TWM651763U - Crank device with labor-saving mechanism and bicycle crank assembly - Google Patents

Abstract

This new model relates to a crank device and a bicycle crank assembly with a labor-saving mechanism. The crank device includes a crank mechanism, a transmission mechanism, a support component and a swing arm component. The crank mechanism includes a crank, a shaft end gear and a pedal end gear; the transmission mechanism includes a rotating shaft. , the first gear and the second gear, annular grooves are provided at both ends of the rotating shaft; the support assembly is sleeved on the rotating shaft and includes an outer ring and balls. The balls are accommodated in the annular groove and are clamped between the rotating shaft and the outer ring respectively. between; the swing arm assembly includes a first swing arm and a second swing arm, one end of the second swing arm is connected to the first swing arm, and the other end of the second swing arm is connected to the pedal end gear. This can improve the stability of transmission and extend the service life.

Description

Crank device and bicycle crank assembly with labor-saving mechanism

The present invention relates to a bicycle crank device technology, in particular to a crank device with a labor-saving mechanism and a bicycle crank assembly.

As is known, the crank of a bicycle is a rod with a fixed length, which is used to connect the pedals to the central axis of the bicycle. During the operation of the bicycle, the user steps on the pedals so that the pedals rotate with the central axis as the center of rotation. The length of the crank is a circular motion of the radius, and drives the bicycle's driving device such as the gear wheel, chain and other components, thereby making the bicycle move forward.

The existing crank device widely used in bicycles cannot extend the crank arm to increase the length of the moment arm when the pedal rotates to the required force application position, so the effect of increasing the torque cannot be achieved. Perhaps some are designed using the telescopic characteristics of the crank. However, the design of such telescopic cranks is not ergonomic and cannot make a regular and inertial circular motion. It is essentially a laborious design. It is not only complex in structure but also easy to A pedal crank mechanism that causes user fatigue. In addition, some existing crank devices have problems such as insufficient structural strength, resulting in a short service life; and some problems such as difficulty in assembly and alignment, etc., all of which need to be overcome urgently.

In view of this, the author has devoted himself to research and applied academic theory to solve the above-mentioned problems in order to solve the above-mentioned deficiencies in the existing technology, which has become the goal of improvement of the author.

One purpose of the present invention is to provide a crank device and a bicycle crank assembly with a labor-saving mechanism, which can further optimize the overall structural strength, improve the stability of transmission and extend the service life.

In order to achieve the above purpose, the present invention provides a crank device with a labor-saving mechanism, including a crank mechanism, a transmission mechanism, a plurality of supporting components and a swing arm component. The crank mechanism includes a crank, a A shaft end gear and a pedal end gear provided at the other end of the crank; the transmission mechanism is provided inside the crank, the transmission mechanism includes a rotating shaft, a first gear and a second gear, the rotating shaft has a first end and a second end, the first gear is connected to the first end and meshes with the shaft end gear for transmission, the second gear connects the second end and meshes with the pedal end gear for transmission, between the first end and the shaft end gear The second ends are respectively provided with at least one annular groove; each of the support components is respectively sleeved on the first end and the second end of the rotating shaft. Each of the support components includes an outer ring and a plurality of balls. Each of the balls are accommodated in each of the annular grooves and are respectively clamped between the rotating shaft and each of the outer rings; the swing arm assembly includes a first swing arm and a second swing arm, and one end of the second swing arm is connected The other ends of the first swing arm and the second swing arm are connected to the pedal end gear.

In order to achieve the above purpose, the present invention provides a bicycle crank assembly. The bicycle has a central bearing socket. The crank assembly includes a central shaft, a set of crank devices and a set of adapter components. The central shaft is connected with the said central shaft. Each crank device is connected to one end of the central shaft; each adapter member is sleeved on each shaft end gear and is between each crank and the middle bearing seat.

This new type also has the following effects. The annular groove design of the rotating shaft can not only accommodate larger diameter balls, but also increase the thickness of the outer ring, which can double the strength and service life. The opening design of the positioning ring facilitates torsional deformation of the positioning ring and is sleeved on the rotating shaft, and is pushed into the outer ring to be fixed. Through the arrangement of each resisting wall, the axial thrust in the up and down directions of the rotating shaft is eliminated, making the operation of the transmission mechanism more stable. When the pedal is stepped on to make the crank move in a circular motion, there are no problems with the upper and lower dead centers and transmission problems such as stumbling. With the help of the transmission of helical gears and bevel gears, close contact can be achieved regardless of whether the crank is rotating in the forward or reverse direction, thereby reducing the generation of noise and improving the transmission efficiency and positioning accuracy.

