EP0865375A1

EP0865375A1 - Apparatus for changing power direction for bicycle

Info

Publication number: EP0865375A1
Application number: EP96940729A
Authority: EP
Inventors: Moon-Soo Samick Apartment YOO (2nd)
Original assignee: World Industry Co Ltd
Current assignee: World Industry Co Ltd
Priority date: 1995-12-08
Filing date: 1996-12-06
Publication date: 1998-09-23
Also published as: RU2156204C2; KR19990071896A; CA2237112A1; TW385288B; JPH11500981A; JP2969378B2; WO1997021587A1; BR9611869A; KR970042078A; AU1072297A

Abstract

An apparatus for changing power direction for a bicycle is provided. The apparatus for changing power direction roughly including a shaft housing (30), a change ring (40), a carrier (50), a sun gear (60) and a sprocket cap (70) is located between a pedal shaft (20) and a driving sprocket. The shaft housing (30) supports the rotating pedal shaft (20) and controls the carrier (50) by using a plurality of pawls (32) to be released from and inserted into a plurality of openings (31) formed at the inside of a rim of a right cap of the shaft housing (30) when pedaling rearward. The change ring (40) releases and inserts the pawls (32) from and into the shaft housing (30) when pedaling rearward, and the carrier (50) having a first ratchet (51) and a second ratchet (52) at the outside and inside of a left portion thereof, repectively, and a plurality of planetary gears (54) to be rotatably set at a right portion maintains or changes the direction of power from the pedal shaft (20), thereby transmitting the power to a driving sprocket.

Description

APPARATUS FOR CHANGING POWER DIRECTION FOR BICYCLE

Technical Field

The present invention relates to an apparatus for changing power direction for a bicycle, and more particularly, to an apparatus for changing power direction attached to a pedal shaft hub for a bicycle in which the bicycle can travel forward at all times by controlling a changing lever when pedaling the bicycle forward or rearward, and an idling is also allowed if required when pedaling the bicycle rearward, like when pedaling a conventional bicycle rearward

Background Art

Generally, a bicycle includes front and rear wheels befoie and after a bicycle frame, and a pan ot pedals as a power supply source between two wheels The driving force tor bicycle is obtained through pedaling and then the force is transmitted to the rear wheel via a driving sprocket, a chain and a driven sprocket This general bicycle travels forward when pedaling forward by a πdei and the rear wheel of the bicycle rotates without load by an one-directional ratchet ot a hub of the rear wheel when pedaling rearward, wherein the rotation of the rear wheel without load is called "idling" . Also, inventions for new parts of bicycle which can allow of bi-directional pedaling to the general bicycle to which only one-directional pedaling is allowed have been disclosed Particularly, those of Mantzoursos et al. and Foster et al will be introduced as follows

According to the invention of Mantzoutsos et al. (EPO Publication No 0,369,925), two gears are installed on a pedal shatt and an auxiliary gear is installed between two gears to be detachable Here, the bicycle of this invention can travel like a general bicycle when pedaling in the state where the auxiliary gear is detached However, the bicycle can travel forward through the change of rotation direction of the pedal shaft by the auxiliary gear when pedaling rearward while the auxiliary gear is attached

On the other hand, according to the invention of Forster et al (US Patent No. 5,435,583). a gear box is installed on a pedal shaft, including two gears, two clutches therebetween and a bevel gear between two gears' teeth. Here, the bicycle of this invention can travel like a general bicycle when pedaling while the clutch is coupled with the right gear. However, the bicycle can travel forward through the change of the rotation direction of the pedal shaft by the bevel gear when pedaling rearward while the clutch is coupled with the left gear.

The above two inventions are meaningful in the aspect of the bi-directional pedaling apparatus which can drive the bicycle forward by adopting a mid gear when pedaling rearward. However, life span of the bi-directional pedaling apparatus is shortened due to abrasion of a specific ponion to which a force required for changing the power direction is applied and there is inconvenience in the operation of the apparatus for changing power direction..

A bi-directional pedaling apparatus obtained by solving the above defects is disclosed in Korean Patent Application No. 94-13391 . According to this application, a predetermined closed space is formed between one end of a pedal shaft and a driving sprocket, and two one-directional ratchets are installed at the outer and inner portions of the space. Also, a ratchet wheel to which a plurality planetary gears are rotatably set, and a changing lever for controlling the locking and unlocking of the outer one-directional ratchet are provided in the closed space. The bi-directional pedaling mechanism of the bicycle in the bi-directional pedaling apparatus is as follows.

