CN109131717B

CN109131717B - Low-cost sanitation tricycle speed change gear

Info

Publication number: CN109131717B
Application number: CN201810934193.6A
Authority: CN
Inventors: 不公告发明人
Original assignee: Permanently Happy Head Of District In Fuzhou City Wins Information Technology Co ltd
Current assignee: CHONGQING LIFAN THREE MOTORCYCLE Co.,Ltd.
Priority date: 2018-08-16
Filing date: 2018-08-16
Publication date: 2020-04-14
Anticipated expiration: 2038-08-16
Also published as: CN109131717A

Abstract

The invention belongs to the field of speed changing devices, and particularly relates to a low-cost sanitation tricycle speed changing device which comprises a first gear, a second gear, a rack, a second shaft sleeve, a sector plate, a second shaft hole, a first speed changing pin, a second speed changing pin, a third speed changing pin, a pulley, a fixed block, a steel wire rope, a driven wheel and the like, wherein the second shaft sleeve is arranged on a supporting shaft in a matched manner through a bearing of the inner circular surface of the second shaft sleeve and the outer circular surface of the supporting shaft; the first gear is nested on the outer circular surface of the second shaft sleeve through the inner circular surface of the first gear and is fixedly connected with the second shaft sleeve; the speed change device does not need excessive precision processing; the relative cost is low, and the reliability is high; the speed change device can realize the speed which is three times of the first gear at most, and the whole device occupies smaller space, thereby providing proper space for subsequent upgrading and reconstruction; in addition, the whole device is driven by a steel wire rope, so that the steel wire rope has relatively low cost, easy maintenance and convenient replacement; the invention has simple structure and better use effect.

Description

Low-cost sanitation tricycle speed change gear

Technical Field

The invention belongs to the field of speed changing devices, and particularly relates to a low-cost speed changing device for a sanitation tricycle.

Background

At present, the traditional sanitation tricycle is not provided with a speed change mechanism and is only driven by a certain speed ratio, and users of the sanitation tricycle can be different crowds, old and weak crowds or strong in age; if the tricycle has different speed ratios, different people can meet physical requirements of users when the tricycle is used by different people, and in order to save cost, the speed ratio of the tricycle can be determined after the users determine the speed ratio, and the transmission ratio change is not needed in the riding process. For a bicycle speed change mechanism, the speed of a two-wheel bicycle speed change device is changed by changing the matching of a chain and gear discs with different front and rear sizes; the size of the front fluted disc and the size of the rear fluted disc determine the force of the bicycle when the pedals are rotated; the bigger the front fluted disc is, the smaller the rear fluted disc is, and the harder the pedal feels; the smaller the front fluted disc is, and the larger the rear fluted disc is, the easier the pedals feel; in order to achieve the purpose of adjusting the optimal speed, a plurality of front gear discs and rear gears are combined in pairs, so that excessive space is occupied; the traditional speed change device has a complex structure and mainly depends on chain transmission; the chain structure is relatively complex, the production cost is high, and the difficulty of maintenance and replacement is relatively high; after a period of use, the speed change conversion device is likely to fail, and thus the ideal speed change effect is not achieved. The use of a transmission mechanism for a two-wheeled vehicle in a sanitation tricycle is obviously unsuitable. Therefore, the speed changing device suitable for the sanitation tricycle is needed to be designed.

The invention designs a low-cost sanitation tricycle speed changing device to solve the problems.

Disclosure of Invention

In order to solve the defects in the prior art, the invention discloses a low-cost sanitation tricycle speed changing device which is realized by adopting the following technical scheme.