1: Crank device

10:Crank mechanism

11:Crank

111:Outer shell

111A: Edge-sealing peripheral board

112:Cylindrical column

113:First connection hole

114:Riveted column

115:Toothed hole

116:Inner shell

116A: Inner edge surface of edge sealing

1161:Socket hole

117: Second connector

118: sleeve hole

119:Protruding pillar

12:Shaft end gear

121:Inner bushing

122: Helical gear

1221: Groove

123:Ball bearing

13:Pedal end gear

131: Bushing

132:Front ball bearing

133: Rear ball bearing

134:Helical gear

1341:Card

20: Transmission mechanism

21:Rotating axis

211:First end

212:Second end

213: Annular ditch

22:First gear

23: Second gear

30:Support component

31: Outer ring

32: Ball

33: Positioning ring

331: Bottom circle

332:Rongzhu Department

333:Open your mouth

40: Swing arm assembly

41:First spiral arm

411:Pedal receiving column

412:Socket slot

413:Insert block

42:Second spiral arm

421:Through hole

422: Embed block

423: Accepting slot

424:Stud

425:Card slot

A: Clamp half part

B: Another clamping shaft half part

C: Upper stop wall

D: Lower stop wall

5: Central axis

51:Spindle section

52:Extended section

521:Tooth column

522:Screw hole

53:bolt

6. 6A: Transfer component

61:joint parts

611: Ring body

612:Connecting arm

613: Cuttings

614:External inserts

615:Insert strip

62: hitting the pole

63:Screw components

7:Sprocket assembly

71:Sprocket

72:Fixed bracket

721:Perforation

8:Bicycle

81: Frame

82: Center bearing socket

821:Slot

83:Left fork tube

84:Right fork tube

85:Riser

86: Foot pedal

87: embedded ring

Figure 1 is an exploded view of the new crank device with a labor-saving mechanism.

Figure 2 is an exploded view of the new shaft end gear.

Figure 3 is an exploded view of the pedal end gear of the present invention.

Figure 4 is an exploded view of the transmission mechanism of this new type.

Figure 5 is an exploded view of the new support assembly.

Figure 6 is an exploded view of the swing arm assembly of this new type.

Figure 7 is an assembled cross-sectional view of the new crank device with a labor-saving mechanism.

Figure 8 is an exploded view of the new bicycle crank assembly and bicycle frame.

Figure 9 is an exploded view of the crank device and stop components of this new type of labor-saving mechanism.

Figure 10 is a cross-sectional view of the combination of the new bicycle crank assembly and the bicycle frame.

Figure 11 is an appearance view of the new crank assembly combined with the bicycle frame.

Figure 12 is a combination diagram of the new crank assembly applied to a bicycle.

Figure 13 is a diagram of the use status of the new bicycle crank assembly.

Figure 14 is an exploded view of another embodiment of the new adapter component and the bicycle frame.

Figure 15 is a combined sectional view of Figure 14.

The detailed description and technical content of the present invention are described below with reference to the drawings. However, the attached drawings are only for reference and illustration and are not intended to limit the present invention.

Referring to FIGS. 1 to 7 , the present invention provides a crank device with a labor-saving mechanism. The crank device 1 mainly includes a crank mechanism 10 , a transmission mechanism 20 , a plurality of support components 30 and a swing arm component 40 .

Please refer to Figures 1 to 3 first. The crank mechanism 10 mainly includes a crank 11, a shaft end gear 12 and a pedal end gear 13. The crank 11 of this embodiment mainly includes an outer shell 111 and an inner shell 116. A cylindrical column 112 extends from the upper end of the outer casing 111, and a first connecting hole 113 is provided at the lower end. A clamping shaft half part A is provided between the cylindrical column 112 and the first connecting hole 113 inside the outer casing 111. ; Furthermore, a plurality of evenly distributed riveting columns 114 are provided on the inner periphery of the outer shell 111; further, a toothed hole 115 is formed inside the cylindrical column 112.

