CN111003101A

CN111003101A - A new type of transmission for bicycles

Info

Publication number: CN111003101A
Application number: CN201911426529.9A
Authority: CN
Inventors: 陈崇炯; 雷闽瑞; 陈煦煦
Original assignee: Wenzhou Polytechnic
Current assignee: Wenzhou Tongqing Vehicle Industry Co ltd
Priority date: 2019-12-26
Filing date: 2019-12-26
Publication date: 2020-04-14
Anticipated expiration: 2039-12-26
Also published as: CN111003101B

Abstract

The invention discloses a novel transmission device of a bicycle, comprising a reverse double crank mechanism and a speed-increasing direction changing mechanism. The reverse double crank mechanism includes an active crank, a connecting rod, a driven crank and a frame. The speed-increasing and direction-changing mechanism includes an internal gear, an idler gear and an external gear. One end of the active crank is fixedly connected to the central shaft, and the other end is provided with a screw hole to be threadedly connected to the first pin shaft. The outer circle of the first pin shaft is It is hinged with the connecting rod, the end is provided with an axial screw hole and is screwed with the pedal, the other end of the connecting rod is hinged with the end face of the internal gear, and the hinge point and the rotation center point of the internal gear form a driven crank, and the said connecting rod is hinged with the end face of the internal gear. The outer side of the idler gear meshes with the inner gear, and the inner side meshes with the outer gear. The inner gear drives the outer gear to rotate through the idler gear, and has more teeth than the outer gear. The inner hole of the outer gear is connected to the rear wheel hub through an overrunning clutch. By adopting the above structure, the rear wheel and the pedal board are in the same direction, no "dead point", and speed-up transmission is realized by changing the direction twice.

Description

Novel transmission device of bicycle

Technical Field

The invention relates to a bicycle, in particular to a novel transmission device of the bicycle.

Background

At present, most bicycle transmission devices adopt a chain wheel and chain transmission mechanism, the chain wheel and chain transmission mechanism is mature in technology, a driving chain wheel is installed on a middle shaft, a driven chain wheel is installed on a hub of a rear wheel, a front wheel steering wheel, a rear wheel driving wheel and a seat cushion are positioned in the middle, the bicycle transmission device is reasonable in structural arrangement, is suitable for occasions with severe environmental conditions, and has the characteristics of long service life, strong bearing capacity, large transmission, obvious acceleration and the like. Aiming at the phenomena of tooth jumping and chain dropping, related technicians design various bicycles without chains in sequence, which are roughly summarized as the following types: firstly, the chain wheel and chain transmission is changed into a wire harness or a synchronous belt, although the phenomena of tooth jumping and chain dropping do not exist, the wire harness and the synchronous belt are not suitable for occasions with severe environmental conditions, otherwise the service life of the wire harness and the synchronous belt is not long; secondly, the chain wheel and chain transmission is changed into conical gear transmission, and due to the limitation of space, the transmission is small, the speed increase is not obvious, and the labor is wasted; third, the driving pedal is directly mounted on the rear axle, the seat cushion is located above the rear wheel, the distance between the seat cushion and the handle becomes far away, the front wheel becomes small, the structural arrangement is unreasonable, and the advantages of the traditional bicycle cannot be exerted. Therefore, the technology of the existing chainless bicycle is not mature, and the problems are always existed.

Therefore, the inventor hopes to develop a chainless bicycle to overcome the above-mentioned defects of the prior chainless bicycle, and the transmission device is one of the key technologies.

Disclosure of Invention

Aiming at the defects and shortcomings of the prior art of the chainless bicycle, the invention provides a novel chainless bicycle, which can keep the advantages of the traditional bicycle and does not have the phenomena of tooth jumping and chain dropping in the chain wheel and chain transmission.

Aiming at the defects and shortcomings of the prior chainless bicycle technology, the invention provides a transmission mechanism which can realize continuous rotation and speed increase.

