JPH04176788A - Transmission device for bicycle - Google Patents

Abstract

PURPOSE:To enhance the rigidity of a driven rotating body itself, and its support rigidity and support precision by fixing a crank shaft into a fixed boss part formed in a cylindrical form extending in the crank shaft direction, and forming the driven rotating body from a nearly cup-shaped body part and a cylindrical boss part situated on its shaft center. CONSTITUTION:A driven rotating body 59 is formed of a nearly cup-shaped body part 59d enclosing the body part 54d of a carrier 54 and a cylindrical support boss part 59e inserted and fixed to its shaft center part, and the support boss part 59e is supported by the fixed boss part 54a of the carrier 54 through a bearing 57. An internal gear 59a is integrally formed on the inner circumferential surface top end part of the body part 59d of the driven rotating body 59, and geared with the third gear 53c of an epicyclic gear line 53. A front driving side bevel gear 59b is integrally formed on the outside surface of the body part 59d of the driven rotating body 59, and geared with a front driven side bevel gear 60 fixed to the front end of a drive shaft 13. As the body part of the driven rotating body is formed nearly into a cup shape, the rigidity of the driven rotating body itself can be improved, and the forming works of the inner gear and the driving bevel gear are facilitated.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is a bicycle transmission bag in which a planetary gear mechanism is arranged around the crankshaft! In particular, the present invention relates to improvements in the shape, support method, etc. of the driven rotating body on which the internal gear forming the planetary gear mechanism is formed.

[Conventional technology]

Conventionally, as a bicycle transmission device, for example, Japanese Patent Application Laid-Open No. 63-7
As described in Japanese Patent No. 4790, there is a planetary gear type transmission in which a planetary gear mechanism is arranged around a crankshaft driven by a crank pedal.

This fixes a carrier to the crank arm, arranges a driven rotating body within the carrier, rotatably supports the driven rotating body with a roller attached to the carrier, and supports a planetary gear train with the carrier. In addition, a sun gear is disposed around the crankshaft, an internal gear is formed on the inner circumferential surface of the driven rotating body to mesh with the gear of the planetary gear train, and a rear wheel drive sprocket is formed on the outer circumferential surface. It has a structure.

The output rotation from this transmission is transmitted from a sprocket formed on the outer periphery of the driven rotating body to the rear wheels via a chain.

[Problem to be solved by the invention]

By the way, the planetary gear type transmission described in the above-mentioned publication is for a bicycle in which the rear wheel is driven by a bicycle. Therefore, if the transmission described in the above-mentioned publication is applied as is to a shaft drive type bicycle, various problems will occur.

For example, in the case of a chain drive bicycle, the load that acts on the driven rotating body is mainly the load that acts in the rotational direction via the sprocket, so this driven rotating body is not required to have such high rigidity and strength. However, in the case of a shaft-driven bicycle, the driven rotating body is subjected to loads not only in the rotational direction but also in the bending direction, so it is necessary to increase the rigidity of the driven rotating body. In addition, since such a load is applied, it is necessary to increase the support rigidity of the driven rotating body, and since the output rotation is extracted by the bevel gear, in order to ensure meshing between the bevel gears, the driven rotating body It is also necessary to improve the support accuracy.

The present invention has been made in view of the above circumstances, and it is possible to improve the rigidity of the driven rotating body itself, its support rigidity, and support accuracy, and also to improve the formation of the drive side bevel gear and internal gear for taking out the output rotation. The purpose is to provide a transmission device that is easy to use and suitable for shaft drive bicycles.

