TRAVELING AND ACCELERATING SYSTEM FOR BICYCLE

Abstract: A traveling and accelerating system for bicycles includes a frame having a front wheel at a front part and a rear wheel at a rear part thereof; a pair of pedals fixed at both sides of a shaft which is rotatably supported at a boss being fixed under a center of the frame, to be driven by a user's feet; a driving sprocket axially fixed on the shaft for transmitting rotation power via a chain to the rear wheel; a housing attached at one side of the boss to be closed with a cap and having a hollow cross-sectional shape to accommodate accessories; a pinion axially fixed on the shaft beside the driving sprocket in the housing; a first gear member accommodated in the housing and having an inner gear part along its inner diameter; a second gear member movably contacted the first gear member and provided with planetary gears to be engaged with the inner gear part of the first gear, the planetary gears being fixed by pins and rotatable with relation to the pins; latch means respectively inserted in the first gear member and the second gear member for rotating them respectively in one direction; and a conversion control part connected to a release cable outside the housing for setting a travel mode or an acceleration mode corresponding to rotation directions of pedals by controlling engagement of the first gear member and the second gear member according to the user's selection.

Description: TRAVELING AND ACCELERATING SYSTEM FOR BICYCLE BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a traveling and accelerating system for bicycles, and more particularly to, an improved traveling and accelerating system for bicycles by which the bicycle may travel forward regardless of rotation direction of pedals and accelerated travel is also possible without any change gears . Description of the Prior Art In general, bicycles include front and rear wheels, pedals to generate power by being stepped by a user, and a power transmission means to transfer the power generated by rotation of the pedals to the rear wheel. The power transmission means includes a driving sprocket mounted at the pedals, a driven sprocket having a latch for transmit power toward the rare wheel in one direction, and a chain to connect the driving sprocket to the driven sprocket. The driven sprocket is provided with a latch member to be engaged with the rear wheel only in one direction. As described above, the conventional bicycle travels only in one direction, that is, in the forward direction by rotation power which is generated by rotating the pedals forward and transmitted through the chain connecting the driving sprocket to the driven sprocket. Therefore, the user has to rotate the pedals only in the forward direction, and such a same movement makes the user's leg-muscles unbalanced and makes the user feel bored and tired easily, while it is impossible to relieve his fatigue while riding the bicycle. In the conventional traveling device, even though it is possible to stop rotation of the pedals or rotate the driving sprocket and the chain reversely in response to reverse rotation of the pedals, the power is cut off and not transmitted by a forward latch means provided inside the driven sprocket so that the driven sprocket races. In order to resolve the above disadvantages, Korean Patent Publication No. 95-13589 has suggested a reverse traveling device which includes a forward clutch to alternatively transmit driving power to a driving sprocket, a feed shaft of which engagement state is changeable by means of an operation lever, an idle gear and a reversing gear wheel, so that the bicycle may travel forward even in case of backward rotation of the pedals, developing the user's feet and legs in balance. The reverse traveling device has, however, still problems that the structure thereof is too complicated and this reverse traveling device cannot be adapted to the driving wheel at the driven sprocket side of the currently widespread bicycles, so that a new bicycle should be purchased. Furthermore, such a proposed reverse traveling device has no change gear, so that there is a tendency to avoid use of it. