Internal fixed-axis transmission for bicycle

Abstract

The present invention provides an internal fixed-axis transmission for a bicycle, comprising: a first transmission part, a second transmission part and a driving body, wherein the first transmission part comprises a first rotating body, a second rotating body and a first fixed axis for supporting the first rotating body, and the first rotating body can be transmission-connected with the second rotating body during movement; the second transmission part comprises a third rotating body transmission-connected with the first rotating body and a fourth rotating body transmission-connected with the second rotating body; the driving body is used to transmit human driving force to the first rotating body; the first transmission part also comprises a fifth rotating body transmission-connected with the third rotating body and a sixth rotating body transmission-connected with the fourth rotating body. The present invention takes the fixed-axis speed change gear train composed of the first transmission part, the second transmission part and the driving body as the main body, and can increase the gear module while meeting the external dimensions, so that the bending strength is greatly enhanced, and the service life of the transmission is increased.

Description

Technical Field

[0001] The invention belongs to the technical field of bicycle speed changing equipment, and in particular relates to an internal fixed-shaft speed changer for a bicycle. Background Art

[0002] The emergence of bicycles has greatly facilitated people's travel. With the improvement of production technology, the development of science and technology and humanistic spirit, people have higher requirements for bicycles. The design and manufacture of bicycles are constantly improving, their structure and technology are becoming more and more reasonable, and their performance is also constantly improving. With the emergence of bicycles, variable-speed bicycles have also begun to develop. At present, the transmission of bicycles is roughly divided into two categories: tower wheel type external transmission and closed internal transmission. The external transmission is to install sprockets with different numbers of teeth on the rear wheel of the bicycle, and rely on the chain to cooperate with different sprockets to achieve the change of transmission ratio. However, the external transmission is exposed to the outside of the bicycle and is easily corroded by rain, dust, and grease, making maintenance more cumbersome, the service life is short, and the appearance is not very beautiful. The internal transmission speed change device is hidden inside the shaft barrel and is protected by multiple layers of special sealing materials to avoid exposure to the outside world. Therefore, rain, dust, grease, etc. cannot enter, and it also avoids the sun's exposure and wind and rain erosion. Therefore, regular maintenance is not required, achieving the advantages of maintenance-free, precision, durability, and lightness.

[0003] The existing three-speed transmission in bicycles is mainly based on planetary gear trains. Due to its structural design, the speed-up ratio must be less than 2 and the speed-down ratio must be greater than 0.5 in theory. In actual production, the transmission ratio is limited to a greater extent under the premise of ensuring cost and performance. The speed-up ratio can only be 1.4 and the speed-down ratio can only be 0.7. The consequence is that the speed-up feeling is not strong when speeding up, climbing is difficult at low speed, and the acceleration and deceleration feeling is not obvious when riding. Summary of the invention

[0004] The object of the present invention is to provide a bicycle internal fixed axis transmission with a larger transmission ratio and higher strength.

[0005] In order to achieve the above-mentioned object, the technical solution adopted by the present invention is: an internal fixed-axis transmission for a bicycle, comprising: a first transmission part, comprising a first rotating body, a second rotating body, and a first fixed axis that can rotate and support the first rotating body, the first rotating body can move axially on the first fixed axis, and can achieve transmission connection with the second rotating body during the movement, and the second rotating body rotates coaxially with the first rotating body;

[0006] The second transmission part includes a third rotating body drivingly connected to the first rotating body and a fourth rotating body drivingly connected to the second rotating body, the third rotating body can rotate around the second fixed axis, the first fixed axis and the second fixed axis are arranged in parallel and are relatively stationary;

[0007] A driving body, which rotates around a first fixed axis and is used to transmit a human driving force to the first rotating body;

[0008] The first transmission part further includes a fifth rotating body drivingly connected to the third rotating body and a sixth rotating body drivingly connected to the fourth rotating body, and both the fifth rotating body and the sixth rotating body rotate around the first fixed axis.

[0009] Furthermore, the first rotating body and the second rotating body are connected in transmission by mutually matching concave parts and convex parts.

[0010] Furthermore, the rotation axis of the fourth rotating body is parallel to or coincides with the central axis of the second fixed shaft.