The shape of the inner housing 116 corresponds to the shape of the outer housing 111. A second connection hole 117 is provided at the upper end of the inner housing 116, and a sleeve hole 118 is provided at the lower end of the inner housing 116. The sleeve hole 118 is Corresponding to the aforementioned first connecting hole 113, and extending between the second connecting hole 117 and the sleeve hole 118 inside the inner housing 116, there is another clamping shaft half-part B. This other clamping shaft half-part B It is configured corresponding to the aforementioned clamping shaft half part A.

The shaft-end gear 12 is a static gear (that is, it is fixed and does not rotate). It is sleeved on the cylindrical column 112 and then passed through the second connecting hole 117, so that the shaft-end gear 12 is supported on the cylindrical column 112 and the inner shell. between bodies 116 (as shown in Figure 7). As shown in Figure 2, the shaft end gear 12 mainly includes an inner bushing 121, a helical gear 122 and A ball bearing 123, in which the inner bushing 121 is sleeved on the aforementioned cylindrical column 112, the helical gear 122 is sleeved on the inner bushing 121, and the ball bearing 123 is sleeved on the helical gear 122 and is supported by the inner shell 116 and the helical gear. The gears 122 are clamped together. The helical gear 122 is provided with a plurality of slots 1221, and each slot 1221 is arranged at equal intervals.

The pedal end gear 13 is a moving gear (that is, it is driven by the transmission mechanism 20 to rotate during the rotation of the crank 11), which is straddled between the first connecting hole 113 and the sleeve hole 118, so that the pedal The end gear 13 is supported at the lower ends of the outer housing 111 and the inner housing 116 (see Figure 7). As shown in Figure 3, the pedal end gear 13 mainly includes a sleeve 131, a front ball bearing 132, a rear ball bearing 133 and a helical gear 134. The sleeve 131 is connected corresponding to the sleeve hole 118, and the front ball bearing 132 is connected Connected to one end of the sleeve 131 and accommodated in the sleeve hole 118, the helical gear 134 is sleeved on the other end of the sleeve 131, and the rear ball bearing 133 is sleeved on the helical gear 134 and is supported by the outer housing 111 and the helical gear. 134 are clamped together (as shown in Figure 7).

Please refer to Figures 4 and 5 together. The transmission mechanism 20 is disposed inside the crank 11 and mainly includes a rotating shaft 21, a first gear 22 and a second gear 23. The rotating shaft 21, the first gear 22 The first gear 22 and the second gear 23 are both bevel helical gears. The rotating shaft 21 has a first end 211 and a second end 212 away from the first end 211. The first gear 22 extends from the first end 211 and meshes with the shaft end gear 12 for transmission, and the second gear 23 extends from the second end 211. The end 212 extends and meshes with the pedal end gear 13 for transmission. A plurality of annular grooves 213 are respectively provided at the first end 211 and the second end 212. The annular grooves 213 can also be designed as a single number.

Each supporting component 30 is respectively sleeved on the first end 211 and the second end 212 of the rotating shaft 21 . As shown in Figure 5, each support component 30 mainly includes an outer ring 31, a plurality of balls 32 and a positioning ring 33. Each ball 32 is partially accommodated in the annular groove 213 and is respectively surrounded by the outer ring 31. , the positioning ring 33 is installed in the outer ring 31 and is used to separate and position each ball 32. The positioning ring 33 mainly includes It includes a bottom ring 331 and a plurality of bead-containing parts 332 extending upward from the bottom ring 331. Each bead-containing part 332 is arranged at equal intervals and accommodates each ball 32 respectively. The bottom ring 331 is provided with an opening 333, which is mainly It is used to provide the positioning ring 33 to produce torsional deformation and be sleeved on the rotating shaft 21 , and be pushed into the outer ring 31 to be fixed. In one embodiment, the inner diameter of the outer ring 31 is larger than the outer diameter of one of the first gear 22 and the second gear 23 to facilitate assembly and installation.

In one embodiment, in addition to being solely provided on the first end 211 and the second end 212 of the rotating shaft 21 , the supporting components 30 can also be stacked on top of each other and then respectively provided on the first end 211 and the second end 211 of the rotating shaft 21 . Second end 212.

