TWI403431B - Power transmission apparatus for chainless bicycle - Google Patents

Abstract

The present invention relates to a power transmission device for a chainless bicycle, which uses a planetary gear device having multiple gear sets to achieve a variety of changes in gear ratio, and which enables easy gear-changing and reliable power transmission, and which enables the easy attachment and detachment of a rear wheel. To accomplish this, the power transmission device for a chainless bicycle according to one embodiment of the present invention comprises: a first gear change unit installed on a pedal shaft to increase the rotating speed of the pedal shaft and to output the increased rotating speed; a first bevel gear installed on the pedal shaft to rotate at the speed outputted by the first gear change unit; a power transmission shaft, on one end of which a second bevel gear which is to engage with a first bevel gear is arranged; a fourth bevel gear which is to engage with a third bevel gear arranged at the other end of the power transmission shaft; a second transmission unit which increases the rotating speed of the fourth bevel gear and outputs the increased rotating speed; and a rear wheel which rotates at the speed output by the second transmission unit. Both the first transmission unit and the second transmission unit have: a carrier connected to the pedal shaft and to the fourth bevel gear; a planetary gear group which has at least three support members protruding from a virtual circumference of one surface of the carrier, wherein at least three pairs of planetary gear groups are installed on the support members such that the three pairs of planetary gear groups are independently and freely rotatable, and wherein the planetary gear group consists of at least three planetary gears having different diameters; a ring gear group consisting of ring gears which are brought into internal contact and engagement with the respective planetary gears such that the ring gears are independently and freely rotatable; a sun gear group consisting of sun gears which are brought into external contact and engagement with the respective planetary gears, and which have different diameters and are formed into a unitary body; and gear change lock means for selectively locking either an output shaft or the ring gear connected to the sun gear group.

Description

Power transmission device for chainless bicycle

The present invention relates to a chainless bicycle, and more particularly to a power transmission device for a chainless bicycle, which is capable of achieving different gear ratios by a planetary gear device having a plurality of gear trains, and is convenient for speed. Changes, ensure power transmission, and facilitate connection/disassembly of the rear wheels.

Bicycles, which are a human-powered vehicle, have been used in various ways in areas such as transportation and recreational sports. Recently, bicycles have received attention as an environmentally-friendly transportation vehicle capable of actively coping with problems such as environmental pollution and rising oil prices. In addition, bicycles can be easily used by modern people who are obviously lacking in exercise.

In general, a bicycle has a structure in which power transmission is performed by connecting a pedal sprocket and a rear sprocket through a chain. The chain bicycle can realize different gear ratios by shifting the chain on the sprocket by using the pedal with the multi-stage structure and the rear sprocket, so that gear shifting can be realized.

However, conventional chain bicycles cause hygiene problems due to the user's clothes or body being contaminated with oil from the chain. In addition, the chain tends to deviate from the sprocket and may be damaged in the worst case. Therefore, security incidents occur frequently. The chain bicycle has a greater frictional loss due to the meshing between the chain and the sprocket, so the chain bicycle exhibits degraded power transmission efficiency and creates a lot of noise. Further, since the shifting of the bicycle is continuously realized during driving, the bicycle cannot be in a stationary state. Perform its shifting.

Therefore, chainless bicycles have been developed to provide efficient power transmission without the aforementioned chain. Typically, a chainless bicycle utilizing a helical gear has been developed. In the chainless bicycle using the helical gear, the power transmission shaft is used as a chain. In other words, the rotational force of the pedal shaft transmitted to the power transmission shaft by using the helical gear is orthogonally transformed. Thereafter, the rotational force of the power transmission shaft using the helical gear is orthogonally transformed, thus driving the rear wheel. When compared with the existing chain bicycle, the conventional chainless bicycle has a more simplified power transmission structure, and can exhibit better power transmission efficiency by reducing the friction between the helical gear and the power transmission shaft.

However, unlike a chain bicycle, a conventional chainless bicycle can neither easily achieve different gear ratios nor easily allow connection/disassembly of the rear wheels, so that replacement or repair of the rear wheels can be difficult. These problems have been cited as the biggest problem when promoting chainless bicycles.

It is an object of the present invention to provide a power transmission apparatus for a chainless bicycle that is capable of achieving different gear ratios in a more simplified configuration, facilitating speed changes, ensuring power transmission, and facilitating connection of rear wheels/ Disassembled.