The utility model provides a low-cost sanitation tricycle speed change gear which characterized in that: the device comprises a rear wheel shaft, a pedal shaft, a U-shaped crossbeam, a connecting rod, a supporting shaft, a second shaft sleeve, a sector plate, a second shaft hole, a first speed changing pin, a second speed changing pin, a third speed changing pin, five pulleys, a fixed block, a steel wire rope, a driven wheel, a first shaft hole, a movable circular groove, a one-way clutch, a volute spiral spring, a first shaft sleeve, a supporting block, a stop block, a reset spring, a first gear, a rack, a positioning block, a sliding groove, a second gear, a third shaft hole and teeth, wherein the second shaft sleeve is arranged on the supporting shaft through the matching of an inner circular surface of the second shaft sleeve and a bearing on the; the first gear is nested on the outer circular surface of the second shaft sleeve through the inner circular surface of the first gear and is fixedly connected with the second shaft sleeve; the radian of the sector plate is 90 degrees; a second shaft hole is formed in the end face of the sector plate, close to the arc center; the fan-shaped plate is nested on the outer circular surface of the second shaft sleeve through the second shaft hole and is fixedly connected with the second shaft sleeve; the first speed changing pin, the second speed changing pin and the third speed changing pin are arranged on the end surface of the sector plate; the distance between the center of the first speed change pin and the center of the second shaft hole is smaller than the distance between the center of the second speed change pin and the center of the second shaft hole; the distance between the center of the second shift pin and the center of the second shaft hole is smaller than the distance between the center of the third shift pin and the center of the second shaft hole; a certain included angle exists between a connecting line of the center of the first speed changing pin and the center of the second shaft hole and a connecting line of the center of the second speed changing pin and the center of the second shaft hole; a certain included angle exists between a connecting line of the center of the second speed changing pin and the center of the second shaft hole and a connecting line of the center of the third speed changing pin and the center of the second shaft hole;

the supporting block is arranged on the upper end surface of a U-shaped cross beam of the tricycle through one end of the supporting block; the five pulleys are respectively sequentially arranged on one side of the supporting block close to the sector plate from top to bottom through pins, and the intervals among the five pulleys are equal; a first pulley and a second pulley are matched with a first speed changing pin from bottom to top, a second pulley and a third pulley are matched with a second speed changing pin, and a third pulley and a fourth pulley are matched with a third speed changing pin; the fixed block is arranged on one side, close to the sector plate, of the supporting block and is positioned below the pulley at the lowest part; a third shaft hole is formed in the center of the end face of the second gear; the outer circular surface of the second gear is provided with teeth with a certain radian; the second gear is matched with a bearing of the pedal shaft through a third shaft hole and is arranged between the U-shaped cross beams of the tricycle; the upper end surface of the positioning block is provided with a sliding chute; the positioning block is arranged on the lower end face of the U-shaped cross beam through the upper end face of the positioning block; the rack is embedded into the chute in a sliding fit manner; one end of the rack is meshed with the first gear, and the other end of the rack is matched with the second gear;

the one-way clutch is arranged on the rear wheel shaft through the fixed connection between the inner circular surface of the one-way clutch and the outer circular surface of the rear wheel shaft; a movable circular groove is formed in the center of one end face of the driven wheel; a first shaft hole is formed in the center of the other end face of the driven wheel and communicated with the movable circular groove; the driven wheel is nested on the outer circular surface of the one-way clutch through the first shaft hole; the first shaft sleeve is arranged on the rear wheel shaft through the matching of the inner circular surface of the first shaft sleeve and a bearing on the outer circular surface of the rear wheel shaft, and one end of the first shaft sleeve is positioned in the movable circular groove of the driven wheel; one end of the first shaft sleeve extending out of the movable circular groove is fixedly connected with a U-shaped cross beam of the tricycle through a connecting rod; the volute spiral spring is wound on the outer circular surface of the first shaft sleeve and is positioned in the movable circular groove of the driven wheel; two ends of the volute spiral spring are respectively connected with the inner circular surface of the movable circular groove and the outer circular surface of the first shaft sleeve; one end of the steel wire rope is fixedly connected with the upper end face of the fixed block, and the other end of the steel wire rope rounds the uppermost pulley and is wound on the outer circular face of the driven wheel; the steel wire rope is matched with the five pulleys.

As a further improvement of the present technique, the first shift pin is in contact with the wire in an initial state.

As a further improvement of the present technology, the return spring is a compression spring.

As a further improvement of the technology, the radian of the circumferential extension of the tooth on the outer circular surface of the second gear is 30 degrees or 60 degrees or 90 degrees.