Please refer to FIG. 1 again. In one embodiment, the clamping shaft half A of the outer housing 111 and the other clamping half B of the inner housing 116 jointly clamp each supporting assembly 30 and the rotating shaft 21. The upper ends of the clamping shaft half A of the outer shell 111 and the other clamping half B of the inner shell 116 are commonly surrounded by an upper stop wall C (as shown in Figure 7). Half part A and the lower end of the other clamping shaft half part B of the inner shell 116 are jointly surrounded by a lower stop wall D (as shown in Figure 7 ), and each upper support component 30 is attached to the upper stop wall C , the supporting components 30 below are in contact with the lower resisting wall D, thereby eliminating the axial thrust in the up and down directions of the rotating shaft 21 and making the operation of the transmission mechanism 20 more stable.

As shown in FIG. 1 , in one embodiment, the outer shell 111 is formed with a sealing peripheral plate 111A on its periphery, and the inner shell 116 is formed with a sealing inner edge surface 116A corresponding to the periphery of the outer shell 111 . The inner shell 116 is provided with a plurality of socket holes 1161 corresponding to each of the aforementioned riveting posts 114, in which the edge-sealing peripheral plate 111A is socketed corresponding to the edge-sealing inner edge surface 116A, and each riveting post 114 has a respective socket hole. 1161, and through a sealing and riveting process, the outer shell 111 and the inner shell 116 are tightly connected and fixed (as shown in Figure 7).

Please continue to refer to Figure 6. The swing arm assembly 40 includes a first swing arm 41 and a second swing arm 42. The first swing arm 41 and the second swing arm 42 are both arc-shaped swing arms. The first swing arm 41 is It is formed between the crank 11 and the second swing arm 42, and is provided with a pedal receiving column 411, and is provided with a socket groove 412 and an inserting block 413 at an end away from the pedal receiving column 411. The second swing arm 42 is provided with a through hole 421, and is provided with an embedded block 422 and a receiving groove 423 at an end away from the through hole 421; the pedal receiving column 411 is provided with the aforementioned through hole 421, the receiving groove 423 and the embedded block 422. Then the inserting block 413 and the socket groove 412 respectively corresponding to the first swing arm 41 are combined.

In one embodiment, a stud 424 is provided on the side of the through hole 421 of the second swing arm 42 and a plurality of clamping grooves 425 are formed around the outer periphery of the stud 424. The helical gear 134 is provided with a plurality of clamping strips 1341; The column 424 is connected to the aforementioned helical gear 134, and each clip 1341 is inserted into each clip slot 425 respectively. A bolt is penetrated from the outside of the inner housing 116 and connected through the shaft sleeve 131 corresponding to the stud 424.

Referring to FIGS. 8 to 11 , the present invention also provides a bicycle crank assembly, which mainly includes a central shaft 5 , a set of crank devices 1 and a set of adapter components 6 .

The central axis 5 mainly includes a main shaft section 51 and an extension section 52 extending outward respectively from both ends of the main shaft section 51. The extension section 52 is provided with a toothed column 521 for the aforementioned cylindrical column 112 to use its toothed hole. 115 are sleeved together, and a screw hole 522 is provided on the end surface of the extension section 52 for a bolt 53 to pass through and lock.

Each adapter member 6 mainly includes a connecting member 61 and a resisting rod 62. Each connecting member 61 mainly includes a ring body 611 and a connecting arm 612 extending from the ring body 611. One side of the ring body 611 is provided with an embedded Ring, the other side of the ring body 611 is provided with a plurality of inserts 613, the resisting rods 62 are locked through a screw element 63 passing through the connecting arm 612, and the resisting rods 62 are connected and locked with each other.

In one embodiment, the new bicycle crank assembly also includes a sprocket assembly 7, which is sleeved on the inner shell 116 of one of the cranks 11. The sprocket assembly 7 mainly includes a sprocket 71 and a fixed Frame 72, the fixed frame 72 is locked on the sprocket 71 through screw elements such as bolts, and the fixed frame 72 is sleeved on the inner shell 116 of the aforementioned crank 11. In addition, the fixed frame 72 is provided with a through hole 721 on the inside. The housing 116 extends with a protruding column 119 , and the protruding column 119 is connected with the through hole 721 , so that the crank 11 can drive the sprocket assembly 7 to rotate.

The present invention is mainly applied to a bicycle 8. The bicycle 8 has a frame 81, a middle bearing socket 82 is installed below the frame 81, and a left fork tube extends from the middle bearing socket 82 toward the rear wheel. 83. A right fork tube 84 is formed on the right side of the left fork tube 83 and a riser tube 85 extends upward; in addition, the bicycle 8 also includes a set of pedals 86, a set of embedded rings 87 and other necessary devices.