These and other objects, features and advantages of the present invention will become apparent from

In order to accomplish the above object, a power transmission device for a chainless bicycle is provided. The power transmission device includes a first shifting unit Mounted on a pedal shaft and outputting power by increasing the rotational speed of the pedal shaft, a first helical gear train is mounted on the pedal shaft and rotated at a speed corresponding to the power of the first shifting unit, and a power transmission shaft system is disposed. A fourth helical gear is engaged with a third helical gear disposed at a side opposite to the power transmission shaft, and a second shifting unit is coupled to one end of the second helical gear that has a first helical gear. The power is output by increasing the speed of the fourth helical gear, and a rear axle is rotated at a speed corresponding to the power of the second shifting unit. The first shifting unit includes a first bracket system firmly coupled to the pedal shaft, the at least three first planetary gear sets are independently rotated from each other and assembled on at least three virtual circumferences on a surface of the first bracket a periphery of the protruding first support rod, wherein each of the first planetary gear sets includes at least three first planetary gears having diameters different from each other, and a first ring gear set includes the first planetary gears respectively a first ring gear internally meshed and independently rotating, a first sun gear set including first sun gears respectively meshing with the first planet gears and having diameters different from each other and integrated with each other, A first power output shaft is securely assembled into the first sun gear set, and a first locking unit selectively stops one of the first ring gears. The second shifting unit includes a second bracket system firmly coupled to the fourth helical gear, the at least three second planetary gear sets are independently rotatable from each other and assembled on at least three surfaces of the second bracket a virtual circumference around the second support rod, wherein each of the second planetary gear sets includes at least three first planetary gears having diameters different from each other, and a second ring gear set including the second and second a second ring gear that meshes internally and independently rotates from each other, and a second sun gear set includes externally meshing with the second planetary gears and having a different The diameters of each other and the second sun gear integrated with each other, a second power output shaft is firmly assembled into the second sun gear set, and a second locking unit selectively stops the second ring gears One.

According to the present invention, the first shifting unit and the first helical gear are mounted on a first housing supporting the pedal shaft, and the fourth helical gear and the second shifting unit are mounted on a second housing supporting a rear wheel axle. The power transmission shaft is mounted on a horizontal frame that connects the first housing and the second housing and has a tubular shape, and the first and second housings have first and second housing covers.

According to the present invention, in the first shifting unit, the first support rod supporting the planetary gear set and a pedal shaft connecting tube are formed on the surface of the first bracket, wherein the pedal shaft is firmly inserted into the pedal shaft connecting tube, the first sun The gear set is disposed on one side thereof having a power output shaft, wherein the pedal shaft connecting tube is assembled into the power output shaft and supported by the power output shaft, and a first power output shaft support plate is additionally provided, wherein the first power output The axle support plate is coupled with the first support bar to prevent the first sun, planet, and ring gear set from being disengaged from their position such that the first sun, planet, and ring gear set effectively mesh with each other and support the power take-off shaft, and first The helical gear is securely assembled around the power take-off shaft.

According to the invention, in the second shifting unit, the second support rod supporting the second planetary gear set is formed on the surface of the second bracket, and a fourth helical gear mount is formed on a pair of sides of the second bracket, A second power take-off shaft support plate is additionally provided, wherein the second power take-off shaft support plate is coupled with the second support rod to prevent the second sun, planet, and ring gear set from being disengaged from their position such that the second sun, planet, and The ring gear set effectively meshes with each other and supports the opposite side of the second output shaft, and has a tubular number The two power output shafts extend from the sun gear set such that the second power take-off shaft is assembled into the fourth helical gear mount and supported by the fourth helical gear mount.

According to the invention, in the first shifting unit, the first planetary gears are sequentially arranged from the first carriage in accordance with the order of their diameters. In the second shifting unit, the second planetary gears are sequentially arranged from the second bracket in accordance with the order of their diameters. The first sun gear has a ratio of 1:0.2 to 3 with the first planetary gear, and the second sun gear and the second planetary gear have a ratio of 1:0.2 to 3. Further, in the first ring gear set, the first ring gears have the same outer diameter as each other, and the plurality of first locking protrusions are equally spaced on an outer circumferential surface of each of the first ring gears. In the second ring gear set, the second ring gears have the same outer diameter as each other, and the plurality of second locking protrusions are equally spaced on an outer circumferential surface of each of the second ring gears.