As a further improvement of the present technology, the pitch circle diameter of the first gear is equal to the pitch circle diameter of the second gear.

The design purpose that the reference circle diameter of the first gear is equal to that of the second gear is that the second gear rotates by the same angle as the first gear; when the teeth on the outer circular surface of the second gear are 30 degrees, the second gear drives the first gear to rotate by 30 degrees through the rack; when the teeth on the outer circular surface of the second gear are 60 degrees, the second gear drives the first gear to rotate for 60 degrees through the rack; when the teeth on the outer circular surface of the second gear are 90 degrees, the second gear drives the first gear to rotate 90 degrees through the rack.

The first speed changing pin, the second speed changing pin, the third speed changing pin, the pulley and the steel wire rope are designed in such a way that when the radian of teeth on the second gear is 30 degrees, a pedal is pedaled, and a pedal shaft is driven to rotate by the pedal; the pedal shaft drives the first speed changing pin, the second speed changing pin and the third speed changing pin to swing around the central line of the supporting shaft through the second gear, the rack, the first gear, the second shaft sleeve and the sector plate, and meanwhile, the return spring is compressed; the first speed changing pin presses the steel wire rope and penetrates through a space between the first pulley and the second pulley from bottom to top; the first speed changing pin presses and pulls the steel wire rope, so that the steel wire rope pulls the driven wheel to rotate; the driven wheel drives the rear wheel shaft to rotate through the one-way clutch; the driven wheel and the first shaft sleeve rotate relatively, so that the spiral spring deforms and stores energy; the rear wheel shaft drives the rear wheel of the tricycle to rotate, so that the tricycle moves forwards; in the process, the length of the steel wire rope is lengthened to be equal to twice of the swing amplitude of the first speed changing pin, namely the length of an arc line for pulling the driven wheel to rotate by the steel wire rope is twice of the swing amplitude of the first speed changing pin; when the pedal drives the second gear to rotate to 30 degrees, the rotating angle of the first gear is 30 degrees; the rotation is continued, the second gear and the rack are not meshed, and the second gear and the rack do not interact with each other; the pedal drives the second gear to continue rotating through the pedal shaft; under the action of the restoring force of the return spring, the rack drives the first speed changing pin, the second speed changing pin and the third speed changing pin to swing back through the first gear, the second shaft sleeve and the sector plate; the restoring force of the spiral spring makes the driven wheel rotate; the driven wheel drives the steel wire rope to rotate; the steel wire rope is wound on the outer circular surface of the driven wheel again; the steel wire rope is shortened and gradually tightened straight; when the second gear rotates 360 degrees and returns to the initial position, the return spring drives the first speed changing pin, the second speed changing pin and the third speed changing pin to return to the initial position through the rack, the first gear, the second shaft sleeve and the sector plate; the tricycle continues to move forwards under the action of inertia; the pedal is continuously trodden, the second gear continuously rotates from the initial position, the second gear continuously rotates under the action of the pedal, and the teeth of the second gear act with the rack in a reciprocating manner; the steel wire rope pulls the driven wheel in a circulating reciprocating manner, so that the rear wheel of the tricycle continuously rotates, and the tricycle continuously moves forwards; when the tricycle needs to move at a higher speed, the second gear needs to be replaced, the radian of teeth on the outer circular surface of the second gear is 60 degrees, and the pedals are pedaled and drive pedal shafts to rotate; the pedal shaft drives the first speed changing pin, the second speed changing pin and the third speed changing pin to swing around the central line of the supporting shaft through the second gear, the rack, the first gear, the second shaft sleeve and the sector plate; the first speed changing pin presses the steel wire rope and penetrates through a space between the first pulley and the second pulley from bottom to top; the first speed change pin presses and pulls the steel wire rope, so that the steel wire rope drives the rear wheel of the tricycle to rotate through the driven wheel, the one-way clutch and the rear wheel shaft; the tricycle is enabled to move forwards; meanwhile, the driven wheel and the first shaft sleeve rotate relatively, so that the volute spiral spring deforms and stores energy; before the second gear rotates to 30 degrees, the length of the steel wire rope is lengthened to be twice of the swing amplitude of the first speed changing pin, namely the length of an arc line for pulling the driven wheel to rotate by the steel wire rope is twice of the swing amplitude of the first speed changing pin; when the second gear drives the sector plate to swing to 30 degrees through the rack, the first gear and the second shaft sleeve, the second speed changing pin starts to contact with the steel wire rope and starts to press the steel wire rope; the second gear continues to rotate, and the second speed changing pin presses the steel wire rope and penetrates through a space between the second pulley and the third pulley from bottom to top; the first speed changing pin and the second speed changing pin press the steel wire rope together and enable the steel wire rope to pull the driven wheel to rotate; at the moment, the length of an arc line for pulling the driven wheel to rotate by the steel wire rope is four times of the swing amplitude of the sector plate, and the speed for