When pedaling forward, the pedal, the ratchet wheel and the driving sprocket integrally rotate to travel the bicycle forward. Meanwhile, the outer one- directional ratchet instead of the inner one-directional ratchet functions by the changing lever when pedaling rearward. Here, there are two cases where the outer ratchet is locked and unlocked. First, when pedaling rearward while the outer ratchet is locked, the plurality of planetary gears rotate around own shafts thereof, so that the rotation direction of the pedal shaft is changed and then power from the pedal shaft is transmitted to the driving sprocket, thereby driving the bicycle forward. Second, when pedaling rearward while the outer ratchet is unlocked, the planetary gears rotate and simultaneously revolve around the pedal shaft in cooperation with the ratchet wheel. As a result, power from the pedal shaft cannot be transmitted to the driving sprocket, resulting in the idling of the pedal. According to the above-described Korean Patent Application No 94-13391 , the concentration of force on a specific portion by the changing of power direction is prevented by dispersing the force using the plurality of planetary gears Thus, life span of the bi-directional pedaling apparatus is prolonged and the rotation direction of the pedal shatt can be simply changed by using the changing lever Also, the bi-directional pedaling apparatus can operate actively by adopting small and precise parts

However, in the above-described Korean Patent Application No 94- 13391 , mass production of the parts and assembling of each part are difficult and the bi- directional pedaling apparatus cannot be attached directly to a conventional bicycle so that the parts thereof should be improved partiallv Also, each constituent pan mav be broken b) a eι se-load caused when pulling back the bicvcle

Disclosure of the Invention As an improved invention from the Korean Patent Application No 94

13391 , it is an object of the present invention to provide an apparatus toi changing power direction for a bicycle which can be produced on a large scale by improving the shape of each constituent part to be suitable for the simple manufacture and assembling of the parts, which can be directly attached to a conventional bicycle by improving parts and adopting an auxiliary means, and simultaneously which can prevent the damage ot parts caused by a reverse-load

The apparatus tor changing power direction of the present inv ention includes basic constituent elements for the bicycle, such as a pedal shaft, a rear wheel, a driving sprocket rotating with being formed on the pedal shaft a driven sprocket for transmitting the driving force of the driving sprocket to the rear wheel, and a chain connecting the driving sprocket and the driven sprocket I he basic characteristic of the present invention is the "apparatus for changing powei direction' tormed in a closed space between the pedal shaft and the driving sprocket Here, the shape of parts used for constituting the apparatus for changing power direction is a hollow cylindrical, ring- or gear-type

The apparatus for changing power direction ot the present invention located between the pedal shaft and the driving sprocket roughly includes a shaft housing. a change ring, a carrier, a sun gear and a sprocket cap The functions of each constituents are as follows

The shaft housing receiving the change ring, the carrier and the sun gear supports the rotating pedal shaft and simultaneously controls the carrier by using a plurality of pawls to be released from and inserted into a plurahty of openings formed at the inside of a nm of a right cap of the shaft housing when pedaling rearward The change ring releases and inserts the pawls from and into the shaft housing when pedaling rearward, and the carrier having ratchets at the outside and inside of a left ponion thereof, respectivel) , and a plurality of planetary gears to be rotatably set at a right portion maintains or changes the direction of power from the pedal shaft, thereby transmitting the po ei to a driving spiocket T he sun gear transmits the driving force of the pedal shalt to the carrier while being coupled with the pedal shaft Also, the sprocket cap having a gear at the right of the inside of the rim thereoi receives the power from the carrier to travel the bιc\ cle forward at all times regardless of forward and backward pedaling directions

Thereiore, the bicycle travels forwaid when pedaling forward and rearward in the state wheie the apparatus foi changing power direction is installed to the bicycle The apparatus for changing power direction oi the present invention as one of "bi-directional pedaling apparatus' is different from the conventional bi- directional pedaling apparatus in the constituent parts and operating mechanism In addition, according to the apparatus tot changing power direction of the present invention, the shapes of each coαstituent elements aie optimized, preventing the concentration of load on a specific portion Also, all constituent parts are integrally formed, thereby simplifying the assembling process thereof The apparatus for changing power direction adopts a changing levei so as to easily operate the same, and an auxiliary ring which is for installing the apparatus for changing power direction to the conventional bicycle without the modification of the conventional bicycle

Brief Description of the Drawings

FIG 1 is a cross-sectional view ot an apparatus tor changing power direction tor a bicycle according to the present invention, FIG 2 is an exploded perspective view of the apparatus for changing power direction according to the present invention,