[0011] Furthermore, a first overrunning clutch is arranged between the fifth rotating body and the sixth rotating body.

[0012] Furthermore, a second overrunning clutch is arranged between the sixth rotating body and the housing.

[0013] Furthermore, the fixed-axis transmission also includes a housing and a connecting component installed on the driving body and used to connect the driving body and the housing. A convex surface for separating the driving body from the housing is provided on the first rotating body. When the first rotating body moves on the first fixed axis, if the convex surface on the first rotating body contacts the connecting component, the driving body is separated from the housing.

[0014] Furthermore, the shell is provided with a concave portion or a convex portion matching the connecting component.

[0015] Furthermore, the first transmission part, the second transmission part, the driving body and the connecting component are all arranged in the shell.

[0016] Furthermore, the first fixed shaft is also provided with a guide portion for guiding the first rotating body to move axially on the first fixed shaft.

[0017] Compared with the prior art, the beneficial effects of the present invention are: the present invention, which takes the fixed-axis speed-changing gear train composed of the first transmission part, the second transmission part and the driving body as the main body, can increase the gear module while meeting the external dimensions, greatly enhance the bending strength, and increase the service life of the transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The present invention is a schematic diagram of the overall structure of an internal fixed-axis transmission for a bicycle;

[0019] Figure 2 The present invention is a disassembled stereoscopic diagram of an internal fixed-axis transmission for a bicycle;

[0020] Figure 3The present invention is a disassembled stereoscopic view of a first transmission part of an internal fixed-axis transmission for a bicycle;

[0021] Figure 4 The invention is a schematic diagram of the connection relationship between the first rotating body and the guide part in the internal fixed-axis transmission for a bicycle;

[0022] Figure 5 The present invention is a disassembled stereoscopic view of a fifth rotating body and a sixth rotating body in an internal fixed-axis transmission for a bicycle;

[0023] Figure 6 The present invention is a disassembled stereoscopic view of a second transmission part of an internal fixed-axis transmission for a bicycle;

[0024] Figure 7 The invention discloses a schematic diagram of the connection relationship between a driving body and a connecting component in an internal fixed-axis transmission for a bicycle. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0026] See also Figure 1 and Figure 2 A bicycle internal fixed-axis transmission comprises: a left fastener 2, a left dust cover 1, a right fastener 6, a right dust cover 4, a first transmission part 8, a second transmission part 9, a connecting part 5, a driving body 7, a guide part and a housing 3.

[0027] See also Figure 3 and Figure 6 The second transmission unit 9 includes a rotating body base 95 , a third rotating body 93 and a fourth rotating body 94 .

[0028] The rotating body base 95 is connected to the first fixed axis by a key to limit its radial rotation. A first elastic retaining ring 88 is provided on the side of the rotating body base to limit the axial movement of the rotating body base 95 along the first fixed axis.

[0029] See also Figure 6The third rotating body 93 is composed of a third gear shaft 931, a third gear 932 and a third circlip 933. The number of teeth of the gear 93101 on the third gear shaft is greater than the number of teeth of the third gear 932. The third gear 932 is connected to the third gear shaft 931 through a special-shaped shaft, which limits the radial rotation of the third gear 932 around the third gear shaft 931. A third circlip 933 is provided at the first end 93102 of the third gear shaft to prevent the third gear 932 from moving along the axial direction of the third gear shaft 931, so that the third gear shaft 931 and the third gear 932 remain stationary.

[0030] See also Figure 6 The fourth rotating body 94 is composed of a fourth gear shaft 941, a fourth gear 943 and a fourth elastic retaining ring 942. The number of teeth of the gear 94101 on the fourth gear shaft is less than the number of teeth of the fourth gear 943. A plane 94102 is set on the fourth gear shaft. The plane 94102 connects the tooth side surfaces of the gear 94101 on the gear shaft, which can increase the bending strength of the gear. The fourth gear 943 is connected to the fourth gear shaft 941 through a special-shaped shaft to limit the radial rotation of the fourth gear 943 around the fourth gear shaft 941. A fourth retaining ring 942 is set on the first side surface 94301 of the fourth gear 943 to prevent the fourth gear 943 from moving axially along the fourth gear shaft 941, so that the fourth gear shaft 941 and the fourth gear 943 remain stationary.

