JPH0653390U - Bicycle gearbox - Google Patents

Abstract

(57) [Abstract] [Purpose] Multi-stage sprocket with a large number of sprockets with different diameters for changing the rotation speed of the rear wheel of the bicycle and low speed and high speed gears are used on the rear side and front side of the bicycle. (EN) Provided is a bicycle transmission device capable of preventing the structure from becoming complicated and preventing an increase in production cost due to the production of a multi-stage sprocket. [Structure] A front transmission composed of a first planetary gear set having a first sprocket and a second sprocket, and a rear transmission composed of a second planetary gear set having a third sprocket and a fourth sprocket. Install the machine on one of the saddle tube ST and the rear wheel tip RT,
The front and rear derailleurs for connecting the chain C to each sprocket and connecting the chain C to the chain C are installed to simplify the structure, and the speed of the bicycle can be changed in four stages by mixing the four sprockets. it can.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a bicycle transmission. More specifically, a planetary gear set and a sprocket each having a sprocket formed on the outer circumference are installed on the front side and the rear side of the bicycle, respectively, and the speed is changed by mixing the planetary gear set and the sprocket. The present invention relates to a bicycle transmission that simplifies the vehicle and improves the speed ratio.

[0002]

[Prior art]

 In general, a bicycle has front wheels and rear wheels of a predetermined diameter rotatably mounted on a frame having a handle and a saddle, a drive sprocket is installed in the center of the frame, and only rear wheels can be driven forward. A freewheel is installed, and by connecting it with a chain, the rear wheel is rotated by the rotation of the drive sprocket and the bicycle is moved forward.

As shown in FIG. 6, a general structure of the bicycle is a saddle support SS and a saddle tube ST, a fork F and a lower tube DT, and a frame FR composed of a crossbar CB, a saddle S and a steering wheel. By connecting H, the front wheel T is installed on the terminal hawk chip FT of the hawk F, and the rear wheel T ′ is installed on the terminal rear wheel tip RT of the saddle support SS, and the saddle tube ST and the lower tube DT are connected. A drive sprocket 50, in which a pedal P is rotatably inserted, is installed in the coupling portion, and a free wheel 51 connected to this by a chain is installed in a rear wheel tip RT and the rear wheel is rotated according to the rotation of the pedal P. T'is designed to rotate.

Here, the free wheel 51 is usually formed with a single-step sprocket, and the driving force from the driving sprocket 50 is transmitted at a driving force of a predetermined rotation ratio and a rotation speed to rotate the rear wheel T ′. . Therefore, in order to increase or decrease the driving force and the rotation speed, the free wheel 51 is formed of a multi-stage sprocket 52 as shown in FIG. 7 so that the driving force and the rotation speed can be changed by the difference in the number of teeth of the sprocket. A rear derailleur 54 for moving the position of the chain C coupled thereto is installed.

When the rear derailleur 54 moves the chain C to one of the multi-stage sprockets 52, the driving force and the rotation speed change at a predetermined ratio. Driving Sprockets The operation of the rear derailleur 54 installed on the rotating rear wheel T ′ to which the driving force of the rocket 50 is transmitted will be described. The rear wheel T fixed rotatably between the rear wheel tip RT by the hub 55 and the fixed shaft 56. A multi-stage sprocket 52 is installed on the 'side, and a rear derailleur 54 is installed on one of the outer sides of the rear wheel tip RT. Further, the chain C is coupled to the guide gear 57 of the rear derailleur 54 and operated by a cable (not shown), and the rear derailleur 54 having the ring means 58 is coupled to the guide gear 57 by rotating around the hinge 59. The chain C is moved to one sprocket in the multi-stage sprocket 52 to change the speed ratio.

At this time, in order to further improve the speed ratio of the multi-stage sprocket 52, the drive sprocket 50 is switched to the high-speed sprocket 60, 61 as shown in FIG. Therefore, in order to connect the chain C to the two sprockets 60 and 61, the fastening band 62 is connected to the saddle tube ST and the front derailleur 53 is moved by the linking means 63 at high speed and low speed gears. The chain C is supported by the chain guide 65. Then, the chain C is moved to one of the high speed and low speed sprockets 60 and 61 by the rotational movement of the chain guide 65. In FIG. 8, the state where the chain C is connected to the low speed sprocket 61 is shown by a dotted line.