driving the rear wheel to rotate by the driven wheel through the one-way clutch and the rear wheel shaft is twice of that before gear shifting; when the pedals drive the second gear to rotate by 60 degrees through the pedal shaft, the second gear drives the sector plate to swing by the rack, the first gear and the second shaft sleeve, and the swinging angle of the sector plate is 60 degrees; the pedal drives the second gear to continue rotating through the pedal shaft, the second gear is not meshed with the rack any more, and no action is generated between the second gear and the rack; the return spring drives the first speed changing pin, the second speed changing pin and the third speed changing pin to swing back through the rack, the first gear, the second shaft sleeve and the sector plate; the restoring force of the spiral spring makes the driven wheel rotate; the driven wheel drives the steel wire rope to rotate; the steel wire rope is wound on the outer circular surface of the driven wheel again; the steel wire rope is shortened and gradually tightened straight; when the second gear rotates to 360 degrees and returns to the initial position, the return spring drives the first speed changing pin, the second speed changing pin and the third speed changing pin to return to the initial position through the rack, the first gear, the second shaft sleeve and the sector plate; the tricycle continues to move forwards under the action of inertia; the pedals are continuously treaded, the second gear continuously rotates from the initial position, the first gear continuously rotates under the action of the pedals, the steel wire rope circularly and reciprocally pulls the driven wheel, so that the rear wheel of the tricycle continuously rotates, and the tricycle continuously moves forwards at the speed twice as fast as that before gear shifting; when the tricycle needs the fastest advancing speed, a second gear with 90-degree tooth radian needs to be replaced, and a pedal is pedaled and drives a pedal shaft to rotate; the pedal shaft drives the first speed changing pin, the second speed changing pin and the third speed changing pin to swing around the central line of the supporting shaft through the second gear, the rack, the first gear, the second shaft sleeve and the sector plate; the first speed changing pin presses the steel wire rope and penetrates through a space between the first pulley and the second pulley from bottom to top; the first speed change pin presses and pulls the steel wire rope, so that the steel wire rope drives the rear wheel of the tricycle to rotate through the driven wheel, the one-way clutch and the rear wheel shaft; the tricycle is enabled to move forwards; meanwhile, the driven wheel and the first shaft sleeve rotate relatively, so that the volute spiral spring deforms and stores energy; before the second gear rotates to 30 degrees, the length of the stretched steel wire rope is equal to twice of the swing amplitude of the first speed changing pin, namely the length of an arc line for pulling the driven wheel to rotate by the steel wire rope is twice of the swing amplitude of the first speed changing pin; when the second gear rotates to 30 degrees, the second speed changing pin starts to contact with the steel wire rope and starts to press the steel wire rope; the second gear continues to rotate, and the second speed changing pin presses the steel wire rope and penetrates through a space between the second pulley and the third pulley from bottom to top; the first speed changing pin and the second speed changing pin press the steel wire rope together and enable the steel wire rope to pull the driven wheel to rotate; at the moment, the length of an arc line for pulling the driven wheel to rotate by the steel wire rope is four times of the swing amplitude of the sector plate, and the speed for driving the rear wheel to rotate by the driven wheel through the one-way clutch and the rear wheel shaft is twice of that before gear shifting; when the second gear rotates to 60 degrees, the third speed changing pin starts to contact with the steel wire rope and starts to press the steel wire rope; the second gear continues to rotate, and the third speed changing pin presses the steel wire rope and penetrates through a space between the third pulley and the fourth pulley from bottom to top; when the pedals drive the second gear to rotate to 90 degrees through the pedal shaft, the second gear drives the sector plate to swing through the rack, the first gear and the second shaft sleeve, and the swinging range of the sector plate reaches the maximum, and the swinging angle of the sector plate is 90 degrees; the pedal drives the second gear to continue to rotate around the central line of the pedal shaft through the pedal shaft; the second gear and the rack are not meshed any more, and the second gear and the rack do not act; the return spring drives the first speed changing pin, the second speed changing pin and the third speed changing pin to swing back through the rack, the first gear, the second shaft sleeve and the sector plate; the restoring force of the spiral spring makes the driven wheel rotate; the driven wheel drives the steel wire rope to rotate; the steel wire rope is wound on the outer circular surface of the driven wheel again; the steel wire rope is shortened and gradually tightened straight; when the second gear rotates 360 degrees and returns to the initial position, the return spring drives the first speed changing pin, the second speed changing pin and the third speed changing pin to return to the initial position through the rack, the first gear, the second shaft sleeve and the sector plate; the tricycle continues to move forwards under the action of inertia; the pedals are continuously treaded, the second gear continuously rotates from the initial position, the second gear continuously rotates, the steel wire rope circularly and reciprocally pulls the driven wheel, the rear wheel of the tricycle continuously rotates, and the tricycle continuously moves forwards at the speed three times that of the first gear.