[0031] The fourth gear shaft 941 is configured as a hollow structure, so that the third gear shaft 931 can pass through the hollow 94104 and be connected therewith, so that the third rotating body 93 and the fourth rotating body 94 can rotate coaxially, and as many second transmission parts as possible can be arranged on the rotating body base 95, so that the torque shared by each rotating body is reduced, and the service life of the transmission is extended. A hole 9501 is provided on the rotating body base, and the hole 9501 is connected with the fourth gear shaft 941.

[0032] The first side surface 94105 of the gear on the fourth gear shaft 941 contacts the first side surface 95102 of the rotating body base 95, and the second side surface 94302 of the fourth gear 943 contacts the second side surface 95103 of the rotating body base, so that the fourth gear shaft 941 and the fourth gear 943 remain relatively stationary with the rotating body base 95 in the axial direction of the fourth gear shaft 941. The first side surface 93103 of the gear on the third gear shaft contacts the first end surface 94105 of the fourth gear shaft, and the third shaft sleeve 96 is provided on the third gear shaft 931. The first end surface 9601 of the third shaft sleeve contacts the second end surface 94103 of the gear on the fourth gear shaft, and the second end surface 9602 of the third shaft sleeve contacts the first side surface 93201 of the third gear. In this way, the third rotating body 93 remains relatively stationary with the fourth rotating body 94 in the axial direction.

[0033] See also Figure 3The first transmission part 8 includes a first rotating body 81 , a second rotating body 82 , a fifth rotating body 85 and a sixth rotating body 86 .

[0034] The first side surface 8201 of the second rotating body 82 contacts the second side surface 8702 of the first fixed shaft, and the second side surface 8202 of the second rotating body 82 contacts the gear plane 94102 on the fourth gear shaft, so the second rotating body 82 is stationary in the axial direction of the first fixed shaft. A first convex portion 8203 is provided on the second side surface 8202 of the second rotating body, and a second convex portion 81101 is provided on the first rotating body 81. The two are connected under the action of the push spring 815. After the connection, the movement of the first rotating body 81 can be transmitted to the second rotating body 82.

[0035] The first rotating body 81 includes a first gear shaft 811, a control trigger 812, an elastic retaining ring 814 and a retaining ring 813. The first gear shaft 811 is a hollow structure, the first fixed shaft cooperates with the hollow inner side surface 81102 of the first gear shaft, the first gear shaft 811 rotates around the first fixed shaft, the inner side surface of the control trigger 812 has an inner tooth surface 81201 that cooperates with the outer tooth surface 81103 of the first gear shaft, the outer tooth surface 81103 of the first gear shaft contacts the inner tooth surface 81201, and the first gear shaft 811 is relatively stationary in the radial direction with the control trigger 812, and a second elastic retaining ring 814 is provided at the second end 81104 of the first gear. A retaining ring 813 is arranged between the elastic retaining ring 814 and the control trigger member 812, and the second side surface 81302 of the retaining ring contacts the second elastic retaining ring 814, and the first side surface 81301 of the second elastic retaining ring 814 contacts the second side surface 81202 of the control trigger member. Therefore, the first gear shaft 811 and the control trigger member 812 are relatively stationary in the axial direction, and a return spring 815 is arranged between the retaining ring 813 and the first fastener 6. The return spring 815 pushes the retaining ring 813 to move the first rotating body 81 along the fixed axis toward the second rotating body 82.

[0036] A fifth rotating body 85 and a sixth rotating body 86 are provided at the other end of the first transmission part 8. Figure 5 The sixth rotating body 86 includes a sixth gear shaft 861, a sixth elastic retaining ring 863 and a chuck 862. The sixth gear shaft 861 is a hollow structure, the hollow inner side surface 86101 of the sixth gear shaft cooperates with the first fixed shaft and rotates around the first fixed shaft, the first end surface 86102 of the sixth gear shaft contacts the side surface of the second fastener 2, so that the sixth gear shaft 861 and the first fixed shaft are relatively stationary in the axial direction, the first end 86103 of the sixth gear shaft is connected to the chuck 862 through a special-shaped shaft, limiting the radial rotation of the chuck 862 relative to the sixth gear shaft 861, and the first end 86103 of the sixth gear shaft is provided with a sixth elastic retaining ring 863 to limit the axial movement of the chuck 862, so that the chuck 862 and the sixth gear shaft 861 are relatively stationary.