According to the present invention, the first locking unit includes a first guiding groove formed along the first housing when the first brake is elastically receiving the support, and is formed by each of the first rings The first locking projection structure on the gear is selectively locked, a first system is formed on the first housing to enclose the movement track of the first brake and has a first openable cover, and a first wire tie Used to adjust a position of the first brake. The second locking unit includes a second brake that moves along a second guiding groove formed in the second housing when elastically receiving the support, and is formed by a second formed on each of the second ring gears The locking projection structure is selectively locked, a second system is formed on the second housing to surround the movement track of the second brake and has a second openable cover, and a second The wire is used to adjust a position of the second brake. The first cover further includes a first guide inserted into the first brake to guide the first brake to slidably move the first brake, and the second cover further includes a second guide inserted into the second brake The second brake is guided to cause the second brake to slidably move.

As described above, the chainless bicycle according to an embodiment of the present invention can realize different gear ratios by using the first and second shifting units of a planetary gear device having a plurality of gear trains.

Even if the chainless bicycle is in a stationary state, the chainless bicycle can perform the shifting. Because the chainless bicycle has a relatively simplified structure, the chainless bicycle can exhibit superior durability and ensure precise power transmission.

The rear wheels can be easily attached/detached from the chainless bicycle so that the rear wheels can be easily replaced or repaired.

Since the power transmission device for a chainless bicycle according to the present invention includes a battery for rotating the pedal shaft and an electric motor or an internal combustion engine, the chainless bicycle can be utilized as an electric bicycle or a motorized bicycle.

In the following, the preferred embodiments of the present invention will be described in detail with reference to the drawings, and the same reference numerals will be given to the same elements.

Hereinafter, the structure of a power transmission device for a chainless bicycle according to an embodiment of the present invention will be described with reference to the drawings.

1 is a perspective view showing a chainless bicycle 1 equipped with a power transmission device 2 according to an embodiment of the present invention. As shown in Figure 1, the root The power transmission device 2 according to an embodiment of the present invention changes the rotational speed of the pedal shaft 100 to drive the rear wheel 3. As shown in FIG. 1, the pedal 102 is connected to the pedal shaft 100 via the crossbar 101. When the pedal 102 is driven, the pedal shaft 100 of the power transmission device 2 is rotated. Differently, in order to rotate the pedal shaft 100, a battery (not shown), an electric motor (not shown) or a main engine (not shown) may be mounted on the bicycleless bicycle 1. In other words, the power transmission device 2 according to the present invention is suitable for an electric bicycle or a motorized bicycle. Motorized bicycle means a two-wheeled vehicle (eg, a motorized trailer or a quick-cart) that has an engine exhaust of 125 cubic centimeters (cc) or less in accordance with Article 3 of the Vehicle Management Act.

2 is a perspective view showing a frame assembly for the power transmission device 2 of the chainless bicycle 1. The power transmission device 2 according to an embodiment of the present invention is mounted on a frame assembly as shown in Fig. 2. An embodiment in accordance with the present invention includes first and second horizontal frames 32 and 34, and first and second inclined frames 40 and 50. A pair of horizontal frames 32 and 34 are arranged in a line and placed on the left and right sides of the chainless bicycle 1. A first housing 10 having a cylindrical shape is disposed between the first horizontal frame 32 and the first inclined frame 40, and a second housing 20 having a cylindrical shape is disposed at the first horizontal frame 32 and the second frame 50 connection between. The first housing 10 includes a pedal shaft 100, a first shifting unit 200, a first helical gear 300, and a second helical gear 420, and the second housing includes a third helical gear 440, a fourth helical gear 500, and a second shifting Unit 600. The first horizontal frame 32 is provided with a power transmission shaft 400 therein. The first and second housings 10 and 20 are fitted with first and second housing covers 12 and 810.

Figure 3 is a cross-sectional view showing the power transmission for the chainless bicycle 1 The member of one side of the pedal 102 of the transporting device 2, and Fig. 4 is an exploded perspective view showing the assembled state of Fig. 3. Fig. 5 is a cross-sectional view showing members on one side of the rear wheel 3 of the power transmission device 2 for the chainless bicycle 1, and Fig. 6 is an exploded perspective view showing the assembled state of Fig. 5.

As shown in FIGS. 3 and 6, the power transmission device 2 according to an embodiment of the present invention graphically includes a pedal shaft 100, a first shifting unit 200, a first helical gear 300, and a second and a second The power transmission shaft 400 of the slant gears 420 and 440, the fourth helical gear 500, the second shifting unit 600, and the rear axle 700.

The pedal shaft 100 is rotatably assembled into the first housing 10.