Here, as described above, if the speed of the bicycle is changed according to the gear ratio of each gear of the multi-stage sprocket 52, a speed ratio of about 1.3 to 3.7 can usually be obtained.

[0008]

[Problems to be solved by the device]

 However, as described above, by selectively connecting the front side high-speed and low-speed sprockets 60, 61 and the rear multi-stage sprocket 52 with the chain C, the speed of the bicycle can be changed depending on the difference in the number of teeth of the sprockets. Requires a sprocket suitable for each speed ratio, and a large number of sprockets with different diameters must be installed, which complicates the configuration and increases the production cost.

The present invention has been made in view of the above problems, and in order to change the rotation speed of the rear wheel of a bicycle, a multi-stage sprocket having a large number of sprockets with different diameters is provided on the rear side and the front side of the vehicle. An object of the present invention is to provide a bicycle transmission that prevents the complication of the configuration caused by the use of the sprocket and improves the limitation of the speed ratio due to the use of the multi-stage sprockets.

[0010]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention provides a first planetary gear set having a crank shaft inserted in a saddle tube so as to rotate in one direction, and a second sprocket formed on an outer periphery thereof, and the first planetary gear set. A first sprocket provided on the planetary gear set side so as to rotate in one direction at the same speed as the rotation of the crankshaft; and a front transmission having a front derailleur fixed to the saddle tube and moving the chain to each sprocket, A second planetary gear set attached to the hub between the rear wheel tips and having a fourth sprocket installed on the outer periphery, a third sprocket arranged on the side of the second planetary gear set and rotating in one direction, and one of the It has a rear derailleur that is fixedly installed on the rear wheel tip and that moves the chain with the third sprockets and the second planetary gear set. It is configured to have a rear transmission. Further, preferably, the first planetary gear set has a flange formed on one of the saddle tubes, a first line gear is fixed to the flange, and a plurality of first planetary pinions are provided on an outer periphery of the first line gear. The first planetary pinion and the first line gear are arranged inside the first ring gear having the second sprocket formed on the outer peripheral surface thereof, and the front is provided by ratchet means between the first planetary pinion and the first line gear. The second planetary gear set is connected to a hub by a second planetary gear set via a ratchet means, and a plurality of second planetary pinions are arranged on the outer periphery of the second line gear to form an outer periphery. The second planetary pinion is arranged on a rear carrier having a fourth sprocket formed therein, and the second planetary pinion and the second line gear are arranged inside a second ring gear fixed to one rear wheel tip. Constitution Are you.

Here, the planetary gear set is usually composed of a linear gear centered on a circle, a plurality of planet pinions that rotate around the linear gear, and a ring gear that surrounds the planet pinion. One can be fixed and the other two can be used as input and output to accelerate and decelerate. Therefore, the front transmission forms a sprocket on the outside of the ring gear, and the line gear is fixed to increase the rotation ratio by the revolution and rotation of the planet pinion that rotates by the crankshaft.The rear transmission fixes the ring gear. Then, a sprocket is formed on the carrier to increase the rotation ratio by rotation and revolution of the linear gear and planet pinion that rotate together with the hub. Since the rotation ratio (speed ratio) is determined by the gear ratio of the linear gear, the planet pinion and the ring gear, it is possible to determine an appropriate speed ratio.

[0012]

【Example】

 Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. FIG. 1 is a schematic view showing a bicycle transmission according to the present embodiment, which includes a front transmission 4, a rear transmission 6, and a chain connecting the two transmissions, and the chain is the transmission. Is wrapped around the sprocket.