FIG 3 is a right side view showing an example of a sun gear adopted in the apparatus for changing power direction according to the present invention, FIG 4A is an operational diagram of the apparatus for changing power direction, cut along line A-A of FIG 1 , when a change ring allows the release of the first pawls from the openings of the shaft housing, and FIG 4B is an operational diagram of the apparatus for changing power direction, cut along line A-A of FIG 1 , when the change ring blocks the release of the first pawls from the openings of the shaft housing,

FIG 5 is a cross-sectional view of the apparatus foi changing powei direction cut along line B-B ol FIG 1

TIG 6 is a cross-sectional view of the appai atus for changing powei direction according to a preferred embodiment of the present invention FIG 7 is a right side view of a shaft housing adopted in the apparatus for changing power direction shown in MG 6,

FIG 8 is a left side view of a carrier adopted in the apparatus for changing power direction shown in FIG 6,

FIG 9 is a left side view of a sprocket cap adopted in the apparatus foi changing power direction shown in FIG 6,

FIG 10 is a πght side view of a means for controlling a change ring according to another embodiment ot the piesent invention, and

FIG 11 is a cross-sectional view when the apparatus for changing power direction is installed to a conventional bicycle according to still another embodiment of the present invention

Best mode tor carrying out the Invention

The present invention will be descπbed in detail w ith reference to FIGS 1 to 5 As shown in FIGS 1 and 2. a shaft housing 30. a change ring 40 a carrier

50 and a sun gear 60 and a sprocket cap 70 are coupled in sequence on a pedal shaft 20 of a bicycle to form an integiated apparatus for changing power direction by attaching a fixing nut 90 to the outside of the sprocket cap 70 The structures of each pan and functions thereof will be described in sequence

The shaft housing 30 supports the rotating pedal shaft 20, and has a plurality of openings 31 at the inside of a rim of a right cap of the shaft housing 30, into which a plurality of first pawls 32 are inserted Also, a hole 33 to which a first gear 81 for controlhng the change ring 40 is fitted is formed at the sidewall of the right cap The shaft housing 30 having the above structure holds the change ring 40, the carrier 50 and the sun gear 60 in sequence and simultaneously has a function of rotating the carrier 50 or preventing the rotation of the carrier 50 by using the first pawls 32 placed at the nm of the shaft housing 30 when pedaling backward Here a spπng is inserted between the shaft housing and the fust pawls 32 to elastically holding the first pawls 32 in the openings 31

T he change πng 40 has a second gear 41 at one side thereof tow ard the pedal shatt and a plurality of holes 42 at the surface portion thereof The second gear 41 is in mesh with the first gear 81 to rotate the change ring 40 and the holes 42 is for permitting projection or shrink ot the first pawls 32 The carrier 50 cannot rotate when the first pawls 32 are slid into the holes 42, and the carrier 50 can rotate when the change πng 40 blocks the fu st pawls 32 within the openings 31 of the shaft housing 30 The carrier 50. having a hollow cylindrical shape, has a first ratchet 51 and a second ratchet 52 at the outside and inside of a left portion, respectively and a ring 53 having a plurahty of holes at a right portion of the carrier 50 wherein the right portion is integrally coupled with the left portion such that a plurality of planetary gears 54 are rotatably set by a planetary gear shaft 55 m the ring 53 The first ratchet 51 ot the carrier 50 having the above structure is engaged with the first pawls 32 of the shaft housing 30 and the second ratchet 52 is engaged with second pawls 62 of a sun gear 61 which will be explained later On the other hand, an inner portion of the planetary gears 54 of the carrier 50 is engaged v\ ιth a third gear 61 of the sun gear 60 and an outer portion thereof is engaged with a fourth gear 71 formed at the mside of the sprocket cap 70 which will be explained later

The carrier 50 has a function of transmitting the power from the pedal shaft 20 to the sprocket cap 70 by maintaining or changing the direction of power from the pedal shaft 20, which is the most important in the present invention. The planetary gears 54 of the carrier 50 disperses the force concentrated on a specific portion by the change of the power direction and preferably, the number of planetary gears is eight.