The first shifting unit 200 is mounted on the first housing 10 to output power by increasing the rotational speed of the pedal shaft 10 using a plurality of planetary gear units having a plurality of gear trains. As shown in FIG. 3, the first shifting unit 200 mainly includes a bracket 210, a planetary gear set 220, a ring gear set 230, a sun gear set 240, a power output shaft 250, and a first locking unit 270.

The bracket 210 includes a body 211 having a substantially disk shape. The bracket 210 is provided at its center with a pedal shaft connecting pipe 214 in which the pedal shaft 100 is assembled. Therefore, the bracket 210 rotates together with the pedal shaft 100. The support rod 212 protrudes from a virtual circumference around the pedal shaft connecting tube 214 formed on the surface of the bracket 210 such that the planetary gear set 220 is assembled around the support rod 212. In this case, at least three support rods 212 are spaced apart from one another by the same spacing. At the same time, a one-way clutch bearing (not shown) can be inserted between the pedal shaft connecting tube 214 and the pedal shaft 100. One-way clutch bearing (not shown) The carriage 210 is rotated only when the pedal shaft 100 is rotated forward. When the pedal shaft 100 is rotated backward, the carriage 210 is idling. Therefore, the power is transmitted to the rear wheel 3 only when the pedal shaft 100 is rotated forward.

The planetary gear set 220 is rotatably assembled around the support rod 212 of the bracket 210. Install at least three planetary gear sets that rotate independently of each other. The planet gears 220a, 220b, and 220c have different diameters. Therefore, when the planetary gears 220a, 220b, and 220c are assembled around the support rod 212, the planetary gears 220a, 220b, and 220c are sequentially arranged from the planetary gear 220a in accordance with the order of their diameters. Although the planetary gear set 220 according to the present embodiment includes three planetary gears 220a, 220b, and 220c, four or five planetary gears may be utilized such that the first shifting unit 200 may have four or five shift stages.

The ring gear set 230 includes three ring gears 230a, 230b, and 230c. In this case, the ring gears 230a, 230b, and 230c are internally engaged with the planetary gears 220a, 220b, and 220c of the planetary gear set 220, respectively, so that they can rotate independently of each other. In detail, the first ring gear 230a meshes with the first planetary gear 220a, the second ring gear 230b meshes with the second planetary gear 220b, and the third ring gear 230c meshes with the third planetary gear 220c. Further, locking projections 232a, 232b, and 232c are formed on the outer circumference of each of the ring gears 230a, 230b, and 230c at the same pitch. Specifically, the ring gears 230a, 230b, and 230c preferably have the same outer diameter such that the ring gears 230a, 230b, and 230c smoothly mesh with the tip end portion 273 of the brake 272 which will be described later.

The sun gear set 240 includes three sun gears 240a, 240b, and 240c The three sun gears 240a, 240b, and 240c are externally engageable with the three planetary gear sets 220. The sun gears 240a, 240b, and 240c have different diameters from each other. In this case, the sun gears 240a, 240b, and 240c may be integrated with each other.

Meanwhile, the gear ratio between the sun gears 240a, 240b, and 240c and the planetary gears 220a, 220b, and 220c is in the range of 1:0.2 to 3. The details thereof will be described later.

The power take-off shaft 250 has a tubular shape and is fixed to one side of the sun gear 240c of the sun gear set 240. In this case, the pedal shaft connecting tube 214 of the bracket 210 is assembled into the power output shaft 250 such that the pedal shaft connecting tube 214 is supported by the power output shaft 250. In addition, the power output shaft 250 does not contact the pedal shaft connecting pipe 214 by the bearing B.

Meanwhile, the power output shaft support plate 260 is a disk having a power output shaft insertion hole 262 at its center. The power take-off shaft support plate 260 is coupled to the support rod 212 of the bracket 210. In addition, the power take-off shaft support plate 260 is provided at one surface thereof with support protrusions 264 having an annular shape and corresponding gear sets 220, 230, and 240 so that the gear sets 220, 230, and 240 are firmly engaged with each other without being separated from them. And, supporting the power output shaft 250. The bearing B is inserted between the power output shaft 250 and the power output shaft jack 262.

Meanwhile, since the first locking unit 270 disposed at the first shifting unit 200 has the same structure and operation as the second locking unit 670 disposed in the second shifting unit 600, the description thereof will be made together with the second locking unit 670 Description.

The first helical gear 300 is fixed to one side of the power output shaft 250 to correspond to The speed of the power output from the first shifting unit 200 rotates.