The front transmission 4 is rotatably connected to a saddle tube ST, and a crank shaft CS and a pedal P are attached to the side surfaces thereof. Similarly to this, the rear transmission 6 is rotatably connected to the fixed shaft 56 of the hub 5. The planetary gear sets 2 and 9 act on the front and rear parts of the transmission, respectively. Each planetary gear set is provided as a means for changing the rotational speed or rotational force of this transmission. Therefore, it is possible to rotate the sprockets of this planetary gear set faster or slower than the speed of their central hub.

FIG. 2 is a partially enlarged view showing the front transmission 4 of the transmission according to the present embodiment. The first sprocket 1 is provided at one end of the saddle tube ST into which the crankshaft CS of the pedal P is inserted. Is mounted, and the first planetary gear set 2 is mounted inside thereof. A second sprocket 3 which is the same as the first sprocket 1 is formed on the outer periphery of the first planetary gear set 2. The front carrier 14 will be described later.

A front derailleur 53 connected to a fastening band 62 fixed to a saddle tube ST and a link means 63 is arranged above the front transmission 4, and a chain guide 65 of the front derailleur 53 is attached to the front derailleur 53. Has chain C in it.

When the driver rotates the pedal P while the chain C is connected to the first sprocket 1, the chain C is not connected due to the rotation of the first sprocket 1 which rotates only in one direction. The second sprocket 3 idles, and as shown in FIG. 3, the hub 5 provided between the fixed shafts 56 connecting the two rear wheel tips RT and the rear transmission 6 arranged on the hub 5 side. Is rotated by the chain C.

At this time, if the chain C connected to the rear transmission 6 is connected to the third sprocket 7 by the guide gear 57 of the rear derailleur 54 fixed to the rear wheel tip RT side, the rear wheel T ′ (FIG. 8). Can be rotated 1: 1 without changing the speed. That is, in the rear transmission 6, a third sprocket 7 that rotates in the same manner as the hub 5 is provided on the hub 5, and a fourth sprocket 8 is formed on the outer periphery of the third sprocket 7. Since the second planetary gear set 9 is provided, the chain C can be connected to the third sprocket 7 to rotate the rear wheel T ′ without changing the speed.

The second planetary gear set 9 having the third sprocket 7 and the fourth sprocket 8 is inserted into the rear wheel tip RT while being rotatably inserted only in one direction via ratchet means. It is fixed on one side. Here, when a gear shift lever (not shown) is operated to operate the front derailleur 53, the chain guide 65 moves, the chain C is connected to the second sprocket 3, and the first planetary gear set 2 operates.

Here, the structure and function of the first planetary gear set 2 shown in FIG. 4 will be described. A flange 10 is formed on the side of the saddle tube ST, a first line gear 11 is fixed thereto, and a large number of first planetary pinions 12 that revolve and rotate according to the first line gear 11 are formed on the first line. It is arranged on the outer periphery of the gear 11. Then, the first linear gear 11 and the first planetary pinion 12 are arranged so that the first planetary pinion 12 meshes with the first ring gear 13 and the front carrier capable of transmitting power by the crankshaft CS. A first planetary pinion 12 is attached to 14. As a result, the driving force of the pedal P is transmitted to the front carrier 14, and the first ring gear 13 having the second sprocket 3 formed by the rotation and revolution of the first planetary pinion 12 rotates faster than the rotation of the pedal P. I am able to do it.

At this time, since the rotational forces of the first sprocket 1 and the second sprocket 3 are different, when the chain C moves from the first sprocket 1 to the second sprocket 3, the chain C moves to the first and second sprockets. During 1 and 3, it may be caught or unable to change gears and may be stopped or separated. Therefore, in order to prevent this, the front carrier 14 and the first sprocket 1 are formed with projections 15 and 16 capable of transmitting the rotational force of the pedal P and rotating in one direction. The projections 15 and 16 form ratchet means in pairs with the projections 15 'and 16' formed on the crankshaft CS so as to be coupled to the crankshaft CS, so that the forward drive force can be slipped when the chain C moves. Prevents the chain C from leaving.