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a traveling and accelerating system for bicycles which may transmit power in case of not only forward rotation but also backward rotation of pedals. It is another object of the present invention to provide a traveling and accelerating system for bicycles which may operate in both forward and backward directions of pedal rotation so that users may develop their leg- muscles in balance and feel little bored and tired while riding the bicycle. It is a further object of the present invention to provide a traveling and accelerating system for bicycles which is provided with a change gear integrally for accelerated traveling so that an additional change gear is not necessary any more and users may purchase a bicycle at a relatively low cost. To achieve the above objects, the present invention is directed to a traveling and accelerating system for bicycles which includes a frame having a front wheel at a front part and a rear wheel at a rear part thereof; a pair of pedals fixed at both sides of a shaft which is rotatably supported at a boss being fixed under a center of the frame, to be driven by a user's feet; a driving sprocket axially fixed on the shaft for transmitting rotation power via a chain to the rear wheel; a housing attached at one side of the boss to be closed with a cap and having a hollow cross-sectional shape to accommodate accessories; a pinion axially fixed on the shaft beside the driving sprocket in the housing; a first gear member accommodated in the housing and having an inner gear part along its inner diameter; a second gear member movably contacted the first gear member and provided with planetary gears to be engaged with the inner gear part of the first gear, the planetary gears being fixed by pins and rotatable with relation to the pins; latch means respectively inserted in the first gear member and the second gear member for rotate them respectively in one direction; and a conversion control part connected to a release cable outside the housing for setting a travel mode or an acceleration mode corresponding to rotation directions of pedals by controlling engagement of the first gear member and the second gear member according to the user's selection. According to the traveling and accelerating system for bicycles of the present invention, the user may simply change the pedals' rotation direction forward and backward by operating the conversion lever while keeping forward traveling of the bicycle, thereby promoting balanced development of leg-muscles. Also, it becomes possible to selectively accelerate traveling speed by increasing rotation number with relation to a certain rotation. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will become more fully understood from the detailed description given hereinafter and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: Fig. 1 is a disassembled perspective view showing the construction of principal parts of a traveling and accelerating system for bicycles according to the present invention; Fig. 2 is a partially taken unfolded view showing the construction of the traveling and accelerating system for bicycles according to the present invention, which is in an assembled state; Fig. 3 is a partially taken unfolded operational view for explaining forward normal travel mode in case of stepping pedals forward; Fig. 4 is a partially taken unfolded operational view for explaining accelerated travel mode in case of stepping pedals forward; Fig. 5 is a partially taken unfolded operational view for explaining forward accelerated travel mode in case of stepping pedals backward; Fig. 6 is a perspective view showing the construction of principal parts of a traveling and accelerating system for bicycles according to the present invention, in which a conversion control part is set to a forward normal travel mode; Fig. 7 is a perspective view showing the construction of principal parts of a traveling and accelerating system for bicycles according to the present invention, in which a conversion control part is set to a forward accelerated travel mode; and Fig. 8 is a perspective view showing the construction of principal parts of a traveling and accelerating system for bicycles according to the present invention, in which a conversion control part is set to a backward accelerated travel mode. DETAILED DESCRIPTION OF THE INVENTION Fig. 1 to Fig. 8 show a construction of a traveling and accelerating system for bicycles according to an embodiment of the present invention, in which clutch bearings are adapted as forward and backward latch means . Fig. 1 is a disassembled perspective view showing the construction of principal parts of a traveling and accelerating system for bicycles according to the present invention, and Fig. 2 is a partially taken unfolded view showing the construction of the traveling and accelerating system for bicycles according to the present invention, which is in an assembled state. Fig. 3 is a partially taken unfolded operational view for explaining forward normal travel mode according to a selection of a conversion control part 100, Fig. 4 is a partially taken unfolded operational view for explaining accelerated travel mode by a selection of the conversion control part 100, and Fig. 5 is a partially taken unfolded operational view for explaining forward accelerated travel mode in case of stepping pedals 20 backward by a selection of the conversion control part 100. Fig. 6 to Fig. 8 are perspective views respectively showing