At the same time, the first housing 10 is provided with the first housing cover 12 to prevent the first shifting unit 200 and the first helical gear 300 from being exposed to the outside.

The power transmission shaft 400 is provided at its both ends with second and third helical gears 420 and 440, and is mounted on the first horizontal frame 32 such that the second and third helical gears 420 and 440 are placed at the first and second, respectively. Housings 10 and 20. In this case, preferably, a bearing (not shown) is inserted between the power transmission shaft 400 and the first horizontal frame 32, thereby minimizing energy loss due to friction. The second helical gear 420 of the power transmission shaft 400 meshes with the first helical gear 300, thereby orthogonally converting the rotational force of the first helical gear 300.

The fourth helical gear 500 is a second bracket 610 that is critically coupled to the second shifting unit 600, and meshes with the third helical gear 440 of the power transmission shaft 400, thereby rotating the rotational force of the power transmission shaft 400 and the supply thereof. The converted rotational force is to the second shifting unit 600.

The second shifting unit 600 is mounted to the second housing 20. The second shifting unit 600 outputs power by increasing the rotational speed of the fourth helical gear 500 using a planetary gear unit having a plurality of gear trains. The bracket 610, the planetary gear set 620, the ring gear set 630, the sun gear set 640, the output shaft 650, and the second lock unit 670 of the second shifting unit 600 disposed therein are provided with those members of the first shifting unit 200 The same construction. Therefore, in the following, the components to be described will be emphasized in their characteristics.

The bracket 610 has a support rod 612 provided on one side thereof to support the planetary gear set 620 and is fixedly assembled to the fourth helical gear 500 on a pair of sides thereof The body 611 of the fourth helical gear fixing member 614. The power take-off shaft 650 is tubular and extends through the sun gear set 640 such that the power take-off shaft 650 is assembled into the fourth helical gear mount 614. The length of the power take-off shaft 650 extending from one side of the sun gear set 640 is longer than the length of the power take-off shaft 650 extending from the other side of the sun gear set 640. Further, the power output shaft support plate 600 is a disk plate having a power output shaft insertion hole 662 at its center and combined with a support rod 612 of the bracket 610. In addition, the power take-off shaft support plate 660 is provided on one surface thereof with a support protrusion 664 having an annular shape and corresponding gear sets 620, 630, and 640 such that the gear sets 620, 630, and 640 are not strongly engaged with each other out of position thereof. And supporting the opposite side of the power take-off shaft 250.

At the same time, the rear axle 700 is assembled into the hub axle (not shown) of the rear wheel 3 such that the rear axle 700 is integrated with the rear wheel 3.

Therefore, if the power output shaft 650 is critically coupled and rotated with the rear axle 700, the rear wheel 3 is driven at a speed corresponding to the power output from the second shifting unit 600. In this case, preferably, a one-way clutch bearing (not shown) is inserted between the rear axle 700 and the hub axle (not shown). When the rear wheel 3 is rotated forward at a speed faster than the speed of the power output shaft 650 of the second shifting unit 600, the second shifting unit 600 is prevented from being rotated by the rear wheel 3 by allowing the rear wheel 3 to idle. The impact is needed.

Meanwhile, as shown in FIG. 5, one end of the rear wheel axle 800 is integrated with the second casing cover 810 on the opposite side of the opening/closing second casing, and is assembled into the power output shaft 650. In this case, the rear wheel axle 800 supports the power output shaft 650, the rear axle 700, and the rear wheel 3, and a distal end of the rear wheel axle 800 is by using a screw and a connecting hole as shown in FIG. 60 connections to As for the rear wheel 3, it will not be separated from the frame assembly.

Therefore, in the second shifting unit 600, the components of the gear sets 620, 630, and 640 and the power output shaft 650 are integrated with each other by the power output support plate 660 and the support rod 612 of the bracket 610, so that The wheel 3, like the rear wheel axle 800, can be easily attached/detached from the frame assembly.

Figure 7 is an exploded perspective view showing the locking unit 270 in accordance with the present invention. The first and second locking units 200 and 600 are mounted to the first and second housings 10 and 20, respectively, to adjust the power output speeds of the first and second shifting units 200 and 600. The first locking unit 270 has the same structure and operation as those of the second locking unit 670. Therefore, hereinafter, the first locking unit 270 will be representatively described. As shown in FIG. 7, the first locking unit 270 mainly includes a brake 272, a body 274, and a wire 276.