When the tricycle moves forward at a first gear, the radian of teeth on the second gear is 30 degrees, and the pedals are pedaled and drive pedal shafts to rotate; the pedal shaft drives the first speed changing pin, the second speed changing pin and the third speed changing pin to swing around the central line of the supporting shaft through the second gear, the rack, the first gear, the second shaft sleeve and the sector plate, and meanwhile, the return spring is compressed; the first speed changing pin presses the steel wire rope and penetrates through a space between the first pulley and the second pulley from bottom to top; the first speed changing pin presses and pulls the steel wire rope, so that the steel wire rope pulls the driven wheel to rotate; the driven wheel drives the rear wheel shaft to rotate through the one-way clutch; the driven wheel and the first shaft sleeve rotate relatively, so that the spiral spring deforms and stores energy; the rear wheel shaft drives the rear wheel of the tricycle to rotate, so that the tricycle moves forwards; in the process, the length of the steel wire rope is lengthened to be equal to twice of the swing amplitude of the first speed changing pin, namely the length of an arc line for pulling the driven wheel to rotate by the steel wire rope is twice of the swing amplitude of the first speed changing pin; when the pedal drives the second gear to rotate to 30 degrees, the rotating angle of the first gear is 30 degrees; the rotation is continued, the second gear and the rack are not meshed, and the second gear and the rack do not interact with each other; the pedal drives the second gear to continue rotating through the pedal shaft; under the action of the restoring force of the return spring, the rack drives the first speed changing pin, the second speed changing pin and the third speed changing pin to swing back through the first gear, the second shaft sleeve and the sector plate; the restoring force of the spiral spring makes the driven wheel rotate; the driven wheel drives the steel wire rope to rotate; the steel wire rope is wound on the outer circular surface of the driven wheel again; the steel wire rope is shortened and gradually tightened straight; when the second gear rotates 360 degrees and returns to the initial position, the return spring drives the first speed changing pin, the second speed changing pin and the third speed changing pin to return to the initial position through the rack, the first gear, the second shaft sleeve and the sector plate; the tricycle continues to move forwards under the action of inertia; the pedal is continuously trodden, the second gear continuously rotates from the initial position, the second gear continuously rotates under the action of the pedal, and the teeth of the second gear act with the rack in a reciprocating manner; the steel wire rope pulls the driven wheel in a reciprocating way, so that the rear wheel of the tricycle continuously rotates, and the tricycle continuously moves forwards.

