TW201515926A - Assembled crank for ratio enhancing of rotation speed - Google Patents

Abstract

The present invention relates to a crank assembly increasing rotation ratio which more increases the number of rotations of a rear wheel with respect to one rotation of a crank arm when a diameter of a sprocket installed in a crank shaft is regarded to be regular. The crank assembly increasing the rotation number, having the crank shaft supported at a shell arranged in a frame structure to be rotatable; and crank arms having one ends fixated on both ends of the crank shaft respectively to have their phases opposite to each other, is configured to comprise a planet gear carrier formed on one end of one side crank arm and having a planet gear concentrically arranged around the crank shaft; a sun gear having a tube shape where one side is fixated on one side of the shell and the other side wraps one side of the crank shaft at an interval, and having the outer circumferential surface engaged with the planet gear; and a ring gear rotationally supported on the outer circumferential surface of the sun gear, having the inner circumferential surface engaged with the planet gear, and including one or more sprockets on the outer circumferential surface, wherein the diameter of the sun gear is greater than that of the planet gear.

Description

Increase the rotation ratio of the crank assembly

The invention relates to a crank assembly for increasing a rotation ratio. Specifically, the diameter of the sprocket provided on the crankshaft of the bicycle is constant, and the rotation ratio of the rear wheel rotation of the bicycle is increased relative to the rotation of the crank arm. Crank assembly.

Generally, a bicycle is a moving tool that converts a rider's pedal rolling motion into a pushing force and can move a farther distance than the pedal rolling motion.

Here, the power transmission device that converts the rider's pedal rolling motion into a driving force includes: a crank assembly, and the outer casing provided on the frame structure is a support substrate, and is performed by a rider's pedal rolling motion. Rotating; a chain connecting the large sprocket of the crank assembly and the small sprocket disposed on the rear wheel.

The crank assembly includes a drive shaft rotatably disposed in the outer casing, and one end of the crank arm fixed to the two ends of the drive shaft so that the phases of the crank arms are opposite to each other; the large sprocket is disposed on one side of the drive shaft.

Here, the size ratio of the large sprocket to the small sprocket is set to rotate the rear wheel more by the rider's pedal rolling action.

In order for the rider to move the long distance with a small force, it is necessary to form the large sprocket to be larger than the small sprocket, or to arrange and connect a plurality of gears or sprockets in the section from the outer casing to the rear wheel side.

However, when the large sprocket is formed to be larger than the small sprocket, it is difficult to enlarge the diameter of the large sprocket, in particular, a bicycle that can ride on a road such as MTB, and the large sprocket collides or breaks due to a protruding portion on the road. Therefore, it is required to reduce the size of the large sprocket.

In the case of arranging and connecting a plurality of gears or sprockets from the outer casing to the rear wheel side, as disclosed in the Korean Patent No. 10-1195127, it is difficult to secure a space because a plurality of constituent elements are provided. Excessively, except when damage or breakage occurs locally in these components, maintenance and replacement are difficult.

Conventional technical literature

Patent literature

Republic of Korea Patent No. 10-1195127

The present invention has been made to solve the problems of the prior art, and an object thereof is to provide a rear wheel that can rotate more with respect to a rider's pedal rolling motion even if the diameter of the large sprocket is reduced, and The components are gathered together to easily ensure the installation space, and at the same time, the bicycle is lightweight, and by simplifying the assembly, it is easy to repair and replace the crank assembly that constitutes the increased rotation ratio of the components.

According to the present invention, the planetary gear guided by the planetary gear carrier rotates and revolves along the circumference of the sun gear. At this time, the diameter of the planetary gear is smaller than the diameter of the sun gear, and thus, the rotation speed increases as compared with the revolution angle. And rotating the ring gear in a ratio corresponding to the linear velocity, thereby reducing the diameter of the large sprocket while rotating the rear wheel more than the rider's pedal rolling action, since the constituent elements are concentrated together It is easy to install in a conventional installation space, and realizes bicycle weight reduction, and it is easy to repair and replace constituent elements by simplifying assembly.