The stopper 272 is provided at its lower end with a tip end portion 273 by which the tip end portion 273 moves along the guide groove 14 formed in the opposite direction of the first casing 10. The tip end portion 273 is substantially cylindrical and the lower end of the tip end portion 273 is conical. The tip end portion 273 is selectively locked by one of the locking projections 232a, 232b, and 232c of the ring gears 230a, 230b, and 230c to stop the unsynchronized ring gears 230a, 230b, and 230c.

The body 274 has a space portion to surround the core on which the brake 272 moves along the guide groove 14, and is formed on the outer surface of the first housing 10.

The body 274 is provided with an openable cover 275 on one side thereof. In particular, the shell The cover 275 is provided with at least one guide 275a such that the brake 272 is assembled around the guide 275a for longitudinal sliding. In this case, the spring 278 is assembled around the guide 275a to elastically support the brake 272. If the spring force of the spring 278 is released as shown in FIG. 4, the release of the spring 278 causes an idling state in which the brake 272 cannot mesh with any of the ring gears 230a, 230b, and 230c of the first shifting unit 200, so that A shifting unit 200 is idling. This feature is more advantageous for electric bicycles or motorized bicycles that are respectively connected to an electric motor or a main engine.

One end of the wire 276 is fixed to the stopper 272, and a pair of side ends of the wire 276 are connected to the moving rod (not shown) mounted on the handle of the chainless bicycle 1 through the case cover 275. When the travel bar (not shown) is in operation, the wire 276 allows the brake 272 to move along the guide slot 14 under the resilient support of the spring 278.

[Operation of power transmission device for chainless bicycle]

Hereinafter, the operation of the power transmission device 2 of the chainless bicycle 1 according to an embodiment of the present invention will be described with reference to the drawings.

According to an embodiment of the present invention, the first and second shifting units 200 and 600 perform shifting of the following chainless bicycle 1 by using a planetary gear unit having a plurality of gear trains.

The planetary gears 220a, 220b, and 220c, or 620a, 620b, and 620c are rotated by the bracket 210 or 610 at the rotational speed of the pedal shaft 100 or the fourth helical gear 500 to rotate against the pedal shaft 100 or the true axle center 800. . In addition, ring gears 230a, 230b that respectively mesh with the inside of the planetary gears 220a, 220b, 220c, 620a, 620b, and 620c, One of 230c, 630a, 630b, and 630c is fixed by brake 272 or 672, and the appropriate planet or sun gear is rotated. In this case, the remaining ring gear is idling. Thus, the power take-off shaft 250 or 650 that is securely assembled into the sun gear set 240 or 640 rotates such that shifting of the chainless bicycle 1 is performed.

Meanwhile, the first and second shifting units 200 and 600 are configured to increase the pedal ratio according to the gear ratio between each of the sun gears 240a, 240b, 240c, 640, 640b, and 640c and the planetary gears meshed with the sun gear. The rotational speed of the shaft 100 outputs power. For example, if the gear ratio between the sun gear 240a or 640a and the planetary gears 220a or 620 is 1:1.5, the power output shaft 250 rotates at four times the rotational speed of the pedal shaft 100. Further, if the gear ratio between the sun gear 240b or 640b and the planetary gears 220b or 620b is 1:1, the power output shaft 250 is rotated at three times the rotational speed of the pedal shaft 100. If the gear ratio between the sun gear 240c or 640c and the planetary gears 220c or 620c is 1:0.5, the power output shaft 250 rotates at twice the rotational speed of the pedal shaft 100. Therefore, the first and second shifting units 200 and 600 can perform a three-stage shift. In this case, since the first and second shifting units 200 and 600 are connected to each other through the power transmission shaft 400, the power transmission device 2 for the chainless bicycle 1 can perform a nine-stage shift in total. In addition, when the number of gears of the planetary gear set 220 or 620, the ring gear set 230 or 630, and the sun gear set 240 or 640 of the first and second shifting units 200 and 600 is increased, nine or more stages of shifting can be carried out.

As described above, the power transmission device 2 for the chainless bicycle 1 includes the first and second shifting units 220 and 600 using the planetary gears, so that the phases Different gear ratios like traditional chain bicycles can be implemented.

In addition, when the chainless bicycle 1 is in a stationary state by using the locking unit 270 or 670, the chainless bicycle 1 can perform shifting. In addition, since the chainless bicycle 1 has a more simplified structure, the chainless bicycle 1 can exhibit superior durability and long-lasting power transmission.