principal parts of the traveling and accelerating system for bicycles according to the present invention, in which it is apparent to understand the movement of moving plates for controlling clutches according to the selections of the conversion control part 100. The bicycle includes a frame 10 forming a frame body of the bicycle, front and rear wheels, which are not shown but provided rotatably to the frame 10, and a boss 21 fixed to mount the pedals 20 under a center of the frame 10 to support rotation of the pedals 20. The pedals 20 are fixed inside the boss 21 and a shaft 22 is rotatably inserted through the inside of the boss 21 by means of bearings (unshown) . Therefore, when a user steps the pedals 20 at both sides of the boss 21, rotational power is transmitted to the shaft 22 so that the rotational power drives a driven sprocket (unshown) at the rear wheel via a chain 31 by means of the driving sprocket 30 which is axially mounted on the shaft 22, thereby the bicycle traveling forward. The driving sprocket 30 which is axially mounted on the shaft 22 is positioned in a housing 40 to transmit the rotational power via the chain 31. The housing 40 is fixed on the frame 10 at one side of the boss 21 and closed with a cap 41 at its opening, accommodating various accessories therein, so that external impurities may be prevented from being introduced therein and viscosity of oil which is necessary for operating the accessories may be protected. The housing 40 accommodates the driving sprocket 30, a pinion 50, the first gear member 60, and the second gear member 70 therein. That is, in the housing 40, the pinion 50 is axially fixed on the shaft 22 at one side of the driving sprocket 30 to rotate together with the driving sprocket 30. A clutch 80 for preventing reverse-driving is fixedly interposed between the driving sprocket 30 and the pinion 50, thereby rotating together with the driving sprocket 30 and the pinion 50. The clutch 80 for preventing reverse-driving moves to rotate separately when the second gear member 70 and the driving sprocket 30 are coupled each other and the pedals 20 are stepped forward. To the contrary, if the pedals 20 are stepped backward, the clutch 80 rotates together with the driving sprocket 30 by means of a below-mentioned bearing clutch. The housing 40 accommodates the first gear member 60 formed with an inner gear part 62. The inner gears 62 of the first gear member 60 are engaged with planetary gears 74 of the second gear member 70, and the planetary gears 74 are mounted by means of a pin 75 and rotatable with relation to the pin 75 in the housing 40. The sleek inner peripheral 62 of the first gear member 60 has a peripheral formed without teeth, so that a clutch bearing 91 is inserted on the inner peripheral, the clutching bearing 91 being provided with a plurality of balls 91c and springs 91d in a predetermined interval. The second gear member 70 is also inserted with a clutch bearing 92 in the same member manner with the first gear member 60. The clutch bearings 91 and 92 are respectively formed with a plurality of grooves 91a and 92a in a predetermined interval and have slanted surfaces 91b and 92b respectively, so that the balls 91c and 92c and the springs 91d and 92d are respectively fitted into the grooves 91a and 92a. Therefore, when rotation direction of the clutch bearings 91 and 92 is different from that of the first and second gear members 60 and 70, that is, different from that of the slanted surfaces 91b and 92b, the balls 91c and 92c slide along the slanted surfaces 91b and 92b into positions where a distance from the first and second gear members 60 and 70 to the slanted surfaces 91b and 92b becomes narrow. Then, the balls 91c and 92c are closed in the narrow space between the clutch bearings 91 and 92 and the first and second gear members 60 and 70, so that the clutch bearings 91, 92 and the first and second gear members 60 and 70 become coupled integrally, thereby being controlled to rotate respectively in one direction. Detailed description with regard to the operation of the clutch bearings 91 and 92 is omitted since it has already been widely known in the routine mechanical fields. Since the slanted surface 91b of the clutch bearing 91 is formed in an opposite direction to the slanted surface 92b of the clutch bearing 92, the first gear member 60 and the second gear member 70 are controlled to rotate in a different direction from each other. As the pedals 20 are stepped, the first gear member 60 and the second gear member 70 are selectively driven. In this case, the planetary gears 74 control traveling speed of the bicycle, for example, in 1 : 1 Forward Traveling Mode, Accelerated Traveling Mode or Backward Traveling Mode. A conversion control part 100 is mounted outside the housing 40 to selectively control the latch member 85 