During assembly, the central axis 5 is inserted into the central bearing socket 82, and each embedded ring 87 is locked in the central bearing socket 82, and the central axis 5 is confined in the central bearing socket 82, in which the main shaft section 51 of the central axis 5 can It performs rotational motion in the middle bearing seat 82. First, the embedding rings of each adapter member 6 are embedded and positioned corresponding to each embedding ring 87, so that each adapter member 6 is formed on both sides of the middle bearing seat 82, and the resisting rod 62 of the adapter member 6 on the left side is The connecting rods 62 are connected to the right adapter member 6 , and the connected supporting rods 62 are pressed against the rear side of the riser 85 . Then, the toothed hole 115 of the cylindrical column 112 is aligned with the toothed column 521 of the central shaft 5 for sleeve connection, and at the same time, each insert 613 of the ring body 611 is inserted into each slot 1221 of the shaft end gear 12. Finally, a bolt 53 is inserted into the cylindrical column 112 of the crank 11 and locked corresponding to the screw hole 522 of the central axis 5, so that the rotation of each crank 11 can drive the central axis 5 to rotate.

Please refer to Figures 12 and 13 for further explanation. Since a force-applying arm from the axis center of the shaft end gear 12 to the connection between the first swing arm 41 and the second swing arm 42 is longer than the length of the crank 11, according to The principle of torque (M=F*d, F: action force, d: moment arm), so when the moment is the same, increasing the length of the moment arm will reduce the applied force.

During operation, by exerting force on the foot pedal 86, the crank mechanism 10 drives the central shaft 5 and the sprocket assembly 7 to rotate along with each crank 11 through the cylindrical column 112. When the swing arm assembly 40 rotates downward from the apex position, through the third A gear 22 is driven by the shaft end gear 12, thereby driving the rotating shaft 21 and the second gear 23 to rotate. The second gear 23 drives the pedal end gear 13 to rotate, thereby maintaining a constant angle between the arm assembly 40 and the ground, and The motion trajectory of the center point of the foot pedal 86 forms a nearly circular motion. In addition, the movement direction of the swing arm assembly 40 is opposite to the movement direction of the crank 11 .

Please refer to Figures 14 and 15. In addition to the above embodiment, the new bicycle crank assembly of the present embodiment is provided with a plurality of slots 821 on both sides of the middle bearing socket 82. The adapter member 6A mainly includes A ring body 611, a plurality of outer insert strips 614 extending from the outer circumferential surface of the ring body 611, and a plurality of inner insert strips 615 extending from the inner circumferential wall of the ring body 611, each outer insert strip 614 corresponding to each slot of the middle bearing socket 82 821 is embedded and combined, and the inner insert strip 615 is embedded and combined corresponding to each of the embedded grooves 1221 of the helical gear 122 of the shaft end gear 12, which also has the same effect as the previous embodiment.

The above descriptions are only preferred embodiments of the present invention and are not intended to define the patent scope of the present invention. Other equivalent changes that apply the patent spirit of the present invention should all fall within the patent scope of the present invention.

1: Crank device

10:Crank mechanism

11:Crank

111:Outer shell

111A: Edge-sealing peripheral board

112:Cylindrical column

113:First connection hole

114:Riveted column

115:Toothed hole

116:Inner shell

116A: Inner edge surface of edge sealing

1161:Socket hole

117: Second connector

118: sleeve hole

12:Shaft end gear

13:Pedal end gear

20: Transmission mechanism

21:Rotating axis

22:First gear

23: Second gear

30:Support component

40: Swing arm assembly

41:First spiral arm

42:Second spiral arm

A: Clamp half part

B: Another clamping shaft half part

C: Upper stop wall

D: Lower stop wall

Claims (12)