[0037] The fifth rotating body 85 is a hollow structure. The hollow inner side surface 8501 of the fifth rotating body cooperates with the outer side surface 86104 of the sixth rotating body. The fifth rotating body 85 can rotate relative to the sixth rotating body 86. The fifth gear side surface 85102 on the fifth rotating body contacts the first side surface 86105 of the gear on the sixth gear shaft. The side surface 85103 of the fifth rotating body contacts the side surface 86201 of the chuck. The fifth rotating body 85 and the sixth rotating body 86 are relatively stationary in the axial direction.

[0038] A first clamping claw 85104 is provided in the circumferential direction of the fifth rotating body 85, a first clamping groove 86202 is provided on the inner side of the chuck 862, and the first clamping claw 85104 is meshed with the first clamping groove 86202, so that a one-way clutch structure is formed between the first clamping claw 85104 and the first clamping groove 86202. A second clamping claw 86203 is provided on the outer side of the chuck 862, a second clamping groove 32 is provided on the inner side of the second end 31 of the housing, and the second clamping claw 86203 is meshed with the second clamping groove 32, so that a one-way clutch structure is formed between the second clamping claw 86203 and the second clamping groove 32.

[0039] See also Figure 4 The guide portion includes a convex portion 81203 on the control trigger member and a concave portion 7401 on the inner side of the driving body corresponding to the convex portion. The convex portion 81203 on the control trigger member contacts the concave portion 7401 on the inner side of the driving body. The control trigger member 812 moves axially along the first fixed axis. The control trigger member 812 and the driving body 7 are relatively stationary in the radial direction, but can move relatively in the axial direction. When shifting gears, the driving body 7 can still transmit power to the first rotating body 81 through the guide portion.

[0040] See also Figure 7A gap 7402 for accommodating a connecting component is provided on the driving body 7. The rotating shaft 71 passes through the gap 7402 and is fixed to the driving body 7. The hole 7301 on the connecting component cooperates with the rotating shaft 71. The connecting component 73 rotates around the rotating shaft 71. This can balance the force on the driving body 7 and make the power transmission more stable. A return spring 72 is arranged between the first side surface 7302 of the connecting component and the first side surface 7403 of the gap, one end of the return spring is fixed to the connecting component 73, and the other end is fixed to the driving body 7. The return spring 72 makes the first end 7302 of the connecting component approach the third card slot 33 close to the second end of the shell, so that the driving body 7 is connected to the shell 3. A convex surface 81204 and an inclined surface 81205 are arranged on the control trigger 812, and an inclined surface 7305 is arranged on the second end 7304 of the connecting component to correspond to the inclined surface 81205 on the control trigger component, so that the convex surface 81204 on the control trigger component can smoothly act on the second end 7304 of the connecting component. When the convex surface 81204 on the control trigger component contacts the second end 7304 of the connecting component, the first end 7303 of the connecting component is away from the third card slot 33 on the shell, and the driving body 7 is not connected to the shell 3.

[0041] When the first rotating body 81 is connected to the second rotating body 82, the convex surface 81204 on the control trigger member of the first rotating body 81 does not contact the second end 7304 of the connecting component. At this time, the first end 7303 of the connecting component contacts the third slot 33 on the shell, and the driving body 7 is connected to the shell 3. The first rotating body 81 decelerates and transmits the motion to the fifth rotating body 85 through the second transmission part 9, and the second rotating body 82 accelerates and transmits the motion to the sixth rotating body 86 through the second transmission part 9. At this time, the rotation speed of the sixth rotating body 86 is greater than that of the fifth rotating body 85, and the motion is transmitted to the shell 3 through the second claw 86203. Since the rotation speed of the sixth rotating body 86 is greater than the rotation speed of the driving body 7, the connection between the connecting component 73 and the shell 3 does not transmit motion. At this time, the rotation speed of the shell 3 is the same as the rotation speed of the sixth rotating body 86, which is accelerated.