In the second shifting unit 600, the components of the gear sets 620, 630, and 640 and the power output shaft 650 are coupled to the support rods 612 of the bracket 610 through the power output support plate 660 so as to be integrated with each other, so that the rear wheels 3 can be Easily connect to/remove from the frame assembly.

The above is intended to be illustrative only and not limiting. Any equivalent modifications or alterations to the spirit and scope of the invention are intended to be included in the scope of the appended claims.

1‧‧‧Unchained bicycle

10‧‧‧First housing

12‧‧‧First cover

14, 24‧‧‧ guiding slot

100‧‧‧ pedal shaft

101‧‧‧cross bar

102‧‧‧ pedal

2‧‧‧Power transmission device

20‧‧‧ second housing

200‧‧‧First shifting unit

210‧‧‧ bracket

211, 274, 611‧‧‧ ontology

212, 612‧‧‧ support rod

214‧‧‧Pedal shaft connecting tube

220, 620‧‧‧ planetary gear sets

220a, 220b, 220c, 620a, 620b, 620c‧‧‧ planetary gears

230, 630‧‧ ‧ ring gear set

230a, 230b, 230c, 630a, 630b, 630c‧‧ ‧ ring gear

232a, 232b, 232c, 632a, 632b, 632c‧‧‧ locking projections

240, 640‧‧‧Sun Gear Set

240a, 240b, 240c, 640a, 640b, 640c‧‧‧ sun gear

250, 650‧‧‧ power output shaft

260, 660‧‧‧ power output shaft support plate

262, 662‧‧‧ power output shaft jack

264, 664‧‧‧ support protrusions

270‧‧‧First locking unit

272, 672‧‧‧ brakes

273, 673‧‧‧ tip part

275, 675‧‧‧ can open the cover

275a, 675a‧‧‧ introducer

276, 676‧‧‧ wires

278, 678‧ ‧ spring

3‧‧‧ Rear wheel

32‧‧‧First horizontal frame

34‧‧‧ second horizontal framework

300‧‧‧First helical gear

40‧‧‧First inclined frame

400‧‧‧Power transmission shaft

420‧‧‧second helical gear

440‧‧‧third helical gear

50‧‧‧Second inclined frame

500‧‧‧fourth helical gear

60‧‧‧connection hole

600‧‧‧Second gear unit

610‧‧‧second bracket

614‧‧‧4th helical gear fixing

670‧‧‧Second locking unit

700‧‧‧ Rear axle

800‧‧‧ Rear wheel axle

810‧‧‧Second cover

B‧‧‧ bearing

1 is a perspective view showing a chainless bicycle equipped with a power transmission device according to an embodiment of the present invention; and FIG. 2 is a perspective view showing a power transmission device for a chainless bicycle. Figure 3 is a cross-sectional view showing a pedal shaft for a power transmission device for a chainless bicycle; Fig. 4 is an exploded perspective view showing the assembled state of Fig. 3; and Fig. 5 is a sectional view showing a member shown on one side of the rear wheel of the power transmission device for the chainless bicycle; FIG. 6 is an exploded perspective view showing the assembled state of FIG. 5; and FIG. 7 is an exploded perspective view showing One of the locking units of the present invention.

1‧‧‧Unchained bicycle

100‧‧‧ pedal shaft

101‧‧‧cross bar

102‧‧‧ pedal

2‧‧‧Power transmission device

3‧‧‧ Rear wheel

Claims (9)