In order to achieve the above object, the present invention provides a novel transmission device for a bicycle, characterized in that: the reverse double-crank mechanism comprises a driving crank, a connecting rod, a driven crank and a rack, wherein a square hole is formed in the end A of the driving crank and fixedly connected with the square head of a center shaft, the speed-increasing and direction-changing mechanism comprises an inner gear, an idler wheel, an outer gear and a fixed support frame, the outer side of the idler wheel and the inner gear form an inner meshing gear pair, the inner side of the idler wheel and the outer gear form an outer meshing gear pair, the connecting rod is arranged on the outer sides of the driving crank and the inner gear, one end of the connecting rod is hinged to the end B of the driving crank through a first pin shaft, the other end of the connecting rod is hinged to the end face of the inner gear through a second pin shaft, a hinged point C of the inner gear and the connecting rod and the rotation central point D of the inner gear form the driven crank, the driving crank and the driven crank are equal in length, and, one end of the fixed support frame is provided with a round hole, the other end of the fixed support frame is provided with a boss, and an inner hole of the inner gear is hinged with the outer circle of the boss of the fixed support frame through a rolling bearing.

The invention has the beneficial effects that: by adopting the structure, the reverse double-crank mechanism ABCD can realize that the steering of the driven crank is opposite to that of the driving crank, has no 'dead point' and continuously rotates, and provides conditions for the next steering of the rear speed-increasing steering mechanism; the axes of the inner gear, the idler gear and the outer gear are all fixed, the number of teeth of the idler gear does not influence the size of the transmission ratio, but the steering of the outer gear is changed, the number of teeth of the inner gear is larger than that of the outer gear, the inner gear is driving, the outer gear is driven, and the transmission ratio is larger than 1, so that the speed-increasing transmission is realized, the riding is labor-saving, and the rear wheel and the pedal plate are steered to the same purpose.

The invention can be further provided with a square hole arranged in the axis direction of the boss of the fixed support frame, and the square hole is matched and fixedly connected with the square head of the rear shaft.

By adopting the further arrangement, the square hole is matched and fixedly connected with the square head, so that the assembly and disassembly are convenient and the connection is reliable.

The invention can be further arranged in that an overrunning clutch is arranged in the inner hole of the outer gear, the overrunning clutch comprises an inner ratchet wheel, a pawl, a connecting sleeve and a spring, the gear teeth of the inner ratchet wheel are uniformly distributed on the inner hole wall of the outer gear, the inner end of the pawl is hinged with the end surface of the connecting sleeve, the outer end of the pawl is abutted against the gear surface of the inner ratchet wheel, one end of the spring is fixedly connected with the end surface of the connecting sleeve, the other end of the spring is abutted against the side surface of the pawl, and the inner hole of the connecting sleeve is provided with internal threads which are in threaded connection with the external.

By adopting the further arrangement, the automatic connection and disconnection are achieved by utilizing the characteristics of the overrunning clutch, namely: when the rotating speed of the outer gear is greater than that of the hub of the rear wheel, the outer gear is automatically jointed, and the connecting sleeve is driven to rotate by the inner ratchet wheel and the pawl, so that the hub of the rear wheel rotates; when the rotation speed of the external gear is less than that of the rear wheel hub or the rotation directions of the external gear and the rear wheel hub are opposite, the external gear and the rear wheel hub are automatically separated, and the pawls slide over the tooth surfaces of the teeth of the internal ratchet wheel, so that the original rotation of the rear wheel hub is not influenced.

The invention can be further arranged in a way that the idler wheel is hinged with a middle shaft neck of a third pin shaft through a rolling bearing, one end of the third pin shaft penetrates through a round hole of the fixed support frame and is fixedly connected with the clamp spring, and the other end of the third pin shaft penetrates through an inner hole of the rolling bearing, a sleeve and a radial through hole at the lower end part of the rear upper right fork in sequence and is fixedly connected with a nut in a screwing way.