to function in the 1:1 Forward Traveling Mode, Accelerated Traveling Mode or Backward Traveling Mode. The conversion control part 100 controls the traveling by fixing any one or both of the first and second gear members 60 and 70 not to rotate, or by making them rotate freely. A lever 110 is positioned through outside and inside of the housing 40 and connected with the release cable 104 which is provided at a convenient position with the user, for example, a position around a handle of the bicycle, so that the user may change a position of the lever 110 by means of the release cable 104, thereby controlling the rotation of the first gear member 60 and the second gear member 70 by means of a forward driving clutch bearing 130 and a backward driving clutch bearing 140. The forward driving clutch bearing 130 and the backward driving clutch bearing 140 are respectively positioned in the housing 40 and in the cap 41 to perform the 1:1 Forward Traveling Mode, Accelerated Traveling 10 Mode or Backward Traveling Mode by fixing or releasing outer diameters of the first gear member 60 and the second gear member 70. The lever 110 is connected at its one end part to a conversion selection lever (unshown) and the release cable 104 which is positioned around the handle of the bicycle, so that rotation angle of the lever 110 is converted by a wire which is pulled in response to manipulation of the conversion selection lever. In this case, the function of the forward driving clutch bearing 130 and the backward driving clutch bearing 140 correspond to that of the above clutch bearings 91 and 92. The first gear member 60 has the sleek inner peripheral 62 without teeth, so that the clutch bearing 130 is inserted in the inner peripheral 62, the clutch bearing 130 being provided with a plurality of balls 131c and springs 131d in a predetermined interval. The second gear member 70 is also inserted on its outer diameter with the clutch bearing 140 in the same member manner with the first gear member 60. The clutch bearings 130 and 140 are respectively formed with a plurality of grooves 131a and 142a in a predetermined interval and have slanted surfaces 131b and 141b respectively, so that the balls 131c and 141c and the springs 131d and 141d are respectively fitted into the grooves 131a and 141a. Therefore, when rotation direction of the clutch bearings 130 and 140 is different from that of the first and second gear members 60 and 70, that is, different from that of the slanted surfaces 131b and 141b, the balls 131c and 141c slide along the slanted surfaces 131b and 141b into positions where a distance from the first 11 and second gear members 60 and 70 to the slanted surfaces 131b and 141b becomes narrow. Then, the balls 131c and 141c are closed in the narrow space between the clutch bearings 130 and 140 and the first and second gear members 60 and 70, so that the clutch bearings 130, 140 and the first and second gear members 60 and 70 become coupled integrally, thereby being controlled to rotate respectively in one direction. The rotation of the first gear member 60 and the second gear member 70 is controlled by clutch pins 151, 161 of moving plates 150, 160 which move in response to position change of the lever 110 and control positions of the balls 131c, 141c, thereby performing the Forward Traveling Mode, Accelerated Traveling Mode or Backward Traveling Mode. The lever 110 is elastically mounted by a spring 111 and controlled its position according to manipulation of the user by means of the release cable 104, thereby performing the Forward Traveling Mode, Accelerated Traveling Mode or Backward Traveling Mode. The clutch pins 151, 161 of the moving plates 150, 160 are protruded toward the balls 131c, 141c. The moving plates 150, 160 are elastically installed on a hook protrusion 163 to return to initial positions if external force of the spring 133 is not applied, and have protrusions 156, 166 to be inserted to grooves 112, 113 of the rotatably mounted lever 110. Therefore, as the protrusions 156, 166 moves by the lever 110, the clutch pins 151, 161 controls the positions of the balls 131c, 141c and the coupling state of the clutch bearings 130, 140 and the first gear member 60 and the second gear member 70 to perform the travel modes . 