Abstract:
A device for attaching a shoe to a bicycle pedal, comprising a pedal body and a counter-member fixed to the sole of the shoe and adapted to be fitted to the body of the pedal. Attachement is achieved by means of a tooth which is carried by the counter-member and engages a recess formed in the body of the pedal so as to prevent the backwards displacement of the counter-member relative to the body of the pedal. A step carried by the counter-member cooperates in the body of the pedal and prevents the upward detachment of the counter-member.

Description:
SUMMARY OF THE INVENTION 
     The present invention relates to a device for attaching a shoe to a bicycle pedal. 
     More particularly, the invention relates to a device of the type comprising: 
     a pedal body with an upper bearing surface, 
     a counter-member which is fixed to the sole of the shoe and can be fitted on to the upper bearing surface of the pedal body, 
     rapid-attachment means for establishing firm mutual engagement of the pedal body with the counter-member, 
     the pedal body including a toe piece adapted to house a front portion of the counter-member when the pedal body and the counter-member are in the mutually coupled condition so as to prevent the upward detachment of the front portion of the counter-member from the upper bearing surface of the pedal body. 
     The object of the invention is to provide a device of the type defined above which has a simple, light structure and which enables the shoe to be locked on to to and to be released from the pedal quickly and easily. 
     According to the present invention, this object is achieved by the provision of an attachment device of the type specified above, characterised in that: 
     a) the counter-member has a step which is fixed to the member and is adapted to engage beneath a corresponding fixed step in the pedal body, the step being formed in a region of the pedal body which is spaced rearwardly of the toe piece so as completely to prevent the upward detachment of the counter-member from the upper bearing surface of the pedal body in the mutually coupled condition; 
     b) the rapid-attachment means comprise: 
     mutual coupling surfaces formed in the counter-member and in the pedal body respectively and extending essentially in planes parallel to the length of the counter-member and of the pedal body, one of the surfaces having a recess and the other a tooth which can engage in the recess in the coupled condition as a result of a movement of the counter-member relative to the pedal in a direction transverse its length, 
     a thrust member which is urged by a spring and is carried by the pedal body or by the counter-member and adapted --in the coupled condition --to exert a transverse force on the other member so as to prevent the recess and the tooth from moving apart when they are subjected to a force below a predetermined value which tends to move them apart; the member which is not provided with the thrust member having a cam surface for cooperating with the thrust member when the counter-member is fitted on to the upper surface of the pedal body so as first to cause the retraction of the thrust member and then to snap engage the tooth in the recess under the force returning the thrust member to its projecting position. 
     The device according to the invention ensures that the shoe is fixed to the pedal whatever movement occurs during pedalling. Release is achieved by a simple transverse rotary movement of the heel of the shoe away from the bicycle. 
    
    
     Further characteristics and advantages of the present invention will become clear from the detailed description which follows with reference to the appended drawings, provided by way of non-limiting example, in which: 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective view of a device according to a first embodiment of the invention, 
     FIG. 2 is a perspective view of the device of FIG. 1 during the engagement stage, 
     FIG. 3 is a side view, partially in section, of the device shown in FIG. 1, the section being taken along the longitudinal centerline of the FIG. 1 device in assembled and locked position. 
     FIGS. 4 and 5 are partially-sectioned plan views of the device of FIG. 1 in two different configurations, 
     FIGS. 6 and 7 are views corresponding to FIGS. 4 and 5, relating to a second embodiment of the device according to the invention, 
     FIG. 8 is a view taken on the arrow VIII of FIG. 6 during the engagement stage, 
     FIG. 9 is a perspective view of a third embodiment of the device according to the invention, 
     FIG. 10 is a partially-sectioned plan view of the device of FIG. 9, and 
     FIG. 11 is a side view, partially in section, of the device shown in FIG. 9, the section being taken along the longitudinal centerline of the FIG. 9 device in assembled and locked position. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to the drawings, a left-hand bicycle pedal is indicated 1 and has a body 2 which is rotatably mounted, in known manner, on a pin 3 with a threaded end 4 for connection to the respective pedal crank (not shown). 
     In the present description and in the following claims, geometric references are intended to relate to the normal operating position of the pedal mounted on the bicycle. 
     The pedal body 2 has a flat upper surface 5 on which the flat undersurface 6 of a counter-member 7 bears, in use. The counter-member 7 has three slots 8 for its fixing to the sole of a shoe 9 which can be seen in FIGS. 2 and 3. The counter-member 7 is fixed to the sole of the shoe 9 by means of screws 10 which pass through the slots 8 with the interposition of washers 11. 
     The counter-member 7 has a rounded front portion 12 which, in known manner, engages a toe piece 13 formed in the front part of the pedal body 2. 
     An anchoring block 15 is fixed to the lower surface 6 of the counter-member 7 by means of a screw 14. 
     Alternatively, the block 15 could be formed integrally with the counter-member 7. 
     The block 15 is inserted in a seat 16 formed in the rear of the pedal body 2 and, in the manner which will better be explained below, establishes the engagement of the counter-member 7 with the pedal body 2. 
     A tooth 18 is formed on one side 17 of the block 15 and has a stop surface 19 which extends perpendicular to the surface 6 of the counter-member 7. In its wall 20 which faces the side 17 of the block 15, the seat 16 of the pedal body 2 has a recess 21 which extends perpendicular to the surface 5 of the pedal body 2 and has a shape corresponding to that of the tooth 18. The stop surface 19 of the tooth 18 and the corresponding surface 22 of the recess 21 are inclined towards the rear of the pedal body 2 (see FIGS. 4 and 5) and constitute a restraint against the release of the block 15 towards the rear of the pedal. The wall 20, at the opening into the seat 16, has a connecting part 23 with a large radius of curvature which facilitates the insertion of the block 15 into the seat 16. 