By adopting the further arrangement, the third pin shaft is fixed, the idler wheel can rotate around the third pin shaft, the sleeve and the nut axially position the idler wheel, the sliding friction of the rolling bearing is changed into rolling friction, the friction force is small, and the idler wheel can rotate more easily; the frame is connected with the third pin shaft, so that the strength, the rigidity and the stability of the whole vehicle are improved.

The invention can be further arranged in such a way that one end of the inner side of the first pin shaft is provided with an external thread which forms threaded connection with an internal thread hole of the driving crank, the axial direction of one end of the outer side is provided with an internal thread blind hole which forms threaded connection with the external thread of the pedal, and the middle part is provided with a shaft neck which is hinged with the connecting rod through a rolling bearing.

By adopting the further arrangement, the connecting rod and the pedal plate are arranged on the first pin shaft, the pedal plate rotates to drive the connecting rod to rotate, and the connecting rod cannot be blocked in the process of planar motion; the threaded connection is convenient to assemble and disassemble; the rolling bearing changes sliding friction into rolling friction, and the friction is small, so that the movement of the connecting rod is easier.

Drawings

FIG. 1 is a schematic view of the present invention applied to a chainless bicycle;

FIG. 2 is a schematic view of the present invention applied to a chainless bicycle transmission;

FIG. 3 is a block diagram of a reverse dual-crank mechanism of an embodiment of the present invention;

FIG. 4 is a structural diagram of a speed increasing and direction changing mechanism according to an embodiment of the present invention;

FIG. 5 is a block diagram of an overrunning clutch in accordance with an embodiment of the present invention;

FIG. 6 is a structural view of an internal gear of an embodiment of the present invention;

fig. 7 is a block diagram of an idler according to an embodiment of the present invention.

Detailed Description

As shown in fig. 2, 3, 4, 5, 6, and 7, the present invention provides a novel transmission device for a bicycle, comprising a reverse double crank mechanism 21 and a speed-increasing and direction-changing mechanism 22, wherein the reverse double crank mechanism 21 comprises a driving crank 211, a connecting rod 212, a driven crank 213, and a frame 214, the end a of the driving crank 211 is provided with a square hole to be fixedly connected with the square head of a central shaft 4, the speed-increasing and direction-changing mechanism 22 comprises an internal gear 221, an idle gear 222, an external gear 223, and a fixed support 224, the outer side of the idle gear 222 forms an internal gear pair with the internal gear 221, the inner side forms an external gear pair with the external gear 223, the connecting rod 212 is arranged outside the driving crank 211 and the internal gear 221, one end is hinged to the end B of the driving crank 211 through a first pin 215, the other end is hinged to the end face of the internal gear 221 through a second pin 216, and a hinge point C of the internal gear 221 and the connecting rod, the length of initiative crank 211 and driven crank 213 equal, the length of connecting rod 212 and frame 214 equals and nonparallel, has constituted reverse double crank mechanism ABCD21, fixed support frame 224 one end be equipped with the round hole, the other end is equipped with boss 2241, the hole of internal gear 221 pass through the boss 2241 excircle of antifriction bearing and fixed support frame 224 and articulate. By adopting the structure, the reverse double-crank mechanism ABCD21 can realize that the steering direction of the driven crank 213 is opposite to that of the driving crank 211, and the continuous rotation without a dead point is realized, and simultaneously, a condition is provided for the next steering direction change of the rear speed-increasing and direction-changing mechanism 22; the axes of the inner gear 221, the idler gear 222 and the outer gear 223 are all fixed, the number of teeth of the idler gear 222 does not affect the size of the transmission ratio, but the steering of the outer gear 223 is changed, the number of teeth of the inner gear 221 is larger than that of the teeth of the outer gear 223, the inner gear 221 is driving, the outer gear 223 is driven, and the transmission ratio is larger than 1, so that the purposes of speed-increasing transmission, labor saving in riding and the same steering of the wheel 3 and the pedal plate 217 are achieved. With the above further arrangement, the number of the idler pulleys 222 may be plural, and one is preferable in the present invention, which can reduce the cost and weight.