[Means to solve the problem]

The present invention includes a crankshaft rotatably driven by crank arms on both sides, a carrier fixed to the crankshaft, and a driven rotating body rotatably disposed around the crankshaft.
a planetary gear train having a plurality of gears with different diameters supported by the carrier; a plurality of sun gears meshing with each gear of the planetary gear train and rotatably arranged around the crankshaft; An internal gear formed on a rotating body and meshing with one of the gears of the planetary gear train, a transmission mechanism that selectively fixes one of the sun gears, and only the rotational force from the carrier to the driven rotating body. and a one-way clutch mechanism for transmitting the input rotation of the crankshaft at a predetermined gear ratio, and extracts the input rotation of the crankshaft as the output rotation of the driven rotary body, and drives the drive shaft for driving the rear wheels with the driven rotary body. In the bicycle transmission device, the carrier has a fixed boss portion formed in a cylindrical shape extending in the direction of the crankshaft, the crankshaft is inserted and fixed into the fixed boss portion, and the driven rotating body is attached to a substantially bowl-shaped main body. and a cylindrical support boss located at the axis of the support boss, the support boss is rotatably supported by the fixed boss of the carrier, and the inner circumferential surface of the main body of the driven rotor is The invention is characterized in that the internal gear is formed on the outer surface of the main body, and a driving bevel gear that meshes with the driven bevel gear of the drive shaft is integrally formed on the outer surface of the main body.

[For production]

According to the bicycle transmission according to the present invention, since the main body of the driven rotating body is formed into a substantially bowl shape, the rigidity of the driven rotating body itself can be improved without making the driven rotating body thick.

Furthermore, an internal gear is formed on the inner circumferential surface of the approximately bowl-shaped main body, and a drive side bevel gear is formed on the outer surface.

And it is easy to form bevel gears.

In addition, the fixed boss part of the carrier supports the support boss part of the driven rotor, and the above-mentioned drive side bevel gear is formed on the outer surface of the main body part, so that the bevel gear and the drive shaft are connected to each other. The meshing position with the bevel gear and the support position of the driven rotating body substantially coincide, so that the bending moment acting on this support portion can be small.

Furthermore, since the cylindrical support boss portion of the driven rotor is supported by the cylindrical boss portion of the carrier extending in the crankshaft direction, the support rigidity and support precision of the driven rotor can be improved.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

1 to 8 are diagrams for explaining a bicycle transmission according to an embodiment of the present invention, in which FIG. 1 is a cross-sectional plan view of the front transmission, and FIGS. Figure 1 is a cross-sectional view taken along lines ■-■ and mm-m in Figure 1; Figure 4 is a partially sectional plan view of the rear transmission and sub-transmission; Figure 5 is a front view of the axle support pipe;
6 is a sectional view taken along the line Vl--Vl in FIG. 5, FIG. 7 is a sectional view taken along the line ■--■ in FIG. 4, and FIG. 8 is a right side view of the bicycle according to the embodiment.

In the figure, 1 is a bicycle equipped with the transmission device of this embodiment, and the bicycle 1 has a hend pipe 2a of a body frame 2.
A front fork 4, which pivotally supports the front wheel 3 at its lower end, is pivotally supported so as to be steerable left and right, and a steering handle 8 is attached to the upper end of the front fork 4.
The seat 7 is attached to the upper end of the seat pipe 2C that is placed upright at the rear end position of the main pipe 2b, and the front end of the rear wheel drive device 9 is connected and fixed to the lower ends of the seat pipe 2C and the main vibe 2b. However, the rear wheel 5 is attached to the rear end of the rear wheel drive device 9. Note that 2d is a reinforcing pipe that connects the head pipe 2a and the 7-vib 2c, and 2e is a support pipe that connects the sorting pipe 2C and the rear part of the rear wheel drive device 9.

The rear wheel drive device 9 includes a front transmission 32 , a rear transmission 65 , a power transmission mechanism 68 that transmits the output rotation of the front transmission 32 to the rear transmission 65 , and a power transmission mechanism 68 that transmits the output rotation of the front transmission 32 to the rear transmission 65 .
8, and a drive frame 62 that supports them.