The sun gear 60, having a hollow cylindrical shape with steps, a left portion with smaller diameter of the sun gear 60 has a plurality of openings 63 at the outside thereof, to which the second pawls 62 are set, and the inside of the left portion has a central opening having a hexagonal and spline-like shape such that the left portion is integrally fixed to the pedal shaft 20 Also, a right portion with larger diameter of the sun gear 60 has the third gear 61 at the outside thereof In the sun gear 60 having the above structure, tlie second pawls 62 are engaged with the second ratchet 52 of the carrier 50 and the third gear 61 is engaged with the planetar) gears 54 of the carrier 50 Here, the numbei of the second pawls is preferably four

Here, elasticity can be provided to the first and second pawls 32 and 62 bv the following methods. First, a coil or leaf spring is inserted beneath the pawls Second , a flute is formed at each pawl with a predetermined angle as shown in FIG 3 and then each pawl is connected by an annular spring 65 to provide a hneai tension

Also, according to the present invention, the first pawls 32 and the change ring 40 locate at the outside of the carrier 50 to control the carrier 50 only when the pedal shaft 20 rotates reversely Also, the second pawls 62 locate at the outside of the sun gear 60 to allow one-directional rotation to the carrier 50 in the forward rotation

Since the sun gear 60 is integrally coupled with the pedal shaft 20, the sun gear 60 transmits the power from the pedal shatt 20 to the carrier 50 while rotating in the same direction as the rotation direction of the pedal shaft 20.

The sprocket cap 70 has the fourth gear 71 at the right of FIG. 1 of the inside of the rim thereof, and a plurahty of screws or brackets 72 at the outside of the rim. such that driving sprockets 73 having multiples steps is coupled thereto Also, a bearing 74 is fixed at the center of the sprocket cap 70. so that the sprocket cap 70 can freely rotate independent on the pedal shaft 20. The fourth gear 71 of the sprocket cap 70 having the above structure is engaged with the planetary gears 54, thereby receiving power from the pedal shaft 20 via the carrier 50

The sprocket cap 70 rotates forward at all times regardless of the rotation direction of the pedal shaft 20

Also, reference numerals 10, 1 1 , 21 and 23 in FIG 1 which are not explained above represent a bicycle frame, a pedal shaft hub, a shaft bearing and a washer, respectively

When coupling the shaft housing 30 with the sprocket cap 70 on the pedal shaft 20 of the bicycle, a closed space is formed therebetween, and the change ring 40. the carrier 50 and the sun gear 60 are assembled being engaged each other in the space and a fixing nut 90 is fixed to the outside of the sprocket cap 70 therein forming an integrated apparatus foi changing power direction

The integrated powei changing apparatus is assembled by the following sequence First, the pedal shatt 20 is rotatably set in the shaft housing 30, and then the change ring 40, the carrier 50, the sun gear 60 and the sprocket cap 70 are assembled in sequence centering the pedal shatt 20 within the shatt housing 30 Then, the fixing nut 90 is fixed to the outside of the sprocket cap 70, thereby resulting in an integrated apparatus for changing power direction Also, a changing lever 80 for controlling the change ring 40 is set at the sidewall of the shaft housing 30 and connected to the first gear 81 Thus, the changing lever 80 moves the change ring 40 using the motion of the first gear 81

The operation and effect of the apparatus for changing power direction according to the present mvention having the above structure will be descπbed below

For convenience^" sake in description, the operation of the present invention will be descπbed by classifying the operational method into "'forward traveling b\ foi ward pedaling" , "forwaid traveling by rearward pedaling" , and " idling by learward pedaling^" First, "forward traveling by forward pedaling^" means that the bicycle travels forward when driving pedal shaft 20 clockwise (this direction is referred based on the case where the bicycle is viewed from the πght with respect to the travehng direction of the bicycle, which is also applied to the following description) as shown in FIGS 4 and 5 Here, the power from the pedal shaft 20 is transmitted as follows

When driving the pedal shaft 20 clockwise, the sun gear 60 rotates clockwise in cooperation with the pedal shaft 20 Here, since the second pawls 62 are engaged with the second latch 52, the carrier 50 rotates in the same direction as the pedal shaft 20 Accordingly, the planetary gears 54 do not rotate for themselves while the fourth gear 71 of the sprocket cap 70 which are engaged with the planetary gears 54 rotates clockwise Thus, the pedal shaft 20 and the sprocket cap 70 rotate in the same direction each other, thereby traveling the bicycle forward

Second forward traveling bv l earward pedaling means that the bicycle travels forward w hen driving pedal shaft 20 counterclockw ise Heie. the powei from the pedal shatt 20 is transmitted as follows Por this opei ation, the first pawls 32 and the first ratchet 51 should be engaged each other b> controlling the change ring 40 as shown in FIG 4A