[0042] When the first rotating body 81 moves in the direction away from the second rotating body 82, the first rotating body 81 is not connected to the second rotating body 82, and the convex surface 81204 on the control trigger member of the first rotating body is not in contact with the second end 7304 of the connecting component. At this time, the first end 7303 of the connecting component is in contact with the third slot 33 on the shell, and the driving body 7 is connected to the shell 3. The first rotating body 81 decelerates and transmits the motion to the fifth rotating body 85 through the second transmission part 9, and the fifth rotating body 85 transmits the motion to the sixth rotating body 86 through the first claw 85104. The sixth rotating body 86 is connected to the shell 3 through the second claw 86203. At this time, the rotation speed of the driving body 7 is greater than the rotation speed of the sixth rotating body 86, so the connection between the sixth rotating body 86 and the shell 3 does not transmit motion. At this time, the rotation speed of the shell 3 is the same as the rotation speed of the driving body 7, which is a constant speed.

[0043] When the first rotating body 81 continues to move in the direction away from the second rotating body 82, the first rotating body 81 is not connected to the second rotating body 82, and the inclined surface 81205 on the control trigger member of the first rotating body contacts the inclined surface 7305 of the connecting component. As the first rotating body 81 continues to move, the convex surface 81204 on the control trigger member of the first rotating body contacts the second end 7304 of the connecting component. At this time, the first end 7303 of the connecting component is not in contact with the third slot 33 on the shell, and the driving body 7 is not connected to the shell 3. The first rotating body 81 decelerates and transmits the motion to the fifth rotating body 85 through the second transmission part 9. The fifth rotating body 85 transmits the motion to the sixth rotating body 86 through the first claw 85104. The sixth rotating body 86 is connected to the shell 3 through the second claw 86203. At this time, the motion is transmitted to the shell 3 through the sixth rotating body 86, and the rotation speed of the shell 3 is the same as the rotation speed of the sixth rotating body 86, which is deceleration.

[0044] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An internal fixed axis transmission for a bicycle, characterized in that: include: A first transmission part, comprising a first rotating body, a second rotating body and a first fixed shaft that is rotatable and used to support the first rotating body, the first rotating body can move axially on the first fixed shaft, and can achieve transmission connection with the second rotating body during the movement, and the second rotating body rotates coaxially with the first rotating body; The second transmission part includes a third rotating body drivingly connected to the first rotating body and a fourth rotating body drivingly connected to the second rotating body, the third rotating body can rotate around the second fixed axis, the first fixed axis and the second fixed axis are arranged in parallel and are relatively stationary; the second transmission part is also provided with a rotating body base, the rotating body base is located between the third rotating body and the fourth rotating body, the rotating body base is connected to the first fixed axis by a key, and a first elastic retaining ring is provided on the side of the rotating body base to limit the axial movement of the rotating body base along the first fixed axis; A driving body, which rotates around a first fixed axis and is used to transmit a human driving force to the first rotating body; The first transmission part also includes a fifth rotating body connected to the third rotating body and a sixth rotating body connected to the fourth rotating body, and the fifth rotating body and the sixth rotating body both rotate around the first fixed axis; a first overrunning clutch is arranged between the fifth rotating body and the sixth rotating body; a second overrunning clutch is arranged between the sixth rotating body and the housing; the fixed axis transmission also includes a housing and a connecting component installed on the driving body and used to connect the driving body and the housing; a convex surface for separating the driving body from the housing is arranged on the first rotating body, and when the first rotating body moves on the first fixed axis, if the convex surface on the first rotating body contacts the connecting component, the driving body is separated from the housing; a recessed portion or a convex portion matching the connecting component is arranged on the housing.

2. The internal fixed axis transmission for bicycle according to claim 1, characterized in that: The first rotating body and the second rotating body are connected in transmission by mutually matching the concave part and the convex part.

3. The internal fixed axis transmission for bicycle according to claim 2, characterized in that: The rotation axis of the fourth rotating body is parallel to or coincides with the central axis of the second fixed shaft.

4. The internal fixed-axis transmission for a bicycle according to claim 1, characterized in that: The first transmission part, the second transmission part, the driving body and the connecting component are all arranged in the shell.

5. The internal fixed axis transmission for bicycle according to claim 4, characterized in that: The first fixed shaft is also provided with a guide portion for guiding the first rotating body to move axially on the first fixed shaft.

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