The drive frame 62 has a structure in which the front gear case 36 and the rear gear case 26 are connected by a right rear pipe lla, and the front end of the left rear pipe 1lbO is fixed to the front gear case 36 with a bolt 38. The front gear case 36 is a left and right split type in which left and right cases 36a and 36b are fastened with bolts 37, and a bracket 62a fixed to the front end of the right rear pipe lla is attached to the rear surface of the right case 36b. Fixed with bolts. Further, the rear gear case 26 is formed by fastening a case cover 26b to a case body 26a with bolts 29, and the rear end portion of the right rear pipe lla is fixed to the case cover 26b.

Further, the axle 10 is fixed in a frame between the axle support pipe 30 inserted and fixed into the case body 26a and the rear end of the left rear pipe 1lbO. The axle 10 is equipped with the planetary gear type rear transmission 165 (three-speed transmission), and the hub 5a of the rear wheel 5 is fixed to the casing of the device 65. Note that 31 is a cover that closes the insertion hole of the axle support pipe 3o.

The power transmission mechanism 68 has a main drive shaft 3 inserted into the right rear pipe 11a, a sub drive shaft 22 inserted into the rear case 26 so as to form the same straight line, and a front end connected to the front end of the main drive shaft 13. The driven side bevel gear 60 is fixed by spline fitting, and the rear drive side bevel gear 23 is fixed to the rear end of the auxiliary drive shaft 22 by spline fitting. The front driven bevel gear 60 is supported via a bearing 61 at the rear of the right case 36b, and the rear drive bevel gear 23 is supported via a bearing 24 at the case body 26a of the rear gear case 26. It is pivoted.

The bevel gear 23 meshes with a rear driven bevel gear 25 fixed to the right end of the rear transmission 65. In addition,
A cover 28 is fixed to the rear end of the case body 26a with bolts 29, and serves as a holding member for the bearing 24.

The auxiliary transmission device 12 is housed within the case cover 26b and has the following configuration. A carrier 1 having an internal gear 17a at the rear end of the main drive shaft 13
A sun gear 14 is attached to the front side of the sun gear 7 so as to be slidable in the axial direction, and a planetary gear 18 meshing with the sun gear 14 is supported by the carrier 17. Further, a driven rotating body 20 is fixed to the front end of the auxiliary drive shaft 22, and the planetary gear 18 is attached to the inner peripheral surface of the rotating body 20.
An internal gear is formed that meshes with the Note that this driven rotating body 20 has a bearing 2 near the front end of the case body 26a.
1.

Further, the sun gear 14 is urged backward by a spring 15,
It is designed to mesh with the internal gear 17a of the carrier 17, and can be separated from the internal gear 17a by moving it forward with the switching lever 16.

Moreover, when it moves forward, it engages with play) 14a. A switching shaft 63 to which this switching lever 16 is fixed
protrudes outward from the case cover 26b, and a switching cable (not shown) is connected to a drive lever 64 fixed to the protrusion, and the cable is connected to the steering handle 8.
It extends to the auxiliary gear shift lever located nearby.

The front transmission 32 is housed in the front gear case 36, and includes a carrier 54 fixed to the crankshaft 34, a driven rotating body 59 rotatably disposed around the crankshaft 34, and a driven rotating body 59 rotatably arranged around the crankshaft 34. 3 & u pivoted on carrier 54
the planetary gear train 53, the first to third sun gears 50 to 52 disposed around the crankshaft 34, a transmission mechanism 67 for selectively fixing any of the sun gears, and the carrier 5.
4 to the driven rotating body 59.

The crankshaft 34 is inserted into the front case 36, and its left and right ends are pivotally supported by the left and right cases 36a and 36b via bearings 41 and 39, and the left and right end portions are supported by the left and right protrusions. The right crank arms 33a and 33b are fixed. In addition, the crankshaft 34 and the crank arm 33a
, 33b may be fixed using nuts or bolts. 40 is a bearing holder, 42 and 43 are oil seals, and 44 is a lock nut.