When the tricycle needs to move at a higher speed, the second gear needs to be replaced, the radian of teeth on the outer circular surface of the second gear is 60 degrees, and the pedals are pedaled and drive pedal shafts to rotate; the pedal shaft drives the first speed changing pin, the second speed changing pin and the third speed changing pin to swing around the central line of the supporting shaft through the second gear, the rack, the first gear, the second shaft sleeve and the sector plate; the first speed changing pin presses the steel wire rope and penetrates through a space between the first pulley and the second pulley from bottom to top; the first speed change pin presses and pulls the steel wire rope, so that the steel wire rope drives the rear wheel of the tricycle to rotate through the driven wheel, the one-way clutch and the rear wheel shaft; the tricycle is enabled to move forwards; meanwhile, the driven wheel and the first shaft sleeve rotate relatively, so that the volute spiral spring deforms and stores energy; before the second gear rotates to 30 degrees, the length of the steel wire rope is lengthened to be twice of the swing amplitude of the first speed changing pin, namely the length of an arc line for pulling the driven wheel to rotate by the steel wire rope is twice of the swing amplitude of the first speed changing pin; when the second gear drives the sector plate to swing to 30 degrees through the rack, the first gear and the second shaft sleeve, the second speed changing pin starts to contact with the steel wire rope and starts to press the steel wire rope; the second gear continues to rotate, and the second speed changing pin presses the steel wire rope and penetrates through a space between the second pulley and the third pulley from bottom to top; the first speed changing pin and the second speed changing pin press the steel wire rope together and enable the steel wire rope to pull the driven wheel to rotate; at the moment, the length of an arc line for pulling the driven wheel to rotate by the steel wire rope is four times of the swing amplitude of the sector plate, and the speed for driving the rear wheel to rotate by the driven wheel through the one-way clutch and the rear wheel shaft is twice of that before gear shifting; when the pedals drive the second gear to rotate by 60 degrees through the pedal shaft, the second gear drives the sector plate to swing by the rack, the first gear and the second shaft sleeve, and the swinging angle of the sector plate is 60 degrees; the pedal drives the second gear to continue rotating through the pedal shaft, the second gear is not meshed with the rack any more, and no action is generated between the second gear and the rack; the return spring drives the first speed changing pin, the second speed changing pin and the third speed changing pin to swing back through the rack, the first gear, the second shaft sleeve and the sector plate; the restoring force of the spiral spring makes the driven wheel rotate; the driven wheel drives the steel wire rope to rotate; the steel wire rope is wound on the outer circular surface of the driven wheel again; the steel wire rope is shortened and gradually tightened straight; when the second gear rotates to 360 degrees and returns to the initial position, the return spring drives the first speed changing pin, the second speed changing pin and the third speed changing pin to return to the initial position through the rack, the first gear, the second shaft sleeve and the sector plate; the tricycle continues to move forwards under the action of inertia; the pedals are continuously treaded, the second gear continuously rotates from the initial position, the first gear continuously rotates under the action of the pedals, the steel wire rope circularly and reciprocally pulls the driven wheel, the rear wheel of the tricycle continuously rotates, and the tricycle continuously moves forwards at the speed twice as fast as that before gear shifting.