A crank device with a labor-saving mechanism consisting of: A crank mechanism includes a crank, a shaft end gear provided at one end of the crank, and a pedal end gear provided at the other end of the crank; A transmission mechanism is provided inside the crank. The transmission mechanism includes a rotating shaft, a first gear and a second gear. The rotating shaft has a first end and a second end, and the first gear is connected to the first end. And meshed with the shaft end gear for transmission, the second gear is connected to the second end and meshed with the pedal end gear for transmission, and at least one annular groove is provided at the first end and the second end respectively; A plurality of support components are respectively sleeved on the first end and the second end of the rotating shaft. Each support component includes an outer ring and a plurality of balls. Each ball is accommodated in each annular groove and is clamped respectively. held between the shaft and each outer ring; and A swing arm assembly includes a first swing arm and a second swing arm. One end of the second swing arm is connected to the first swing arm, and the other end of the second swing arm is connected to the pedal end gear. The crank device with a labor-saving mechanism as claimed in claim 1, wherein each of the support components further includes a positioning ring, which is installed in the outer ring and used to separate and position each of the balls. The crank device with a labor-saving mechanism as claimed in claim 2, wherein the positioning ring includes a bottom ring and a plurality of ball-containing portions extending from the bottom ring, and each ball is disposed corresponding to each bead-containing portion. The bottom ring is provided with an opening. The crank device with a labor-saving mechanism as claimed in claim 1, wherein the rotating shaft, the first gear and the second gear are integrally formed. The crank device with a labor-saving mechanism as claimed in claim 1, wherein the shaft-end gear includes an inner bushing, a helical gear and a ball bearing, and the crank includes an outer shell and an assembly corresponding to the outer shell. The inner shell has a cylindrical column, the inner lining sleeve is sleeved on the cylindrical column, the helical gear is sleeved on the inner liner sleeve, and the ball bearing is sleeved on the helical gear and is supported by the inner shell. and the helical gear are clamped together. The crank device with a labor-saving mechanism as claimed in claim 1, wherein the crank includes an outer shell and an inner shell assembled corresponding to the outer shell. The outer shell is provided with a shaft clamping half part, and the inner shell is Another clamping shaft half-part is provided inside the housing. The other clamping shaft half-part is arranged corresponding to the clamping shaft half-part and jointly clamps each of the supporting components and the rotating shaft. The crank device with a labor-saving mechanism as claimed in claim 6, wherein an upper stop wall is commonly surrounded by the upper ends of the clamping shaft half part of the outer housing and the other clamping shaft half part of the inner housing, A lower end of the clamping shaft half part of the outer shell and the other clamping shaft half part of the inner shell are collectively surrounded by a lower stop wall, and a part of the support assembly is attached to the upper stop wall, and the other part is attached to the upper stop wall. A part of the supporting component is attached to the lower resisting wall. The crank device with a labor-saving mechanism as claimed in claim 1, wherein the crank includes an outer housing and an inner housing, and the pedal end gear includes a sleeve, a front ball bearing, a rear ball bearing and a helical gear, The inner shell is provided with a set hole, and the shaft sleeve is penetrated correspondingly to the set hole. The front ball bearing is sleeved on one end of the shaft sleeve and is accommodated in the set hole. The helical gear is sleeved in At the other end of the sleeve, the rear ball bearing is sleeved on the helical gear and is jointly held by the outer housing and the helical gear. The crank device with a labor-saving mechanism as described in claim 1, wherein the crank includes an outer shell and an inner shell, the outer shell is provided with a sealing edge peripheral plate and a plurality of riveting posts, and the inner shell is provided with a sealing edge. The inner edge surface of the edge and a plurality of socket holes, the edge sealing peripheral plate is socketed corresponding to the edge sealing inner edge surface, and each riveting column is respectively penetrated with each socket hole, and is processed through a sealing and riveting process. The outer shell and the inner shell are bonded. A bicycle crank assembly, the bicycle has a central bearing socket, the crank assembly includes: A central axis is connected to the central bearing socket; A set of crank devices as described in any one of claims 1 to 9, each crank device being connected to one end of the bottom bracket; and A set of adapter members, each adapter member is sleeved on each shaft end gear and is between each crank and the middle bearing seat. The bicycle crank assembly according to claim 10, the bicycle further has a riser connected to the middle bearing socket, each adapter member includes a joint and a butt bar, the joint includes a ring body and an automatic A connecting arm extends from the ring body, and each of the resisting rods is locked to each connecting arm through a screw element, and each of the resisting rods is connected to each other and abuts against the riser. The bicycle crank assembly according to claim 10, wherein the middle bearing seat is provided with a plurality of slots, the shaft end gear is provided with a plurality of inserting grooves, and each of the adapter members includes a ring body, from the outer peripheral surface of the ring A plurality of extended outer inserting strips and a plurality of inner inserting strips extending from the inner peripheral wall of the ring, each of the outer inserting strips is embedded and combined corresponding to each of the said slots, and each of the inner inserting strips is embedded in corresponding to each of the said slots. combine.

Images