10‧‧‧ shaft shell

12‧‧‧ crankshaft

14‧‧‧ crank arm

16‧‧‧ planetary gear shaft

18‧‧‧ planetary gear carrier

22‧‧‧First bearing

26‧‧‧ planetary gear

28‧‧‧ bearing parts

30‧‧‧Sun Gear

32‧‧‧Sun Gear Body

34‧‧‧Sun Gear Bracket

36‧‧‧Second bearing

38‧‧‧ring gear

42‧‧‧ bracket

14'‧‧‧ crank arm

14‧‧‧ crank arm

16'‧‧‧ planetary gear shaft

18‧‧‧ planetary gear carrier

18'‧‧‧ planetary gear carrier

20‧‧‧Installation slot

20'‧‧‧Installation slot

22'‧‧‧First bearing

22A‧‧‧Outside

22B‧‧‧Inner wheel

26/P‧‧‧

30'‧‧‧Sun Gear

30/P‧‧‧

32'‧‧‧Sun Gear Body

32A‧‧‧First Insertion Department

32B‧‧‧Second Insertion

32C‧‧‧Sawtooth

34A‧‧‧Protruding

34b‧‧‧Flange

36A‧‧‧Outside

36B‧‧‧Second Insertion

38/P‧‧‧

38a‧‧‧ring gear base plate

38b‧‧‧Support parts

40a, 40b‧‧‧Sprocket

B‧‧‧Coupling bolt

F‧‧‧ frame structure

G‧‧‧ gear

M1, M2‧‧‧ peripheral interval

O‧‧‧ track

P‧‧‧ pedal

P/S‧‧‧ pedal shaft

P1‧‧‧Contact

S‧‧‧ Shell

SP‧‧‧ Spline

SP/H‧‧‧ splined slot

1 is a perspective view showing a configuration of a crank assembly for increasing a rotation ratio according to an embodiment of the present invention, and a disassembled perspective view for describing an assembly relationship of the respective structures; FIGS. 2a to 2d are for describing the first diagram. A cross-sectional view of each structural assembly process; FIG. 3 is a diagram for describing the arrangement relationship between the sun gear of the assembled state of the second drawing and the planetary gear including the planetary gear carrier and the ring gear, and the gears of the gears The configuration diagram of the relationship between the two; the fourth diagram is based on the truncation of the sun gear and the planetary gear and the ring gear according to Fig. 3, and the system diagram showing the action relationship by the outer curve formed by the revolution and the rotation of the planetary gear And Fig. 5 is a cross-sectional view showing the construction of a crank assembly for increasing the rotation ratio according to a modified embodiment of the present invention and for describing the respective assembly relationship.

The terms used in this specification and the scope of the patent application are not to be construed as a general or dictionary meaning. The principle that the concept of the term can be appropriately defined by the inventor in order to best explain his invention should be interpreted as a technique consistent with the present invention. The meaning and concept of thought.

The embodiments and the configurations shown in the present specification are merely preferred embodiments of the present invention, and do not all represent the technical idea of the present invention. Therefore, it should be understood that at the time of the application of the present invention, there are other alternatives to the present invention. Equals and variants.

In the present specification, the one side and the other side of the direction are defined as one side or one side of each of the components and components located in the direction in which the sprocket is provided, centering on the outer casing provided in the frame structure. The opposite side is designated as the other side or the other side, and the one end portion and the other end portion are end portions selected from any one of the other constituent relationships in the longitudinal direction.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Referring to FIGS. 1 to 2d, a crank assembly for increasing the rotation ratio according to an embodiment of the present invention is provided with a crank shaft rotatably supported by the shaft housing 10 in a casing S disposed in the frame structure F. 12. The ends of the crankshaft 12 are fixed at their respective ends in the longitudinal direction of the crank arms 14, 14' so that the phases are opposite to each other.

As in the conventional bicycle structure, the pedal P is rotatably provided around the pedal shaft P/s at the other end of each of the crank arms 14, 14'.

Referring to FIGS. 1 to 2d and FIG. 5, a spline sp and a spline groove sp/h are formed at both end portions of the crankshaft 12, and the crank arms 14 and 14' corresponding thereto are formed. The spline sp and the spline groove sp/h for inserting the end portion of the crank shaft 12 have grooves or holes of the spline groove sp/h and the sp sp, and a rotation preventing portion such as a convex shape, thereby preventing by the combination Rotate each other.

Further, the assembled state of the crankshaft 12 and the crank arms 14, 14' is coupled to the crankshaft 12 through the coupling bolts B through the crank arms 14, 14', so that the coupled state can be stably maintained.