Here, since the first, second, third and fourth sprockets (1, 3, 7, 8) have the same diameter, the increase in the rotation speed of the first planetary gear set 2 is caused by the first line gear. 11 is fixed, and the first planetary pinion 12 rotates and revolves along the outer periphery of the first line gear 11 by driving the front carrier 14, thereby changing the rotation speed of the first ring gear 13 that is the second sprocket 3. The number of rotations of the third sprocket 7 can be increased at the same time as the speed ratio of about 3.09.

In order to further increase the speed of the bicycle, the rear derailleur 54 is operated to move the chain C to the fourth sprocket 8 of the rear transmission 6. Here, the configuration of the rear transmission 6 arranged on the hub 5 side into which the fixed shaft 56 is inserted will be described with reference to FIG. As shown in FIG. 5, a third sprocket 7 and a rear carrier 18 are attached to a sprocket insertion portion 17 extending from the hub 5, and the rear carrier 18 is provided with a large number of second planet pinions 19. There is. A second linear gear 20 is arranged between these second planet pinions 19. Further, the second planetary pinion 19 is configured to rotate and revolve on its inner peripheral surface and to have a second planetary gear set 9 including a second ring gear 21 fixed to the rear wheel tip RT. A normal freewheel 51 is formed on the hub 5.

When the fourth sprocket 8 to which the chain C is connected by the rear derailleur 54, that is, the rear carrier 18, rotates, the plurality of second planet pinions 19 rotate and revolve on the inner peripheral surface of the second ring gear 21. Thus, the second line gear 20 can be rotated faster than the rotation speed of the rear carrier 18. Therefore, the hub 5 connected to the second line gear 20 and the rear wheel T ′ connected to the hub 5 by spokes (not shown) move the second planetary gear sets 2 and 9 by the rotation of the second sprocket 3. It is possible to obtain a speed ratio of about 4.36. If the first sprocket 1 and the fourth sprocket 8 are connected by the chain C, a speed ratio of about 1.41 smaller than the above speed ratio can be obtained.

Here, the speed ratio obtained by mixing the sprockets (1, 3, 7, 9) can be obtained by the following equations (1) and (2).

R1 (Ψ + Φ) = R2 (θ−Ψ) (1) R3 (θ−Ψ) = R2 (θ−Ψ) (2) α: Ring gear rotation angle R1: Line gear inner diameter Ψ: Planetary pinion Center movement angle R2: Planet pinion inner diameter θ: Planet pinion rotation angle R3: Ring gear inner diameter Φ: Line gear rotation angle

Here, if the sprockets (1, 3, 7, 8) in the formulas (1) and (2) have the same straight diameter and the same number of teeth, the second sprocket 3 has the first linear gear 11 Since it is fixed, Φ = 0, and because the second line gear 21 is fixed, α = 0. As shown in FIG. 5, the speed ratio due to the mixing of each sprocket is the case of the first sprocket 1 and the third sprocket 7. 1: 1, 1: 3.09 for the first sprocket 1 and the fourth sprocket 8, and 1: 1.41 for the second sprocket 3 and the second sprocket 7, and the second sprocket 3 and the fourth sprocket. In case of 8, it becomes 1: 4.36.

If the second line gear 20 and the third sprocket 7 are rotatable on the inner peripheral surfaces of the second line gear 20 and the third sprocket 7 only in a fixed direction when contacting with the hub 5. Together, the protrusions 22 and 22 'that can rotate in one direction are formed so that the rotational speeds of the third and fourth sprockets 7 and 8 are synchronized when the chain C is moved, and the hub 5 that contacts the protrusions 22 and 22' is formed. Two sets of protrusions 23 and 23 'which are paired with the protrusions 22 and 22' are formed at the positions. These projections 22, 22 'and 23, 23' form ratchet means.

[0028]

[Effect of device]

 As described above, the present invention provides a front transmission including the second sprocket and the first sprocket, which is the first planetary gear set, and a rear transmission including the fourth sprocket and the third sprocket, which is the second planetary gear set. Also, by arranging a front derailleur that can move the chain and a rear derailleur, it is possible to perform a predetermined gear shift by mixing the first and second planetary gear sets and the second and third sprockets. In addition, the production cost can be reduced because it is not necessary to use a multi-stage sprocket having a complicated structure.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a connection relationship between a front transmission and a rear transmission.