12 In order to prevent possible damage caused by inside load of the housing 40, a bracket 140 is provided and a thrust bearing 171 is preferably provided in the contact portions with the housing 40 and the cap 41. Now, operation by steps will be described in more detail . (Forward Normal Travel) Referring to Fig. 3 to Fig. 6, since the lever 110 connected to the release cable 104 is not pulled yet by the manipulation of the user, the lever 110 is in a most slanted position so that the protrusions 156, 166 are separated to both end parts. Therefore, the clutch pins 151, 161 push the balls 131c, 141c into the deepest position of the slanted surfaces 131b, 141b. Therefore, if the user steps the pedals 20 in the clockwise direction as shown by an arrow in Fig. 3, the clutch bearings 91 and 92 coupled in a neutral position of the shaft 22 rotate in a same direction, since the first and second gear members 60 and 70 are not engaged with the clutch bearings 130 and 140. Since the balls 92c are closed between the slanted surfaces 92b of the clutch bearing 92 and the second gear member 70 and the balls 91c are closed between the opposite slanted surfaces 91b of the clutch bearing 91 and the first gear member 60, the clutch bearings 91 and 92 become coupled with the first and the second gear members 60 and 70 integrally, preventing backward rotation of the first gear member 60. The planetary gears 74 ovably mounted to the second gear member 70 are engaged with the inner gear 62 of the first gear member 60, so that it becomes impossible for the planetary gears 74 to rotate. 13 Therefore, when the pedals 20 are stepped by the user for forward traveling, the latch member 85 which is coupled with the first gear member 60 and the second gear member 70 rotates, so that the planetary gears 74 supported by the pins 75 race and the pinion 50 which is fixed by the driving sprocket 30 rotates in the clockwise direction, being engaged among the planetary gears 74, thereby the driving power being transmitted to the rear wheels via the chain 31. In this case, if the user stops stepping the pedals 20 or steps the pedals 20 backward, the latch 82 of the latch member 85 rotates in a direction to be released from the latch gear 73 of the second gear member 70, so that the stopping of the rotation of the pedals 20 while traveling the bicycle or backward stepping of the pedals 20 become possible without transmitting the power. (Accelerated Forward Traveling) As shown in Fig. 4 and Fig. 7, according to manipulation of the lever positioned around the handle, the lever 110 connected to the release cable 104 becomes positioned in the center. In this case, if protrusions 156, 166 of the lever 110 drive the clutch bearing 130 to control the first gear member 60, the clutch pin 151 of the moving plate 150 elastically moves the ball 131c into the deepest position of the slanted surface 131b by the spring 131d. Therefore, the first gear member 60 is fixed and only the second gear member 70 is rotatable, so that the clutch bearings 91 and 92 rotate in the same direction as the pedals 20 are stepped in a direction of an arrow of Fig. 5 for forward travel. 14 Since the slanted surface 91b of the clutch bearing 91 is formed in an opposite direction to the slanted surface 92b of the clutch bearing 92, the first gear member 60 and the second gear member 70 are controlled to rotate in a different direction from each other. The planetary gears 74 movably mounted to the second gear member 70 are engaged with the inner gear 62 of the first gear member 60. When the second gear member 70 rotates, the planetary gears 74 race in response to the rotation of the second gear member 70 since a common center of the planetary gears 74 rotates in the same direction with the second gear member 70. Simultaneously, the planetary gears 74 rotate by the inner gear 62 of the first gear member 60, so that the pinion 50 being engaged among the planetary gears 74 obtains a rotation number which is increased by both racing and the rotation of the planetary gears 74. Therefore, when the pedals 20 are stepped by the user for forward traveling, the latch member 85 and the clutch bearing 92 which are coupled with the second gear member 70 rotates in the same direction with the second gear member 70, so that the pinion 50 which is coupled with the driving sprocket 30 is accelerated in its rotation by a speed ratio of the planetary gears 74 positioned between the inner gear 62 of the stopped first gear member 60 and the pinion 50, thereby the driving power being transmitted to the rear wheels via the chain 31. (Backward Normal Traveling) As shown in Fig. 5 and Fig. 8, if the user manipulates the lever 110 connected to the release cable 104 most perpendicularly, the protrusions 156, 166 move 15 to a most center position and the clutch pins 151, 161 of the moving plates 150, 160 moves the balls 131c, 141c to the lowest position of the slanted surfaces 131b, 141b by the elastic force of the springs 131d, 141d. Therefore, the first and second gear members 60, 70 become coupled with the clutch bearing 130, 140, respectively. If the user manipulates the pedals 20 in the counterclockwise direction as shown by an arrow of Fig. 5, the clutch bearings 91, 92 which are connected to the pedals 20 via the shaft 22 also rotates backward. Since the balls 91c are closed between the slanted surfaces 91b of the clutch bearing 91 and