A planetary gear carrier 18 is formed at one end portion of the crank arm 14 and 14' in the longitudinal direction of the crank arm 14 on the side of the casing S, and the planetary gear carrier is provided with one or more planetary gear shafts arranged concentrically around the crankshaft 12. 16.

Referring to FIGS. 2a to 2b, the planetary gear carrier 18 is separately configured as a side crank arm 14, but is not limited thereto, and may be formed by a casting process or a molding process during the process of manufacturing the crank arm 14. After the above process is forged or even post-cut, the planetary gear carrier 18 and the one side crank arm 14 are integrally formed.

That is, the planetary gear shaft 16 can be arranged concentrically around the crank shaft 12 on the other side of the one side crank arm 14.

The number of the planetary gear shafts 16 provided in the planetary gear carrier 18 may be two or more. In this case, it is preferable to arrange them at equal intervals around concentric circles.

When the other side of the planetary gear carrier 18 or the planetary gear carrier 18 is integrally formed with the one side crank arm 14, a shallow mounting groove 20 is formed on the other side of one end of one of the crank arms 14 in one side, and the mounting groove is formed. In the inner region of the concentric circle formed by the planetary gear 16, a first bearing 22 for supporting one end of the sun gear 30, 30' is provided on the inner wall of the mounting groove 20 and the other side in the deep direction.

When the first bearing 22 is formed of a radial bearing, please refer to the enlarged portion of the arrow "II a" of Fig. 2a, the bearing outer wheel 22a is embedded in the inner wall of the mounting groove 20, and the other side in the depth direction is preferably further formed. The step portion 24 of one side of the outer wheel 22a of the first bearing 22 is selectively contacted, thereby being spaced apart from the inner wheel 22b of the first bearing 22.

This has a complementary relationship that supports the arrangement of the sun gears 30, 30' to the crankshaft 12, while at the same time rotatably supporting the one side crank arms 14 to the sun gears 30, 30'.

The mounting groove 20' shown in the enlarged portion of the arrow "IIb" in Fig. 2a is a modification of the above-described planetary gear carrier 18. When the planetary gear carrier 18' is assembled to the one side crank arm 14, it can be formed as a planetary gear. A through hole having a step portion d from one side direction of the carrier 18' to the inner side of the other side direction.

The through hole is inserted into the first bearing 22 from one side of the planetary gear carrier 18', and the other side edge portion of the first bearing outer wheel 22a is locked at the step portion d, and then, on the crank shaft 14 and the planet The gear carrier 18' is pressed and fixed during the combination.

The first bearing 22' shown in the enlarged portion of the arrow "IIc" in Fig. 2a is a modification of the first bearing 22 described above, indicating that a thrust bearing can be applied. At this time, the first bearing 22' determines that the one side crank arm 14 is assembled at one end of the sun gear 30'.

In the above configuration, the planetary gear 26 is rotatably supported by the planetary gear shaft 16.

It is preferable to further include a bearing member 28 such as a bushing or a bearing between the planetary gear shaft 16 and the planetary gear 26 so that the planetary gear 26 can freely rotate with respect to the planetary gear shaft 16.

Referring to FIGS. 1 to 2d and FIG. 5, the sun gears 30, 30' are cranks that are fixed to the side of the casing S on the other side, and are extended from the casing S toward the one side. The tubular shape of the shaft 12 engages the planet gears 26 along its circumference on the outer wall.

For the sun gears 30, 30', the sun gear 30 shown in the embodiment of Figs. 1 to 2d will be described in further detail.

The sun gear 30 includes a short tube type sun gear main body 32 provided between one side portion of the outer casing S and the other side of one end portion of the side crank arm 14 corresponding to one side of the outer casing, and one end portion of the sun gear main system The first insertion portion 32a corresponding to the inner wheel a of the first bearing 22 is formed, and the other end portion is formed with a second insertion portion 32b corresponding to the inner wheel 36b of the second bearing 36, and is formed at the first insertion portion 32a. The outer peripheral surface between the second insertion portions 32b includes a gear g' that meshes with the gear g' formed in the planetary gears 26, and the gear g' protrudes beyond the outer peripheral surfaces of the first insertion portion 32a and the second insertion portion 32b.

In the sun gear main body 32, a plurality of serrations 32c projecting in the other side direction around the other end portion are formed in the second insertion portion 32b.

The sun gear 30 is provided with a sun gear holder 34 to fix the sun gear main body 32 while fixing the other side of the sun gear main body 32 to one side of the outer casing S.