When driving the pedal shaft 20 counterclockwise, the sun gear 60 rotates counterclockwise in cooperation with the pedal shaft 20 Here since the second pawls 62 is slid over the second latch 52, it is impossible to transmit power to the carrier 50 Meanwhile, as shown in FIG 5, the third gear 61 of the sun gear 60 transmits power to the planetary gears 54 which are engaged with the sun gear 60 thereby rotating the planetary gears 54 clockwise Here the i otation of the planetary gears 54 provides a force for rotating the carrier 50 which is integrally coupled with the planetary gears 54 However, the carrier 50 cannot rotate counterclockwise since the first pawls 32 are engaged with the first ratchet 51 of the carrier 50 as shown in FIG 4 A Thus, the sprocket cap 70 engaged with the planetary gears 54 rotates clockwise while only the planetary gears 54 rotate as shown in FIG 5 By this operation duection of the driving toice applied to the pedal shaft 20 in the counterclockwise is changed via the apparatus for changing power direction ot the present invention, thereby rotating the sprocket cap 70 clockwise

T hird " idling by rearward pedaling^" means that the bicycle cannot travel since the power is not transmitted to the sprocket cap 70 while only idling occurs when driving pedal shaft 20 counterclockwise Here, the power from the pedal shaft 20 is transmitted as follows For this operation, the first pawls 32 of the shaft housing 30 and the first ratchet 51 of the carrier 50 should not be engaged each other by controlling the change ring 40 as shown in FIG 4B

Here, the power transmit process for the above operation is the same as those of "forward traveling by rearward pedaling" to the step where counterclockwise force is apphed to the carrier 50 by the planetary gears 54, except that the carrier 50 itself revolves around the pedal shaft 20 counterclockwise while the planetary gears 54 rotate since the first pawls 32 are not engaged with the f irst ratchet 51 Thus, power f rom the pedal shaft 20 is transmitted only to the cai πer 50 not to the sprocket cap 70. so that the bicvcle cannot travel

I he idling by rearward pedaling in the general bicycle is different f rom the " idling by rearwaid pedaling" by the apparatus foi changing power direction of the present invention in the following aspects That is, in the idling by learward pedaling in the general bicycle, the driving sprocket and the chain reverse]} rotate in cooperation with the pedal shaft However, the driving sprocket and the chain do not rotate in the present invention

As described above, the apparatus of the present invention as one of "bi- directional forward traveling apparatus" transmits power in the different manner from the conventional apparatus by adopting new parts Also, since the shape of each constituent part is optimized, concentration of load on a specific portion is prevented Also, each part is integrated, so that the assembling can be performed simply In addition, a lever is attached to simplify the operation of the apparatus and the structure of the shatt housing is modified to be directly attachable to the conventional bicycle, which will be explained in the following embodiments of the present invention

Hereinafter, the first, second and third embodiments of the present invention will be described based on the above present invention In the first embodiment, the locations of an one-directional ratchet used tor the forward rotation and a ratchet foi controlling the reveise rotation are shifted each other In the second embodiment, the changing lever is replaced by a wire Also in the thud embodiment, the shape of the shaft housing is modified such that the apparatus for changing power direction can be attached directly without modification of the conventional bicycle

< Embodiment 1 >

Referring to FIGS 6 to 9, a basic characteristic of this embodiment is to change the locations of an one-directional ratchet used for the forward rotation and a ratchet for controlling the reverse rotation That is, the location of the ratchet used for the forward rotation is shifted from the inside of the can ier to the outside thereof while the location of the ratchet used for controlling the reverse rotation is shifted viceversa

For shifting the locations of the abov e tw o ratchets, each constituent part is manufactured with different shape fi om the above-described present invention However, the number of parts are the same as the above present invention and the operation thereof is similar to the above present invention The shape of the modified parts will be described as follows

As shown in FIGS 6 and 7 a shaft housing 130 has a hollow cylindrical protrusion at the right thereof and a plui aht} ot openings 131 at the outside thereof, into which a plurality of third pawls 132 aie inserted The shatt housing 130 has a circular plate type sidewall and a hole 133 for receiving the first gear 81 of the above present invention at a position hich is near the pedal shatt 120 compared with the hole 33 of the above present invention since the shaft housing 130 is obtained by removing the nm of the shaft housing 30

A change ring 140 of this embodiment is different from the change ring 40 of the above piesent invention in the aspect in that a fifth gear 141 is formed at one side thereof toward the outside of the pedal shaft 120 The change ring 140 locates between the third pawls 132 and the third ratchet 151 of the carπei 150