The invention can be further provided that a square hole is arranged in the axis direction of the boss 2241 of the fixed support frame 224, and the square hole is matched and fixedly connected with the square head of the rear shaft 5. By adopting the further arrangement, the square hole is matched and fixedly connected with the square head, so that the assembly and disassembly are convenient and the connection is reliable.

The invention can be further arranged in that an overrunning clutch 6 is arranged in the inner hole of the outer gear 223, the overrunning clutch 6 comprises an inner ratchet wheel 61, a pawl 62, a connecting sleeve 63 and a spring 64, the teeth of the inner ratchet wheel 61 are uniformly distributed on the inner hole wall of the outer gear 223, the inner end of the pawl 62 is hinged with the end surface of the connecting sleeve 63, the outer end of the pawl 62 is abutted against the tooth surface of the inner ratchet wheel 61, one end of the spring 64 is fixedly connected with the end surface of the connecting sleeve 63, the other end of the spring is abutted against the side surface of the pawl 62, and the inner hole of the connecting sleeve 63 is provided with an inner thread which is in threaded connection. By adopting the structure, the automatic connection and disconnection are achieved by utilizing the characteristics of the overrunning clutch 6, namely: when the rotating speed of the outer gear 223 is greater than that of the rear hub 321, the outer gear is automatically jointed, and the connecting sleeve 63 is driven to rotate through the inner ratchet wheel 61 and the pawl 62, so that the rear hub 321 rotates; when the rotation speed of the external gear 223 is less than the rotation speed of the rear hub 321 or the rotation directions of the external gear and the rear hub 321 are opposite, the external gear and the rear hub 321 are automatically separated, and the pawls 62 slide over the tooth surfaces of the internal ratchet 61, so that the original rotation of the rear hub 321 is not influenced. With the above further arrangement, the number of the pawls 62 and the springs 64 may be one, two or more, and two are preferable in the present invention, which is to balance the stress and improve the stability of the transmission on the one hand, and to make the structure as simple as possible on the other hand.

The invention can be further configured that the idler wheel 222 is hinged with the middle journal of the third pin shaft 225 through a rolling bearing, one end of the third pin shaft 225 passes through the circular hole of the fixed support frame 224 and is fixedly connected with the clamp spring 226, and the other end of the third pin shaft passes through the inner hole of the rolling bearing, the sleeve 228 and the radial through hole at the lower end part of the rear upper right fork 142 in sequence and is fixed with a nut in a threaded manner. By adopting the structure, the third pin shaft 225 is fixed, the idler pulley 222 can rotate around the third pin shaft 225, the sleeve 227 and the nut enable the idler pulley 222 to be axially positioned, the rolling bearing changes sliding friction into rolling friction, the friction force is small, and the idler pulley 222 can rotate more easily; the frame 1 is connected with the third pin shaft 225, so that the strength, the rigidity and the stability of the whole vehicle are improved.

The invention can be further arranged that one end of the inner side of the first pin shaft 215 is provided with an external thread which forms a threaded connection with an internal thread hole of the driving crank 211, the axial direction of one end of the outer side is provided with an internal thread blind hole which forms a threaded connection with an external thread of the pedal plate 217, and the middle part is provided with a shaft neck which is hinged with the connecting rod 212 through a rolling bearing. By adopting the structure, the connecting rod 212 and the pedal 217 are arranged on the first pin shaft 215, the pedal 217 rotates to drive the connecting rod 212 to rotate, and the connecting rod 212 cannot be blocked in the process of planar motion; the threaded connection is convenient to assemble and disassemble; the rolling bearing changes sliding friction into rolling friction, and the friction is small, so that the connecting rod 212 moves more easily.