     The block 15 has a step 24 in its front wall which cooperates with a corresponding step 25 formed in the facing wall of the seat 16 so as to define a stop which prevents the raising of the block 15 (see in particular FIG. 3). 
     As seen in FIGS. 4 and 5, the block 15 is generally wedge-shaped in plan and a vertical groove is formed in its inclined side 26. The wall, indicated 28 in the drawings, of the seat 16 facing the inclined side 26 of the block 15 is formed with a bore 29 which communicates at its rear end with a larger-diameter bore 30. A pin 31 is slidable in the bore 29 and has an enlarged head 32 situated in the bore 30. The bore 30 is closed at one end by a grub screw 33 and houses a helical spring 34 between the grub screw 33 and the head 32. The spring 34 urges the pin 31 towards its most outwardly projecting position defined by the abutment of its head 32 against the end of the bore 30. 
     The pin 31 has a circumferential groove 35 in its shank which, when the pin is in the position shown in FIG. 5 corresponding to the engagement of the block 15 in the seat 16, is acted on by a ball 36 situated in a hole 37 and urged towards the groove 35 by a spring 38. The ball 36 allows the pin 31 to move back into the bore 29 against the action of the spring 34 only when subjected to a force greater than a predetermined value. 
     The operation of the engagement device described is as follows. 
     The shoe 9 is engaged with the pedal 1 by the placing of the counter-member 7 on the upper surface 5 of the pedal body 2 with the front portion 12 of the counter-member 7 behind the toe piece 13. The counter-member 7 is then moved forwards, simultaneously bringing the front portion 12 into the toe piece 13 and the fixing block 15 into the seat 16. During this forward movement, the inclined surface 26 of the block 15 exerts a force on the pin 31 which overcomes the force exerted by the ball 36 and makes the pin 31 move back against the action of the spring 34. When the tooth 18 of the block 15 is in correspondence with the recess 21, the block 15 moves transversely under the action of the pin 31 and the tooth 18 thus engages the recess 21. In this condition, shown in FIG. 5, the end of the pin 31 is inserted in the groove 27 in the block 15 and the ball 36 is located in the circumferential groove 35 of the pin 31. 
     In the configuration shown in FIG. 5, the counter-member 7 is locked to the pedal body 2 whatever movement occurs during pedalling (movement forwards, backwards, upwards and inwards). 
     The counter-member 7 can be released from the configuration shown in FIG. 5 by the transverse rotation of the heel of the shoe 9 in the sense indicated by the arrow A in FIG. 5. During this movement, the counter-member 7 rotates about its front portion 12, which is held by the toe piece 13, and the block 15 exerts a force on the pin 31 which tends to make it retract. When this force exceeds a predetermined value which is sufficient to release the pin 31 from the action of the ball 36, the pin 31 moves inwardly of the bore 29. The tooth 18 is thus released from the recess 21 and it is then possible to move the shoe 9 backwards, releasing the shoe completely from the pedal. 
     FIGS. 6 to 8 show a second embodiment of an attachment device according to the present invention. The elements which correspond to those described above are indicated by the same reference numerals below. 
     The device shown in FIGS. 6 to 8 differs from that described above essentially in that the step 24 is situated on the side 17 of the block 15 instead of being in the front of the latter. As can be seen from FIG. 8, the side 26 of the block 15 and the lower part of the step 24 are connected to the lower wall of the block 15 by means of surfaces indicated 50 and 51 respectively. 
     By virtue of this shaping of the block 15, the latter can be engaged in the seat 16 by means of a downward movement of the block 15 from above, as well as by means of the forward movement described in connection with the first embodiment. In this case the shoe 9 is engaged with the pedal body 2 by the insertion of the front portion 12 of the counter-member in the toe piece 13 followed by the downward movement of the block 15 so as to insert it in the seat 16. During this movement, the connecting surface 50 urges the projecting end of the pin 31 backwards. When the block 15 is inserted in the seat 16 the action of the pin 31 brings the tooth 18 into engagement with the recess 21. 
     With reference to FIGS. 9 to 11, a third embodiment of the device according to the invention will now be described. 
     In this case, the counter-member 7 has a peripheral wall 60 at its rear end which extends vertically towards the lower side of the counter-member 7. As shown in FIG. 10, the cross-section of the wall 60 is U-shaped and can be seen to include a central portion 61 and two side arms indicated 62 and 63. The central portion 61 of the wall 60 has a lower step 64 which cooperates with a rear portion 65 of the pedal body 2 so that, together with the front portion 12 inserted in the toe piece 13, it prevents the counter-member 7 from being released upwardly from the pedal body 2. 
     In this third embodiment of the device according to the invention, the tooth 18 is formed in the arm 62 of the peripheral wall 61. The tooth 18 is inserted in the recess 21 formed in the side portion of the pedal body 2 by means of a forward movement of the counter-member 7 relative to the pedal body 2. As in the previous embodiments, the pin 31 situated in the pedal body 2 is made to retract by the arm 63 of the wall 60. 
     In this case the counter-member 7 is also released from the pedal body 2 by a movement of the shoe in the sense indicated by the arrow A in FIG. 10. 
     In the above description only the left hand pedal has been described, since the right hand pedal is specularly identical thereto.