A power transmission device for a chainless bicycle, the power transmission device comprising: a first shifting unit mounted on a pedal shaft and outputting power by increasing a rotational speed of the pedal shaft; a first helical gear system mounting Rotating on the pedal shaft at a speed corresponding to the power of the first shifting unit; a power transmission shaft is disposed on one end of the second helical gear that meshes with the first helical gear; The quadrangular helical gear train meshes with a third helical gear disposed at a opposite end of the power transmission shaft; a second shifting unit outputs power by increasing a speed of the fourth helical gear; and a rear axle shaft corresponds to Rotating the speed of the power of the second shifting unit, wherein the first shifting unit comprises: a first bracket system firmly coupled with the pedal shaft; at least three first planetary gear sets are independently rotated and assembled Between at least three first support rods projecting from a virtual circumference on a surface of the first bracket, wherein each of the first planetary gear sets includes at least three having a diameter different from a first planetary gear set; a first ring gear set including first ring gears respectively meshing with the first planetary gears and rotating independently of each other; a first sun gear set including the first a planet gear externally meshed and having a diameter different from each other and a first sun tooth integrated with each other a first power output shaft is securely assembled into the first sun gear set; and a first locking unit selectively stops one of the first ring gears; and wherein the second shifting unit The method includes: a second bracket is firmly coupled to the fourth helical gear; at least three second planetary gear sets are independently rotated from each other and assembled on at least one of the surfaces of the second bracket a periphery of the second support rod protruding from the virtual circumference, wherein each of the second planetary gear sets includes at least three first planetary gears having diameters different from each other; a second ring gear set including the second and second a second ring gear that meshes internally and independently rotates from each other; a second sun gear set includes a second sun gear that respectively meshes with the second planet gears and has a diameter different from each other and is integrated with each other a second power output shaft is firmly assembled into the second sun gear set; and a second locking unit selectively stopping one of the second ring gears; wherein the first lock The unit includes: a first brake is moved along a first guiding groove formed in the first housing when elastically receiving the support, and is formed by each of the first ring gears The locking projection structure is selectively locked; a first system is formed on the first housing to enclose the movement track of the first brake and has a first openable cover; a first wire is used to adjust a position of the first brake; wherein the second locking unit comprises: a second brake is coupled to the second guide formed on the second casing when elastically receiving the support The slot moves and is selectively locked by a second locking projection formed on each of the second ring gears; a second system is formed in the second housing to enclose the movement of the second brake And having a second openable cover; and a second lead for adjusting a position of the second brake. The power transmission device of claim 1, wherein the first shifting unit and the first helical gear are mounted on a first housing supporting the pedal shaft; the fourth helical gear and the second shifting The unit is mounted on a second housing supporting a rear wheel axle, the power transmission shaft being mounted on a horizontal frame connecting the first housing and the second housing and having a tubular shape; and the first and the first The two housings have first and second housing covers. The power transmission device of claim 1, wherein in the first shifting unit, the first support rods supporting the planetary gear sets and a pedal shaft connecting tube are formed on the first bracket a surface of the pedal shaft that is securely inserted into the pedal shaft connecting tube, the first sun gear set being disposed on a side thereof having the power output shaft, wherein the pedal shaft connecting tube is assembled into the power output shaft and Supported by the power output shaft, a first power output shaft support plate is additionally provided, wherein the first power output shaft support plate is combined with the first support rod to prevent the first sun, The planet, and the ring gear set are disengaged from their position such that the first sun, planet, and ring gear sets are effectively intermeshing and supporting the power take-off shaft, and the first bevel gear is securely assembled on the power take-off shaft around. The power transmission device of claim 1, wherein in the second shifting unit, the second support rods supporting the second planetary gear sets are formed on a surface of the second bracket, a fourth helical gear fixing member is formed on a pair of sides of the second bracket, and a second power output shaft supporting plate is additionally provided, wherein the second power output shaft supporting plate is coupled with the second supporting rod to prevent the The second sun, planet, and ring gear sets are disengaged from their positions such that the second sun, planet, and ring gear sets are effectively intermeshing and support a pair of sides of the second output shaft, and have a tubular shape The second power output shaft extends from the sun gear set such that the second power output shaft is assembled into the fourth helical gear mount and supported by the fourth helical gear mount. The power transmission device of claim 3, wherein in the first shifting unit, the first planetary gears are sequentially arranged from the first bracket according to a diameter thereof, and wherein In the second shifting unit, the second planetary gears are sequentially arranged from the second bracket in accordance with the order of their diameters. The power transmission device of claim 1, wherein the first sun gear and the first planetary gears have a ratio of 1:0.2 to 3, and wherein the second sun gears and the second Planetary gears have a 1:0.2 to The ratio of 3. The power transmission device of claim 1, wherein in the first ring gear set, the first ring gears have the same outer diameter as each other, and the plurality of first locking protrusions are each An equally spaced surface of an outer circumferential surface of the first ring gear, and wherein, in the second ring gear set, the second ring gears have the same outer diameter as each other, and the plurality of second locking protrusions And equidistantly spaced on an outer circumferential surface of each of the second ring gears. The power transmission device of claim 1, wherein the first cover further comprises a first guide inserted into the first brake to guide the first brake such that the first brake slidably moves And wherein the second cover further includes a second guide inserted into the second brake to guide the second brake such that the second brake is slidably movable. The power transmission device of claim 1 or 4, wherein the pedal shaft is coupled to an electric motor or an engine.