the first gear member 60 and the balls 92c are also closed in relatively narrow spaces between the opposite slanted surfaces 92b of the clutch bearing 92 and the second gear member 70. Therefore, the balls 91c may move toward wide slanted surface 91b and the first gear member 60 is fixed forward and rotatable backward. On the other hand, the second gear member 70 is fixed backward and rotatable forward by the clutch bearing 92. In the meantime, the planetary gears 74 movably mounted to the second gear member 70 are engaged with the inner gear 62 of the first gear member 60, so that the planetary gears 74 rotate but not race. Therefore, when the pedals 20 are stepped by the user for backward traveling, the latch member 85 and the clutch bearing 91 rotates backward being coupled with the first gear member 60, so that the planetary gears 74 supported by the pins 75 rotates and the pinion 50 which is engaged among the planetary gears 74 rotates normally in the forward direction, thereby transmitting the driving power to the rear wheels via the chain 31 in the 16 opposite direction to the rotation of the pedals 20. At this time, the rotation ratio is accelerated. EFFECT OF THE INVENTION According to the present invention as described hereinabove, if the user simply manipulates the operation lever, the bicycle may run forward regardless of the forward rotation and the backward rotation of the pedals, so that the user may develop their leg-muscles in balance and feel little bored and tired while riding the bicycle as well as accelerating the running speed selectively. Furthermore, according to the present invention, any additional change gear is not necessary any more and the users may obtain a bicycle at a relatively low cost. Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as described in the accompanying claims.

Claims: 17 WHAT IS CLAIMED IS: 1. A traveling and accelerating system for bicycles comprising: a frame having a front wheel at a front part and a rear wheel at a rear part thereof; a pair of pedals fixed at both sides of a shaft which is rotatably supported at a boss being fixed under a center of the frame, to be driven by a user's feet; a driving sprocket axially fixed on the shaft for transmitting rotation power via a chain to the rear wheel; a housing attached at one side of the boss to be closed with a cap and having a hollow cross-sectional shape to accommodate accessories; a pinion axially fixed on the shaft beside the driving sprocket in the housing; a first gear member accommodated in the housing and having an inner gear part along its inner diameter; a second gear member movably contacted the first gear member and provided with planetary gears to be engaged with the inner gear part of the first gear, the planetary gears being fixed by pins and rotatable with relation to the pins; latch means respectively inserted in the first gear member and the second gear member for rotate them respectively in one direction; and a conversion control part connected to a release cable outside the housing for setting a travel mode or an acceleration mode corresponding to rotation directions of pedals by controlling engagement of the first gear member 18 and the second gear member according to the user's selection. 2. The traveling and accelerating system for bicycles according to claim 1, wherein the latch means comprises a plurality of grooves formed in a predetermined interval and the grooves have slanted surfaces in different directions, so that a pair of clutch bearings having balls and springs is assembled in inner diameters of the first second gear means. 3. The traveling and accelerating system for bicycles according to claim 1, wherein the conversion control part includes clutch bearings to be coupled to the first gear member and the second gear member for controlling them when the first and second gear means rotate in an opposite direction, and the clutch bearings control the rotations of the first gear member and the second gear member according to positions of clutch pins of moving plates which move in response to change of lever position. 4. The traveling and accelerating system for bicycles according to claim 3, wherein the lever of the conversion control part is elastically mounted by a spring and controlled its position according to manipulation of a user by means of a release cable in such a manner that protrusions on the moving plates become inserted into grooves of the lever. 5. The traveling and accelerating system for bicycles according to claim 3, wherein the clutch 19 bearings are formed with a plurality of slanted grooves to accommodate balls and springs.

Inventors: LEE YUN-RAK, PARK JONG-IL, LEE, YUN-RAK, PARK, JONG-IL
Applicants: LEE YUN RAK, PARK JONG IL, LEE, YUN-RAK, PARK, JONG-IL
Application year: 1999
Main classification: B62M11
IPC codes: B62M1, B62M11