As shown in FIGS 6 and 8 a u πei 150 of this embodiment has a pluiaht} of opening 153 into which a plurahty of fourth pawls 152 are inserted at the outside of a left portion of the carrier 150 and a third ratchet 151 at the inside of the left portion Also a πght portion of the carrier 150 is the same as that of the carrier 50 of the above present invention In the carrier 150 having the above structure the fourth pawls 152 are engaged with a fourth latch 172 of a sprocket cap 170 and the third ratchet 151 is engaged with the third pawls 132 of the shaft housing 130 A sun gear 160 of this embodiment has an inside fixed to the pedal shaft 160 and an outside having a sixth gear 161 which is engaged only with a plurality of planetary gears 154

Also, as shown in FIGS 6 and 9. the sprocket cap 170 has a seventh gear 171 at the right of FIG 6 of the inside ot the nm and a fourth ratchet 172 at the left thereof Thus, the seventh gear 171 is engaged with the planetary gears 154 of the carπei 150 and the fourth ratchet 172 is engaged with the fourth pawls 152 ot the carπei 150

The other parts arc the same as those ot the above present invention Also, in FIGS 6 to 9, reference numeral 1 10 repiesents a bicycle frame l eteience numei al 1 1 1 represents a pedal shaft hub, reference numeral 153 iepresents a carrier ring, reference numeral 155 represents a shaft of the planetar) geai s and leference numeral 173 represents a sprocket bracket

The operation and effect of this embodiment having the above structuie will be described below

First the "forward traveling by forward pedaling" is performed b} the following mechanism When the pedal shaft 120 rotates clockwise, the sun gear 160 rotates in the same direction as the pedal shaft 120 and the planetary gears 154 rotates counterclockwise However, the carrier 150 itself rotates clockwise in a different rotating rate from that of the pedal shaft 120 and the fourth pawls 152 of the carrier 150 is engaged with the fourth ratchet 172 of the sprocket cap 170, thereby rotating the sprocket cap 170 clockwise Next, the "forward traveling by rearward pedaling" is performed when the third pawls 132 of the shaft housing 130 are engaged with the third ratchet 151 of the carrier 150 after the change πng 140 allows the release of the third paw ls 132 from the holes of the change ring 140 That is. the forward traveling by learward pedaling is performed while the carπei 150 is fixed Thus, the planetary gears 154 change the direction of power from the sun gear 160 while rotating around then own shafts, thereby providing the power to the sprocket cap 170 clockwise

Finally, the "idling by learward pedaling^' is performed by the following mechanism The change ring 140 blocks the release of the third pawls 132 from the openings of the shaft housing, so that the carrier 150 rotates in the same direction as the pedal shaft 120 As a result, the power from the sun gear 160 cannot be transmitted to the sprocket cap 170

< Embodiment 2 >

The second embodiment of the present invention relates to the controlling of the change ring 40

The change ring 40 of the above present invention releases and blocks the first pawls 32 bv using the first gear 81 (see FIGS 1 and 2) formed at the sidewall of the shaft housing 30 In order to control the first gear 81 formed in the shaft housing 30, the shaft housing 30 should be drilled to form a hole 33 thiough w hich the changing levei 80 is installed from the outside When rotating the changing lever 80 in the fiont and back, the first gear 81 lotates in cooperation with the changing lever 80 and the change ring 40 engaged with the first gear 81 rotates in the same direction as the changing lever 80. theieby ieleasing and blocking the first pawls 32

The above changing lever 80 is protruded to the outside of the shaft housing 30, so that the protruded changing lever 80 prevents the successful coupling of the apparatus for changing power direction to the conventional bicycle

Thus, the second embodiment is to improve the above defect Here a steel wire is adopted instead of the changing lever to easily connect the apparatus for changing power direction to the conventional bicycle, thereby controlling the change ring As shown in FIG 10, a means for controlling a change πng 43 of the second embodiment has a loop 44 at one end of the change πng 43 having a plurality of holes 45 Here, the loop 44 is for connecting a steel wire 46 fiom the outside of the shatt housing 30 via a hole 33. thereby controlhng the change ring 43 That is, the change ring 43 blocks the first pawls 32 when the steel wire is pulled, and the change ring 43 releases the first pawls 32 when the steel wire 46 is pushed < Embodiment 3 >

The third embodiment relates to the shaft housing 30, wherem the shape of the shaft housing 30 is modified to a shaped which is suitable for directly attaching the apparatus for changing power direction of the present invention to the conventional bicycle without the modification of the conventional bicycle