The carrier 54 is formed by integrally forming a cylindrical fixed boss part 54a on the axis of a disc-shaped main body part 54d, and the crankshaft 34 is inserted into the fixed boss part 4a and is spline-fitted. There is.

The three sets of planetary gear trains 53 are arranged on the same circumference around the crankshaft 34 at intervals of 120 degrees,
There are first to third gears 53a to 53c each having a different diameter, and the right end of the central axis thereof is connected to the main body part 54 of the carrier 54.
d, and the left end is supported pivotally by a bracket 55. Further, this bracket 55 is fixed with a bolt 56 to a support portion 54e integrally formed with the main body portion 54d.

The first to third sun gears 50 to 52 are connected to the crankshaft 34
The first to third sun gears 5
The first to third gears 53a to 53c of each planetary gear train 53 mesh with gears 0 to 52, respectively.

The transmission mechanism 67 includes a pawl barrel 45 that is prevented from rotating by the left case 36a and is mounted on the crankshaft 34, and a pawl barrel 45 that is fixed to the left case 36a and mounted on the crankshaft 34
5, and the first to third locking pawls 4 disposed between the speed change cylinder 47 and the pawl barrel 45.
5b to 45d. The claw body 45 is
A plate 45a is cylindrical and fixed to one end.
is fixed to the left case 36a with bolts 46. The first to third locking pawls 45b to 45d are provided in pairs, respectively, and can be locked to ratchets 50a to 52a formed on the inner peripheral surfaces of the first to third sun gears 50 to 52. It is arranged to be able to rise and fall freely, and is urged into an upright state by a biasing spring 47f.

The speed change cylinder 47 has the first to third locking claws 45b to 4.
1st to 3rd claw holes 47c to 47 through which 5d can protrude outward
e, and is biased by a biasing spring 48 to a position where all of the above-mentioned locking pawls are retracted into the inside of the speed change cylinder. Further, an inner cable 4 of a speed change cable 49 is connected to one end 47b of a speed change arm 47a fixed to one end of the speed change cylinder 47.
9a is connected. This speed change cable 49 is connected to a speed change handle (not shown) disposed near the steering handle 8.

The driven rotating body 59 is connected to the main body portion 54 of the carrier 54.
It consists of a substantially bowl-shaped main body part 59d that surrounds d, and a cylindrical support boss part 59e that is inserted and fixed to the axis of the main body part 59d,
This support boss portion 59e is pivotally supported by the fixed boss portion 54a of the carrier 54 via bearings 57, 57. Note that the main body portion 59d and the support boss portion 59e may be formed integrally.

Further, an internal gear 59a is integrally formed at the tip of the inner peripheral surface of the main body 59d of the driven rotary body 59, and this is meshed with the third gear 53C of the planetary gear train 53.

On the outer peripheral surface of the main body 54d of the carrier 54, a pair of locking claws 54C are movable and a biasing spring 5
4b.

This locking claw 54c is connected to the main body portion 59 of the driven rotary body 59.
The one-way clutch mechanism 66 is configured such that it can be engaged with a ratchet 59c formed axially inwardly from the internal gear 59a of d, thereby transmitting only the rotational force from the carrier 54 to the driven rotating body 59. has been done.

Further, a front drive side bevel gear 59b is integrally formed on the outer surface of the main body portion 59d of the driven rotary body 59, and this is connected to a front driven side bevel gear 60 fixed to the front end of the main drive shaft 13. They mesh together. The meshing point between these umbrella gears is
It is located radially outward of the shaft supported by the fixed boss portion 54a of the carrier 54.

Next, the effects of this embodiment will be explained.

In the device of this embodiment, the rotation of the crankshaft 34 is transmitted to the driven rotating body 59 directly or via the planetary gear train 53,
The rotation of the driven rotary body 59 is transmitted to the rear wheel 5 via a transmission mechanism 68.
transmitted to.