As shown in fig. 1, the present invention is applied to a specific technical solution of a chainless bicycle, including a frame 1, a transmission device 2 and a wheel 3, wherein the frame 1 includes an upper tube 11, a lower tube 12, a vertical tube 13, a rear upper fork 14 and a rear lower fork 15, the transmission device 2 includes a reverse double crank mechanism 21 and a speed-increasing steering mechanism 22, the wheel 3 includes a front wheel 31 and a rear wheel 32, a circular hole is provided at a joint of the lower tube 12 and the vertical tube 13, the circular hole is hinged with an excircle of a bottom bracket 4, the rear upper fork 14 includes a left rear upper fork 141 and a right rear upper fork 142, the rear lower fork 15 includes a left rear lower fork 151 and a right rear lower fork 152, a connecting hole is provided at a joint of the left rear upper fork 141 and the left rear lower fork 151, the connecting hole is fixedly connected with one end of a rear axle 5, a radial through hole is provided at a middle lower portion of the right rear upper fork 142, and a radial through hole is provided at an end portion of the, and is fixedly connected through screws, and the transmission device 2 is arranged on the right outer side of the frame 1. By adopting the structure, the transmission device 2 is not only beneficial to installation, but also beneficial to flexible operation of the whole transmission system without being blocked.

Claims

1. A novel transmission device of a bicycle is characterized in that: the reverse double-crank mechanism comprises a driving crank, a connecting rod, a driven crank and a rack, wherein a square hole is formed in the end A of the driving crank and fixedly connected with the square head of a center shaft, the speed-increasing and direction-changing mechanism comprises an inner gear, an idler wheel, an outer gear and a fixed support frame, the outer side of the idler wheel and the inner gear form an inner meshing gear pair, the inner side of the idler wheel and the outer gear form an outer meshing gear pair, the connecting rod is arranged on the outer sides of the driving crank and the inner gear, one end of the connecting rod is hinged to the end B of the driving crank through a first pin shaft, the other end of the connecting rod is hinged to the end face of the inner gear through a second pin shaft, a hinge joint C and the rotation central point D of the inner gear form the driven crank, the driving crank and the driven crank are equal in length, the connecting rod and, one end of the fixed support frame is provided with a round hole, the other end of the fixed support frame is provided with a boss, and an inner hole of the inner gear is hinged with the outer circle of the boss of the fixed support frame through a rolling bearing.

2. The transmission of a bicycle according to claim 1, wherein: the boss axis direction of the fixed support frame is provided with a square hole, and the square hole is fixedly connected with the square head of the rear shaft in a matching manner.

3. The transmission of a bicycle according to claim 1, wherein: the outer gear hole in be equipped with freewheel clutch, freewheel clutch including interior ratchet, pawl, adapter sleeve and spring, the teeth of a cogwheel equipartition of interior ratchet on outer gear inner hole wall, the inner of pawl articulated with the terminal surface of adapter sleeve, outer end and interior ratchet wheel flank of tooth are inconsistent, spring one end and the terminal surface rigid coupling of adapter sleeve, the other end is inconsistent with the side of pawl, the adapter sleeve hole set up internal thread and rear wheel hub's external screw thread and constitute threaded connection.

4. The transmission of a bicycle according to claim 1, wherein: the idler wheel is hinged with a middle shaft neck of a third pin shaft through a rolling bearing, one end of the third pin shaft penetrates through a round hole of the fixed support frame and is fixedly connected with the clamp spring, and the other end of the third pin shaft penetrates through an inner hole of the rolling bearing, the sleeve and a radial through hole at the lower end part of the rear upper right fork in sequence and is fixedly connected with a nut in a threaded mode.

5. The transmission of a bicycle according to claim 1, wherein: the inner side end of the first pin shaft is provided with an external thread which forms threaded connection with an internal thread hole of the driving crank, an internal thread blind hole which forms threaded connection with an external thread of the pedal is arranged in the axis direction of the outer side end of the first pin shaft, and a shaft neck which is hinged with the connecting rod through a rolling bearing is arranged in the middle of the first pin shaft.