pedal  1  is possible quickly and without any problems under all possible conditions—also in the case of a fall of the biker. Even when a force is applied from the shoe onto the pedal  1 , a quick release of the shoe from the pedal  1  is guaranteed by a turning of the shoe into one of the two directions. A turning of the shoe and thus of the shoe insert  12  has the consequence that, as illustrated in  FIG. 10 , the detent element  20  moves the sleeve  15  against the force of the spring  11  and enlarges the opening between the seat parts  13 ,  14  so wide that the detent element  20  can come free. The supporting wings  21   c , which slide on the outer surfaces of the sleeves  5  and  15 , and cause at the same time due to the mentioned varying radii a lifting of the shoe insert  12  relative to the pedal  1 . The components, which participate in these sequences of movement, are therefore designed and adjusted to one another in particular in such a manner that after a comparatively small angle of rotation of, for example, approximately 10°, the cams  22  are already on the faces of the edge areas  13   a ,  14   a  of the parts  13 ,  14 . The detent element  20  is in this manner automatically freed from the locking.  
         [0036]     The invention is not limited to the illustrated exemplary embodiment. Thus, it is, for example, possible to design the pedal  1  in such a manner that selectively one of the sleeves is arranged movably against the spring force or also that both sleeves are movable. Instead of one spring it is furthermore also possible to provide several springs.