When traveling in the first speed, the shift lever is rotated to the first speed position. Then, the speed change cylinder 47 rotates to a position where the first to third locking pawls 45b to 45d are recessed into the speed change cylinder 47, so that all the sun gears 50 to 52 become rotatable. As a result, the rotation of the crankshaft 34 is controlled by the locking pawl 54 disposed on the outer periphery of the carrier 54.
It is directly transmitted to the driven rotary body 59 via the driven rotary body 59, and is transmitted from the driven rotary body 59 to the main drive shaft 13.

When traveling in the second speed, the shift lever is rotated to the second speed position. Then, the speed change cylinder 47 rotates to a position where its third pawl hole 47g matches the third locking pawl 45d, and
As a result, the third locking pawl 45d projects outward from the third pawl hole 47e and locks onto the ratchet 52a of the third sun gear 52, thereby fixing the third sun gear 52. As a result, the planetary gear train 53 disposed on the carrier 54 is in the third position.
The gear 53c rolls on the third sun gear 52 while being meshed with the third sun gear 52. Therefore, the rotation of the crankshaft 34 is transmitted from the carrier 54 to the planetary gear train 53.
is transmitted to the driven rotary body 59 via the driven rotary body 59, thereby causing the driven rotary body 59 to rotate faster than in the case of the first speed. At this time, since the rotational speed of the driven rotary body 59 is faster than the rotational speed of the carrier 54, the locking pawl 54C attached to the carrier 54 does not engage with the ratchet 59c of the driven rotary body 59.

When traveling in the third speed, the shift lever is rotated to the third speed position. Then, the speed change cylinder 47 rotates to a position where its second pawl hole 47d matches the second locking pawl 45c,
As a result, the second locking pawl 45C projects outward from the second pawl hole 47d and locks onto the ratchet 51a of the second sun gear 51, thereby fixing the second sun gear 51. As a result, in the planetary gear train 53, the second gear 53b is connected to the second sun gear 51.
The second sun gear 51 rolls on the second sun gear 51 in a meshed state, and rotates at a higher speed than in the case of the second speed.

In this case as well, the rotation of the crankshaft 34 is transmitted from the carrier 54 to the driven rotating body 59 via the planetary gear train 53, but the rotational speed of this planetary gear train 53 is faster than in the second speed. Therefore, the driven rotating body 59 rotates faster than in the second speed. Note that in this third speed state, the third locking pawl 45d remains protruding from the third pawl hole 47e, but may be recessed into the speed change cylinder 47.

Note that when traveling in the fourth speed, the first locking pawl 45b is in the first position.
Since the sun gear 50 is fixed, the planetary gear train 53 rotates at a higher speed, resulting in faster rotation of the driven rotating body 59.

Next, the operation of the auxiliary transmission 12 will be explained with reference to FIG.

When the auxiliary gear shift lever is rotated to the direct connection position, sun gear 1
4 meshes with the internal gear 17a of the carrier 17, so that the rotation of the main drive shaft 13 is caused by the rotation of the main drive shaft and the planetary gears 18.
The rotation of the driven rotary body 20 in an integrated state transmits the power to the sub-drive shaft 22 .

When the auxiliary gear shift lever is rotated to the speed increasing position, the sun gear 1
4 moves forward, the meshing is released, and the plate 14a
Since the planetary gear 18 is meshed with and fixed to the sun gear 14 and does not rotate, the planetary gear 18 rolls on the sun gear 14 while rotating on its own axis, and thereby the rotation of the main drive shaft 13 is accelerated and the rotation of the auxiliary drive shaft 2 is increased.
2.

According to this embodiment, which operates as described above, a 4-speed front transmission 32, a 3-speed rear transmission 65, and a 2-speed auxiliary transmission 12 are provided, resulting in a total of 24 speeds. This multi-stage structure can be easily realized.

Further, according to the front transmission 32 of the present embodiment, the main body portion 59d of the driven rotary body 59 has a substantially bowl shape, so that the rigidity of the driven rotary body 59 itself can be improved without making it thick.