When the tricycle needs the fastest advancing speed, a second gear with 90-degree tooth radian needs to be replaced, and a pedal is pedaled and drives a pedal shaft to rotate; the pedal shaft drives the first speed changing pin, the second speed changing pin and the third speed changing pin to swing around the central line of the supporting shaft through the second gear, the rack, the first gear, the second shaft sleeve and the sector plate; the first speed changing pin presses the steel wire rope and penetrates through a space between the first pulley and the second pulley from bottom to top; the first speed change pin presses and pulls the steel wire rope, so that the steel wire rope drives the rear wheel of the tricycle to rotate through the driven wheel, the one-way clutch and the rear wheel shaft; the tricycle is enabled to move forwards; meanwhile, the driven wheel and the first shaft sleeve rotate relatively, so that the volute spiral spring deforms and stores energy; before the second gear rotates to 30 degrees, the length of the stretched steel wire rope is equal to twice of the swing amplitude of the first speed changing pin, namely the length of an arc line for pulling the driven wheel to rotate by the steel wire rope is twice of the swing amplitude of the first speed changing pin; when the second gear rotates to 30 degrees, the second speed changing pin starts to contact with the steel wire rope and starts to press the steel wire rope; the second gear continues to rotate, and the second speed changing pin presses the steel wire rope and penetrates through a space between the second pulley and the third pulley from bottom to top; the first speed changing pin and the second speed changing pin press the steel wire rope together and enable the steel wire rope to pull the driven wheel to rotate; at the moment, the length of an arc line for pulling the driven wheel to rotate by the steel wire rope is four times of the swing amplitude of the sector plate, and the speed for driving the rear wheel to rotate by the driven wheel through the one-way clutch and the rear wheel shaft is twice of that before gear shifting; when the second gear rotates to 60 degrees, the third speed changing pin starts to contact with the steel wire rope and starts to press the steel wire rope; the second gear continues to rotate, and the third speed changing pin presses the steel wire rope and penetrates through a space between the third pulley and the fourth pulley from bottom to top; when the pedals drive the second gear to rotate to 90 degrees through the pedal shaft, the second gear drives the sector plate to swing through the rack, the first gear and the second shaft sleeve, and the swinging range of the sector plate reaches the maximum, and the swinging angle of the sector plate is 90 degrees; the pedal drives the second gear to continue to rotate around the central line of the pedal shaft through the pedal shaft; the second gear and the rack are not meshed any more, and the second gear and the rack do not act; the return spring drives the first speed changing pin, the second speed changing pin and the third speed changing pin to swing back through the rack, the first gear, the second shaft sleeve and the sector plate; the restoring force of the spiral spring makes the driven wheel rotate; the driven wheel drives the steel wire rope to rotate; the steel wire rope is wound on the outer circular surface of the driven wheel again; the steel wire rope is shortened and gradually tightened straight; when the second gear rotates 360 degrees and returns to the initial position, the return spring drives the first speed changing pin, the second speed changing pin and the third speed changing pin to return to the initial position through the rack, the first gear, the second shaft sleeve and the sector plate; the tricycle continues to move forwards under the action of inertia; the pedals are continuously treaded, the second gear continuously rotates from the initial position, the second gear continuously rotates, the steel wire rope circularly and reciprocally pulls the driven wheel, the rear wheel of the tricycle continuously rotates, and the tricycle continuously moves forwards at the speed three times that of the first gear.

Compared with the traditional speed change device, the speed change device does not need excessive precision machining; the relative cost is low, and the reliability is high; the speed change device can realize the speed which is three times of the first gear at most, and the whole device occupies smaller space, thereby providing proper space for subsequent upgrading and reconstruction; in addition, the whole device is driven by a steel wire rope, so that the steel wire rope has relatively low cost, easy maintenance and convenient replacement; the invention has simple structure and better use effect.

Drawings

FIG. 1 is a schematic perspective view of a tricycle in its entirety.

Fig. 2 is a partial schematic view of the transmission engaged with a tricycle.

Fig. 3 is a cross-sectional view of the transmission engaged with a tricycle.

Fig. 4 is a schematic view of a transmission mounting position.

Fig. 5 is a sectional view showing a mounting position of the transmission.

Fig. 6 is a second gear schematic.

Fig. 7 is a schematic view of a locating block.

FIG. 8 is a sectional view of the sector plate, the support shaft, the second sleeve, the first gear and the rack.

FIG. 9 is a mating view of the sector plate, the first shift pin, the second shift pin and the third shift pin.

FIG. 10 is a schematic view of the support block, the fixed block and the pulley.

FIG. 11 is a cross-sectional view of the rear axle, the first sleeve, the volute spiral spring, the one-way clutch and the driven wheel.

Fig. 12 is a schematic view of the driven wheel.

Fig. 13 is a simplified schematic of the transmission.