Referring to FIG. 1 or FIG. 2c, the sun gear carrier 34 is in the shape of a sleeve in which one side is inserted into the inner side of the second bearing 36, and includes a protruding portion 34a formed with an outer peripheral surface interposed between the serrations 32c of the sun gear main body 32. a spline sp and a spline groove sp/h for inserting the serration 32c and supporting the inner surface of the serration 32c; the flange portion 34b is formed to extend outward from the other side of the projection 34a, approaching the facing ring The other side of the gear 38 supports its aligned state, and the other end is fixed to one end of the outer casing S.

That is, the sun gear carrier 34 is fixed to one end of the outer casing S by the flange portion 34b, and the protruding portion 34a which is extended from the flange portion 34b is spline sp and the spline groove sp/h is interposed between the second bearing 36 and the second bearing 36. The inner side of the inner wheel 36b of 36 is engaged with the serration 32c of the opposite sun gear main body 32.

The sun gear main body 32 and the sun gear bracket 34 are coupled to the crank arm 14 by the coupling bolt B in the process of coupling to the crankshaft 12, and the components between the sun gear main body and the sun gear bracket are mutually pressed to stably maintain each other. The state of combination.

At this time, the flange portion 34b of the sun gear 34 approaches the other side of the ring gear 38, and restricts the sliding movement of the ring gear 38 with the sun gear 30 as a supporting substrate.

An oil groove or gasket 44 is formed on at least one side of the flange portion 34b of the facing sun gear bracket 34 and the other side surface of the ring gear 38. The oil groove attracts a lubricant such as butter to reduce the ring gear. 38 rotates to create friction with each other, the gasket being slidably contacted relative to the opposite side to prevent lubricant flow or to prevent external foreign matter or other oil from flowing in.

The other side of the planetary gear carrier 18 and at least one of the sides of the ring gear 38 with respect to the planetary gear carrier are further provided with the oil groove or gasket 44`.

Referring to Fig. 1, Fig. 2c and Fig. 2d, a bracket 42 is provided for fixing the sun gear bracket 34 to the outer casing S, and the bracket has a sleeve type portion that is inserted into one end portion of the outer casing S, and has a slave portion. One end of the sleeve-shaped portion is extended toward the outside to form a disc-shaped flange-shaped portion.

First, the bracket 42 is fixedly coupled to the housing S by a fixing screw N through a sleeve type portion.

Then, the fixing of the sun gear bracket 34 is provided with the flange portion 34b of the sun gear bracket 34 corresponding to the flange portion of the fixed bracket 42, and the flange portion of the fixing screw N through the bracket 42 is coupled to the sun gear bracket 34. The flange portion 34b.

The bracket 42 is shown in the above description and shown as a separate structure coupled to the sun gear carrier 3, but by providing the bracket 42 so as to correspond to the size of the outer casing S, when the size of the outer casing S is fixed, In the process of manufacturing the sun gear carrier 34, the components corresponding to the bracket 42 can be integrally formed.

The gear g formed on the outer circumferential surface of the sun gear 32 is supported on the other side and one side of the inner bearings 22b and 36b of the first bearing 22 and the second bearing 36 corresponding to both sides of the gear serration.

Preferably, the portion from the supported portion to the front end of the gear g is formed into a taper whose diameter gradually expands toward the outer side in the center direction between the first insertion portion 32a and the second insertion portion 32b to be protected from the first bearing 22 The outer wheel 22a and the second bearing 36 interfere with the outer wheel 36a.

The gear g of the sun gear main body 32 is formed to protrude beyond the outer peripheral surfaces of the first insertion portion 32a and the second insertion portion 32b because the first bearing 22 and the second bearing 36 are spaced apart from each other and include the first bearing and the second The planet gears 26 of the bearings are isolated and designed from the set size.

The diameter of the sun gears 30, 30' will be further described in detail when describing the relationship of the sun gears, but the diameter of the sun gears 30, 30' is preferably larger than the diameter of the planet gears 26.

The first insertion portion 32a and the second insertion portion 32b of the sun gear 30 may be embedded in the inner wheel 22b of the corresponding first bearing 22 and the inner wheel 36b of the second bearing 36, respectively, but for easy assembly, preferably configured to be slidable Inserted structure.