Further, an internal gear 59 is provided on the inner circumferential surface of the substantially bowl-shaped main body 59d.
Since the drive side bevel gear 59b is formed on the outer surface of the drive side bevel gear 59.a, this internal gear 59a and the drive side bevel gear 59.
b is easy to form.

Further, the fixed boss portion 54a of the carrier 54 is connected to the driven rotating body 5.
Since the drive side bevel gear 59b is formed on the outer surface of the main body part 59d following the support boss part 59e, the meshing position of the bevel gears 60, 59b with each other and the support position can be changed. are almost the same. Therefore, the bending moment acting on the support portion is small, and no unreasonable stress is generated in the support portion.

Furthermore, since the cylindrical fixed boss portion 54a of the carrier 54 extending in the crankshaft direction supports the similarly cylindrical support boss portion 59e of the driven rotor 59, the support rigidity and support of the driven rotor 59 are improved. Accuracy can be improved.

〔Effect of the invention〕

As described above, according to the bicycle transmission device according to the present invention,
Since the main body of the driven rotating body is approximately bowl-shaped, the rigidity of the driven rotating body itself can be improved, and the formation of internal gears and drive bevel gears is facilitated. Since the driven rotating body is supported on the outer periphery of the driven rotating body, the meshing position of the driving bevel gear can be brought close to the supporting position to suppress the generation of unreasonable stress, and the support rigidity and support accuracy of the driven rotating body can be improved. effective.

[Brief explanation of drawings]

1 to 8 are diagrams for explaining a bicycle transmission according to an embodiment of the present invention, in which FIG. 1 is a cross-sectional plan view of the front transmission, and FIGS. Figure 1 is a cross-sectional view taken along line 9-9 in Figure 1, Figure 4 is a partially sectional plan view of the rear transmission and auxiliary transmission, Figure 5 is a front view of the axle support pipe, and Figure 6 is the Figure 7 is a sectional view taken along the vt-vt line.
8 is a right side view of the bicycle according to the embodiment. In the figure, 13 is a main drive shaft, 32 is a front transmission, 33a, 33b are crank arms, 34 is a crankshaft, 50 to 52 are sun gears, 53 is a planetary gear train, 532
- 53c are gears with different diameters, 54 is a carrier, 54a is a fixed boss portion, 59 is a driven rotating body, 59a is an internal gear, 59
b is a driving side bevel gear, 59d is a main body part, 59e is a support boss part, 60 is a driven side bevel gear, 66 is a one-way clutch mechanism,
67 is a transmission mechanism.

Claims (1)

[Claims] (1) A crankshaft rotationally driven by crank arms on both sides, a carrier fixed to the crankshaft, a driven rotating body rotatably disposed around the crankshaft, and a plurality of driven rotors supported by the carrier. a planetary gear train having gears with different diameters; a plurality of sun gears meshing with each gear of the planetary gear train and rotatably arranged around the crankshaft;
an internal gear formed on the driven rotating body and meshing with any gear of the planetary gear train; a transmission mechanism that selectively fixes any of the sun gears; and a rotational force from the carrier to the driven rotating body. The input rotation of the crankshaft is changed at a predetermined gear ratio, and is extracted as the output rotation of the driven rotary body, which drives a drive shaft for driving the rear wheels. In the bicycle transmission device, a fixed boss portion is formed on the carrier in a cylindrical shape extending in the direction of the crankshaft, the crankshaft is inserted and fixed into the fixed boss portion, and the driven rotating body is formed into a substantially bowl-shaped fixed boss portion. It consists of a main body part and a cylindrical support boss part located at the axis of the main body part, and the support boss part is rotatably supported by the fixed boss part of the carrier, and the inner periphery of the main body part of the driven rotary body A bicycle transmission, characterized in that the internal gear is formed on a surface of the main body, and a driving bevel gear meshing with a driven bevel gear of the drive shaft is integrally formed on an outer surface of the main body.