FIG. 2 is a partially enlarged view showing a state in which the front transmission of the present invention is mounted on a hanger log of a saddle tube.

FIG. 3 is a partially enlarged view showing a state in which the rear transmission of the present invention is mounted on a rear wheel tip.

FIG. 4 is a partial perspective view showing the front transmission of FIG. 1 in a disassembled state.

5 is an exploded perspective view showing the rear transmission of FIG. 2 in an exploded manner.

FIG. 6 is a front view showing a bicycle equipped with a general multi-stage transmission.

FIG. 7 is a partially enlarged view showing a state in which a conventional rear transmission is mounted on a rear wheel tip.

FIG. 8 is a partially enlarged view showing a state in which a conventional front transmission is mounted on a saddle tube.

[Explanation of symbols]

 1 1st sprocket 2 1st planetary gear set 3 2nd sprocket 4 front transmission 6 rear transmission 7 3rd sprocket 8 4th sprocket 9 2nd planetary gearset 10 flange 11 1st line gear 12 1st planetary pinion 13 3rd 1 ring gear 14 front carrier 15,15 ', 16,16' ratchet means 22,22 ', 23,23' ratchet means 50 drive sprocket 51 freewheel 53 front derailleur 54 rear derailleur 55 hub C chain CS crankshaft RT rear wheel Tip ST Saddle tube T'Rear wheel

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Lee Seong-Ai 103-220 Seosan-dong, Mapo-gu, Seoul, Republic of Korea 103-220 (72) Inventor Lee Fool-day, 14 rooms, Aomuro, Aom-dong, Gangnam-gu, Seoul, Republic of Korea No. 1008 (72) Inventor Kim ▲ Bin ▼ 91, No. 1, Shinsang-dong, Jung-gu, Incheon, South Korea

Claims (5)

[Scope of utility model registration request] 1. A first planetary gear set having a second sprocket formed on an outer periphery thereof, the first planetary gear set being coupled to a crank shaft inserted in a saddle tube so as to rotate in one direction, and the crank shaft on the first planetary gear set side. A first sprocket provided to rotate in one direction at the same speed as the rotation, and a front transmission fixed to a saddle tube and having a front derailleur for moving the chain to each sprocket, attached to a hub between the rear wheel tips A second planetary gear set having a fourth sprocket on its outer circumference, and a third planetary gear set disposed on the side of the second planetary gear set and rotating in one direction.
A bicycle transmission comprising a sprocket and a rear transmission fixedly installed on one rear wheel tip and having a rear derailleur for moving a chain by the third sprocket and a second planetary gear set. 2. The first planetary gear set has a flange formed on one side of a saddle tube, a first line gear is fixed to the flange, and a plurality of first planetary pinions are arranged on an outer periphery of the first line gear. Then, the first planetary pinion and the first linear gear are arranged inside the first ring gear having the second sprocket formed on the outer peripheral surface, and the front carrier is formed by ratchet means between the crankshaft and the crankshaft. Claim 1
The bicycle transmission described. 3. A second planetary gear set is coupled to a hub with a second line gear via ratchet means, and a plurality of second planet pinions are arranged on the outer periphery of the second line gear, and the second planetary gear set is arranged on the outer periphery. The second carrier is attached to the rear carrier on which the fourth sprocket is formed.
The bicycle transmission according to claim 1 or 2, wherein the planetary pinions are arranged, and the second planetary pinion and the second linear gear are arranged inside a second ring gear fixed to one rear wheel tip. 4. The bicycle transmission according to claim 2, wherein the first sprocket and the front carrier are attached to the crankshaft via ratchet means for providing only forward drive force. 5. The bicycle transmission according to claim 3, wherein the third sprocket and the second line gear of the second planetary gear set are attached to the extension hub via ratchet means for providing only forward drive force.