The sun gear 30' of Fig. 5 is the same as the sun gear 30 of Figs. 1 to 2d, and is fixed to the casing S, and preferably has a bracket 42' having a corresponding shape.

The bracket 42' has the same shape as the bracket 42 described above, and can be integrally formed with the sun gear bracket 34'.

The sun gear 30' is provided with a sun gear bracket 34' coupled to a fixing screw penetrating the bracket 42'.

The sun gear 34' is coupled to the bracket 42' and is fixed by being pressed against the inner wheel 36b' of the second bearing 36' of the ring gear 38'.

Referring to FIG. 5, as an additional technical configuration, a support protrusion 42a' which protrudes from the other side surface of the inner wheel 36b of the second bearing 36' is formed on one side of the bracket 42', and is squeezed on the opposite side. The pressing portion 34a' is such that the other side of the sun gear carrier 34' corresponds to one side of the inner wheel 36b' of the second bearing 36'.

A sun gear main body 32' having a gear g formed on one side of the sun gear bracket 34' is formed, and the main system of the sun gear is extended along a circumference of the sun gear bracket toward the one side, and the gear g is along the sun gear bracket. The circumferential direction of the outer peripheral surface meshes with the planetary gears 26.

Referring to FIG. 5, the sun gear 30' is formed integrally with the sun gear main body 32', and one side of the sun gear bracket 34' is expandable to a planetary gear that blocks the planetary gear 26 from the relative position. The range in which the shaft 16 is disengaged.

The inner circumferential surface of the ring gear 38' may be formed to have a diameter larger than the inner circumferential surface of the ring gear 38.

In the sun gear 30 or the sun gear 30' of the above two embodiments, the sun gear 30 is assembled to the ring gear in one direction by coupling one side crank arm 14 to the crank shaft 12 or detaching the crank arm 14 from the crank shaft 12. 38 and the planetary gear 26 are detached from the ring gear and the planetary gear, and the sun gear 30' is for assembling or disassembling the ring gear 38'. The process of disassembling or assembling the sun gear 30' to the outer casing S.

In the sun gear 30 or the sun gear 30' of the above two embodiments, the sun gear 30 has an effect of further improving the efficiency of disassembling or assembling the respective constituent elements.

Referring to FIGS. 1 , 2 c , 2 d , and 5 , the ring gears 38 , 38 ′ are rotatably supported by the outer circumferences of the sun gears 30 , 30 ′ by the second bearings 36 , 36 ′. The inner peripheral surface is formed with a gear g'' that meshes with the gear g' of the planetary gear 26, and one or more sprockets 40a, 40b, ... are provided on the outer peripheral surface in the longitudinal direction of the crankshaft 12.

The structure of the ring gears 38, 38' will be further specifically described with reference to FIG. 1, FIG. 2c, and FIG. 2d. The ring gears 38, 38' include: the ring gear base plate 38a is guided by the planetary gear carrier 18 to surround the planetary gears. A short tube shape on the periphery of the orbit of 26, a gear g'' engaged with a gear g' formed on the outer peripheral surface of the planetary gear 26 is formed on the inner peripheral surface; and a support member 38b is formed on the ring gear substrate 38a. The one side is annular, and the inner circumference is formed close to the outer circumference of the corresponding sun gear 30.

In the above-described technical configuration, the ring gear base plate 38a and the support member 38b of Figs. 1 to 2d together with the planetary gear carrier 18 at the opposite positions restrict the isolation of the planetary gears 26 and divide the operation region.

In each of the above-described configurations, when the sun gears 30 and 30', the planetary gears 26, and the ring gears 38 and 38' are assembled, the connection driving relationship is stably maintained, and the crankshaft 12 is arranged in the vertical direction as a center. The concentric arrangement in which the crankshaft 12 is extended toward the outside is disposed, and the connection relationship between the outer casing S, the crankshaft 12, and the crank arm 14 can save the installation area.

Hereinafter, the assembly relationship of the above configuration will be described with reference to FIGS. 3 and 4.

First, the sun gears 30, 30' are fixed to the side of the casing S, and the planetary gears 26 rotate together with the crank arms 14, 14' to which the planetary gear carrier 18 is fixed at one end of the crankshaft 12, whereby the sun gear 30, The 30' meshing is rotated and moved along the orbital track C around it while rotating the ring gears 38, 38'.