FIG 1 1 shows the state where the apparatus for changing power direction of the present invention is installed to the conventional bicycle In the third embodiment, appearance of the shaft housing 30 having a hollow cylindrical shape is improved A shaft housing 34 of this embodiment has a multiple-stepped appearance

That is, the cylindrical shaft housing 34 is multiple-stepped to the left sequence, wherein the diametei of the left side is smallei than that of the right side of the shaft housing 34 iso a connection tube 1 5 is adopted to pro ide compatibiht} when connecting the apparatus for changing powet direction to the pedal hub 1 1 of the conventional bicycle A right-handed screw 35 is formed at the outside of the connection tube 15 Also, the outei diametei ot the connection tube 35 is the same as that of the pedal hub 1 1 and the innei diametei thereof is the same as the outer diameter ot the shaft housing 34 On the other hand, an additional nut 36 is manufactured as follows A left-handed screw 37 is formed at the outside of the nut 36 and a left inside of the nut 36 is processed to have a taper 38

Accordingly, the shaft housing 34 is installed to the conventional bicycle by the following procedures First, the connection tube is coupled with the pedal hub 11 using the right-handed screw 35 and the connection tube 15 is coupled with the shaft housing 34 through a spline coupling Then, the nut 36 is screwed at the opposite side through left-handed screw coupling by the left-handed screw 37 and then the assembling is completed using a washer 39

When connecting the apparatus foi changing power direction of this embodiment to the conventional bicycle the shaft housing 34 is much tightl} connected to the pedal hub 1 1 even though a reveise load caused by the pulling back of the bicycle is applied to the apparatus foi changing power direction of the present invention via the driving sprocket That is, as the reverse load applied to the apparatus for changing power direction increases, the shaft housing 34 is much tightly connected to the pedal hub 11 by the taper 38 formed at the inside of the nut 36 since the right-handed screw 35 of the connection tube 15 and the left-handed screw 37 of the nut 36 are coupled in the opposite direction each other

Also, the shaft housing 30 and the pedal hub 11 may be tightly coupled each other by processing a contact portion between the sides of the shaft housing 30 and the pedal hub 11 to have a ridge and valley-type

Industrial Applicability

Therefore, the bicycle travels forward when pedaling forward and rearward in the state where the apparatus for changing power direction is installed to the bicycle Also, an idling may occur if lequired when pedaling rearward in the state wheie the apparatus for changing power direction is installed to the bicycle I he apparatus for changing power direction of the present invention as one ot "hi directional pedaling apparatus" is different from the conventional bi-directional pedaling apparatus in the constituent parts and operating mechanism In addition according to the apparatus for changing power direction of the present invention the shapes of each constituent elements are optimized thereby preventing the concentration of load on a specific portion Also, all constituent parts are integrall} formed, thereby simplifying the assembling process thereof The apparatus for changing power direction adopts a changing lever so as to easily operate the same, and an auxiliary ring which is for installing the apparatus for changing powei direction to the conventional bicycle without the modification of the conventional bicycle

Claims

What is claimed is

1 An apparatus for changing power direction for a bicycle as a bi¬ directional pedaling apparatus including a sun gear coupled with a pedal shaft, a carrier to which a plurality of planetary gears are rotatably fixed, and a driving sprocket with an internal gear, said apparatus for changing power direction comprising a shaft housing for supporting a rotating pedal shaft, having at least one oi more openings at the inside of a nm of a right cap of said shaft housing and a hole at the sidewall thereof, wherein a plurality of fu st pawls are inserted into said openings and a means for controlling a change ring is inserted into said hole and said first pawls are engaged with a first ratchet of a carrier, a change ring positioned between said shaf t housing and a first i atchet of a carπei having a second geai at one side thereof tow ard said pedal shatt with being coupled with said means for controlling said change ring and at least one or more holes at the surface portion thereof for permitting projection or shrink of said first pawls, a carrier with a hollow cylindrical shape, having a first ratchet and a second ratchet at the outside and inside of a left portion thereof respectively , and a ring having at least one or more holes at a right portion thereof, wherein the right portion is integrally coupled with the left portion such that at least one or more planetary gears are rotatably set by a planetary gear shaft, and said second ratchet is engaged with second pawls of a sun gear, and an innei portion of said planetary gears is engaged with a third gear of a sun gear and an outer portion thereof is engaged with a fourth gear formed at the inside of a sprocket cap, a sun gear with a hollow cylindrical shape with steps, having at least one or more openings at the outside of a left portion theieof with smaller diameter wherein said second pawls are connect into said openings and a center opening to be coupled with said pedal shatt at the inside of the left portion, and a third gear at the outside of a right portion with larger diametei . and a sprocket cap, having a fourth gear at the nght ot the inside of the nm thereof wherein said sprocket cap freely rotates independent on said pedal shaft and is fixed to said pedal shaft by a fixing nut 2 An apparatus for changing power direction for a bicycle as claimed in claim 1 , wherein eight first pawls are located on said openings of said shaft housing