At this time, the sun gears 30, 30' mesh with the planetary gears 26 and the ring gears 38, 38' to prevent adjacent gears from sliding with each other, and the gears are rounded around each other. 30/p, 26/p, 38/p rotate.

Here, referring to Fig. 5, when the rounding diameter r of the sun gears 30, 30' is formed to be three times the circular diameter r' of the planetary gears 26, it is rotated with respect to one of the crank arms 14, 14', and is located on the planet. One point P on the gear circle 26/p is rotated three times from one contact P1 of the sun gear 30/p contact, and then contacted with the sun gear 30/p to form an epicycloid track. O.

Each point P on the trajectory O is expressed by a section angle (θ) in which the angle formed by the revolution track C of the planetary gear 26 is subdivided until the planetary gear 26 rotates once.

Thereby, the interval between the points P from the contact point P1 is gradually enlarged, and the maximum interval (at the outermost periphery) is formed from the center of the sun gear 30, 30' through the outermost peripheral sections M1 to M2 of the section angle (θ). The linear velocity: l), then, the interval between the points P is gradually reduced until reaching the contact point Ph that is in contact with the sun gears 30, 30'.

Since the portion of the planetary gear 26 that transmits power to the ring gears 38, 38' is always from the center of the sun gear 30, 30' to the outermost portion, the moving distance N41 to the planetary gear 26 of the segment angle θ is M2, the line speed l at the outermost point is larger.

In other words, the planetary gears 26 are rotated by the revolving position as the support substrate when the sun gears 30 and 30' revolve. Therefore, the ring gears 38, 38' are rotated at a higher ratio with respect to one of the planetary gears 26.

By exemplifying the rotation ratio, when the diameter of the sun gears 30, 30' is twice (2:1) of the planetary gears 26, the rotation ratio of the ring gears 38, 38' is increased by about 1.3 times with respect to one revolution of the planetary gears 26. When the diameter of the sun gears 30, 30' is three times (3:1) of the planetary gears 26, the rotation ratio of the ring gears 38, 38' is increased by about 1.6 times with respect to one of the planetary gears 26, and the sun gears 30, 30 When the diameter of the planetary gear 26 is 4 times (4:1), the rotation ratio of the ring gears 38, 38' is increased by about 1.77 times with respect to one of the planetary gears 26, and the diameter of the sun gears 30, 30' is a planet. When the gear 26 is 5 times (5:1), it revolves with respect to one of the planetary gears 26, and the ring gears 38, 38' When the turning ratio is increased by about 1.9 times and the rounding diameter r of the sun gear 30, 30' is smaller than the rounding diameter r' of the planetary gear 26, the planetary gear is rounded 26/p only when the crank arms 14 and 14' are rotated more than once. The upper point can be restored to the origin, and therefore, the rotation ratio of the ring gears 38, 38' is reduced with respect to one revolution of the planetary gears 26.

When the circular diameter r of the sun gears 30, 30' is the same as the circular diameter r' of the planetary gears 26, when the crank arms 14, 14' rotate once, a point on the planetary gears 26/p is restored to the origin. Therefore, the rotation ratio of the ring gears 38, 38' is at the same level with respect to one revolution of the planetary gears 26.

When the rounding diameter r of the sun gears 30, 30' is larger than the rounding diameter r' of the planetary gears 26, it is a matter of course that the rotation ratio of the ring gears 38, 38' is increased with respect to one revolution of the planetary gears 26.

At the same time, considering the driving relationship between the crankshaft 12 and the outer casing S and the crank arms 14, 14' and the ratio of the sprocket 40a, 40b... and the gears g, g`, g``, the sun gear 30, 30' The ratio of the circular diameter r to the circular diameter r' of the planetary gear 26 is preferably in the range of 1.5 to 5:1.

Therefore, with the present invention, as the crank arms 14, 14' rotate, the rotational speed ratio of the ring gears 38, 38' increases, whereby the sprocket can be significantly reduced relative to the rotation of the crank arms as compared with the prior art. Diameter R.

10‧‧‧ shaft shell

12‧‧‧ crankshaft

14‧‧‧ crank arm

16‧‧‧ planetary gear shaft

18‧‧‧ planetary gear carrier

22‧‧‧First bearing

26‧‧‧ planetary gear

28‧‧‧ bearing parts

32‧‧‧Sun Gear Body

34‧‧‧Sun Gear Bracket

36‧‧‧Second bearing

38‧‧‧ring gear

42‧‧‧ bracket

14'‧‧‧ crank arm

34b‧‧‧Flange

34A‧‧‧Protruding

38a‧‧‧ring gear base plate

38b‧‧‧Support parts

40a‧‧‧Sprocket

40b‧‧‧Sprocket

B‧‧‧Coupling bolt

F‧‧‧ frame structure

P‧‧‧ pedal

P/S‧‧‧ pedal shaft

S‧‧‧ Shell

SP‧‧‧ Spline

SP/H‧‧‧ splined slot

Claims (9)

A crank assembly for increasing a rotation ratio, comprising: a crank shaft rotatably supported on a casing disposed on a frame structure; and a crank arm, each end portion being oppositely fixed to both ends of the crank shaft, wherein: a planetary gear carrier formed at one end of the one side crank arm, wherein the planetary gear is disposed concentrically around the crank shaft; the sun gear is fixed on one side of the outer casing, and the one side compartment surrounds the a tubular type on one side of the crankshaft, the outer peripheral surface of which engages with the planetary gear; the ring gear rotates with the outer peripheral surface of the sun gear as a supporting substrate, the inner peripheral surface meshes with the planetary gear, and the outer peripheral surface has one or more sprockets The diameter of the sun gear is greater than the diameter of the planet gear. A crank assembly for increasing a rotation ratio as claimed in claim 1, wherein one end of the sun gear is corresponding to one end of the one end portion of the crank arm corresponding to one end portion of the sun gear or one end of the sun gear A first bearing rotatably supported between the other side of the planetary gear carrier at one end of the sun gear is further provided. The crank assembly according to claim 1, wherein the ring gear comprises: a ring gear substrate, a short tubular shape surrounding a periphery of the orbit of the planetary gear, the inner peripheral surface meshing with the planetary gear; and the support member A plate type extending from the other side of the ring gear substrate toward the inner side, and the inner periphery is adjacent to the outer peripheral surface of the sun gear to support rotation. A crank assembly for increasing a rotation ratio according to claim 3, wherein a second bearing is further provided between an inner periphery of the support member and an outer peripheral surface of the sun gear corresponding to an inner periphery of the support member. A crank assembly for increasing a rotation ratio as claimed in claim 1, wherein a bearing member including a bushing or a bearing is further provided between the planetary gear shaft and the planetary gear. A crank assembly for increasing a rotation ratio as claimed in claim 2 or 4, wherein said The sun gear comprises: a sun gear main body, wherein the inner wheel corresponding to the first bearing and the second bearing respectively has a short tube shape inserted into one end portion and the other end portion, and an intermediate portion of the outer peripheral surface is formed to be engaged along the outer circumference thereof. The gear of the planetary gear is further formed with a plurality of serrations extending in the other end portion along the periphery of the end portion toward the other side; the sun gear bracket is formed at one end portion corresponding to the other end of the sun gear main body. The serration is inserted into the spline groove, and the other side portion is fixed to one end of the outer casing. The crank assembly according to claim 6, wherein the outer casing further comprises a sleeve-shaped portion inserted into one end of the outer casing and a disc-shaped flange portion extending outwardly from the sleeve-shaped portion. a bracket that is fixed by coupling a fixed screw to the sleeve-type portion and coupled to a corresponding one end of the outer casing, the sun gear carrier being fixed by being coupled to a flange-shaped portion penetrating the bracket The screws are fixed. The crank assembly according to claim 1, wherein the outer casing further comprises a sleeve-shaped portion inserted into one end portion of the outer casing and a disc-shaped convex portion formed to extend outward from an end portion of the sleeve-shaped portion. a sun gear, the sun gear includes: a sun gear bracket fixed to one side of a flange type portion of the bracket by a fixing screw; the sun gear main body is disposed along an inner circumference of one side of the sun gear bracket The tubular shape is extended in the lateral direction, and the outer peripheral surface is meshed with the planetary gear, and the sun gear bracket is integrally formed with the sun gear main body. The crank assembly according to claim 4 or 8, wherein the bracket further forms a supporting protrusion on a side of the flange-shaped portion opposite to the other side of the second bearing inner wheel, the sun gear bracket is One of the other sides is provided with a pressing portion corresponding to one side of the inner wheel of the second bearing, In the process of fixing the sun gear to the bracket, the inner wheel of the second bearing disposed between the support protrusion and the pressing portion is pressed and fixed.