3 An apparatus for changing power direction for a bicycle as claimed in claim 1 , wherein said means for controlling said change ring is a first gear

4 An apparatus for changing power direction for a bicycle as claimed in claim 3. wherein said first gear is controlled by installing a changing lever at the outside of said shaft housing

5 An apparatus for changing power direction for a bicycle as claimed in claim 3 wherein said means for controlling said change ring of said shaft housing controls a change πng using a steel wne, wherein a loop is formed at one end of said change nng and said steel wire is inserted f rom the outside to said loop via a hole of said shatt housing

6 An apparatus tor changing power direction for a bicycle as claimed in claim 1 , wherein the number of said holes of said change ring is eight

7 An apparatus for changing power direction for a bicycle as claimed in claim 1 , wherein the number of said planetary gears of said carrier is eight

8 An apparatus for changing powei direction for a bicycle as claimed in claim 1. wherein four second pawls are inserted into said openings of said sun gear 9 An apparatus for changing power direction for a bicycle as claimed in claim 2 or 8, wherein a spring device is inserted between said openings and said pawls

10 An apparatus for changing power direction for a bicycle as claimed in claim 9. wherein said spring device is one circular spring for connecting flutes of pawls

11 An apparatus for changing powei direction for a bicycle as claimed in claim 1 , wherein said sun gear has a center opening with a hexagonal shape

12 An apparatus for changing power direction for a bicycle as claimed in claim 1 . wherein said sun gear has a center opening with a spline-like shape 13 An apparatus for changing power direction tor a bicycle as claimed in claim 1 , wherein said sprocket cap has a screw at the outside of a left portion ot the nm thereof and at least one or moie brackets at the outside of a right portion thereof such that one or more driving sprockets with multiple steps are coupled to said sprocket cap

14 An apparatus for changing power direction for a bicycle as claimed in claim 13, wherein a bearing is fixed to the center of said sprocket cap 15 An apparatus for changing power direction for a bicycle as a bi¬ directional pedaling apparatus including a sun gear coupled with a pedal shaft, a carrier to which a plurality ot planetary gears are rotatably fixed, and a driving sprocket with an internal gear, said apparatus for changing power direction comprising a shaft housing with a circular plate-type sidewall, for supporting a rotating pedal shah, having a hollow cylindrical protrusion at the right thereof , at least one or more thu d pawls at the outside thereof , and a hole for receiving a means foi controlling a change ring a change ring positioned between said third pawls and a thud ratchet of a carrier, having a fifth gear at one side thereof toward the outside ol said pedal shaft with being coupled with said means foi controlhng said change ring and at least one or more holes at the surface portion thereof, wherein said third pawls are controlled, a carrier, having at least one or more fourth pawls and said third ratchet at the outside and inside of a left portion thereof, respectively, and a πng with at least one or more holes at a right portion thereof, wherein the πght portion is integrally coupled with the left portion such that at least one or more planetary gears are rotatably set by a planetary gear shaft in said ring, and said lourth pawls is engaged with a fourth ratchet of a sprocket cap, and said third ratchet is engaged with said third pawls of said shaft housing, and an inner portion ot said planetary gears is engaged with a sixth gear of a sun gear, and an outer portion thereol is engaged with a seventh gear formed at the inside of a sprocket cap. a sun geai having an inside fixed to said pedal shaft and an outside with a sixth gear, and a sprocket cap, having a seventh gear at the inside of the nm thereof and a fourth ratchet at the outside thereof, wherein said sprocket cap freely rotates independent on said pedal shatt and is fixed to said pedal shaft by a f ixing nut 16 An apparatus tor changing power direction for a bicycle as claimed in claim 1 or 15. wherein said shaft housing is compatibly installed at the pedal hub of the bicycle by forming the outside of said shaft housing with multiple steps in the left in sequence and by using a connection tube with a right-handed screwed outside, having an outer diameter which is the same as the diameter of said pedal hub and an inner diameter which is the same as that of said shaft housing, and a nut having a left-handed screwed outside and a taper-processed left inside