Number designation in the figures: 1. a rear wheel axle; 2. a pedal shaft; 3. a U-shaped cross beam; 4. a connecting rod; 5. a support shaft; 6. a second shaft sleeve; 7. a sector plate; 8. a second shaft hole; 9. a first shift pin; 10. a pulley; 11. a fixed block; 12. a wire rope; 13. a driven wheel; 14. a first shaft hole; 15. a movable circular groove; 16. a one-way clutch; 17. a volute spiral spring; 18. a first bushing; 19. a support block; 20. a stopper; 21. a return spring; 22. a first gear; 23. a rack; 24. positioning blocks; 25. a chute; 26. a second gear; 27. a third shaft hole; 28. teeth; 29. a second shift pin; 30. and a third shift pin.

Detailed Description

As shown in fig. 1, 4 and 5, the rear axle comprises a rear axle 1, a pedal axle 2, a U-shaped cross beam 3, an engaging rod 4, a support axle 5, a second axle sleeve 6, a sector plate 7, a second axle hole 8, a first speed changing pin 9, a second speed changing pin 29, a third speed changing pin 30, five pulleys 10, a fixed block 11, a steel wire rope 12, a driven wheel 13, a first axle hole 14, a movable circular groove 15, a one-way clutch 16, a volute spring 17, a first axle sleeve 18, a supporting block 19, a stopper 20, a return spring 21, a first gear 22, a rack 23, a positioning block 24, a sliding groove 25, a second gear 26, a third axle hole 27 and teeth 28, wherein as shown in fig. 8, the second axle sleeve 6 is mounted on the support axle 5 through the inner circular surface thereof and the bearing of the outer circular surface of; the first gear 22 is nested on the outer circular surface of the second shaft sleeve 6 through the inner circular surface and is fixedly connected with the second shaft sleeve; as shown in fig. 9, the arc of the sector plate 7 is 90 degrees; a second shaft hole 8 is formed in the end face of the sector plate 7, close to the arc center; as shown in fig. 5 and 8, the sector plate 7 is nested on the outer circular surface of the second shaft sleeve 6 through the second shaft hole 8 and is fixedly connected with the outer circular surface; as shown in fig. 9, the first shift pin 9, the second shift pin 29, and the third shift pin 30 are mounted on the end face of the sector plate 7; the distance of the line connecting the center of the first gearshift pin 9 and the center of the second shaft hole 8 is smaller than the distance of the line connecting the center of the second gearshift pin 29 and the center of the second shaft hole 8; the distance of the connecting line of the center of the second gearshift pin 29 and the center of the second shaft hole 8 is smaller than the distance of the connecting line of the center of the third gearshift pin 30 and the center of the second shaft hole 8; an included angle is formed between a connecting line of the center of the first speed changing pin 9 and the center of the second shaft hole 8 and a connecting line of the center of the second speed changing pin 29 and the center of the second shaft hole 8; an included angle is formed between a connecting line of the center of the second shift pin 29 and the center of the second shaft hole 8 and a connecting line of the center of the third shift pin 30 and the center of the second shaft hole 8;

as shown in fig. 2 and 4, the supporting block 19 is mounted on the upper end surface of the U-shaped cross beam 3 of the tricycle through one end thereof; as shown in fig. 10, five pulleys 10 are respectively installed on one side of the supporting block 19 close to the sector plate 7 from top to bottom in sequence through pins, and the intervals between the five pulleys 10 are equal; as shown in fig. 3 and 5, the first pulley 10 and the second pulley 10 from bottom to top are engaged with the first shift pin 9, the second pulley 10 and the third pulley 10 are engaged with the second shift pin 29, and the third pulley 10 and the fourth pulley 10 are engaged with the third shift pin 30; as shown in fig. 10, the fixing block 11 is mounted on the supporting block 19 on a side close to the sector plate 7, and the fixing block 11 is located below the lowermost pulley 10; as shown in fig. 6, a third shaft hole 27 is formed in the center of the end surface of the second gear 26; the outer circle surface of the second gear 26 is provided with teeth 28 with a certain radian; as shown in fig. 4 and 5, the second gear 26 is installed between the U-shaped cross member 3 of the tricycle through the third shaft hole 27 and the bearing of the pedal shaft 2; as shown in fig. 7, the upper end surface of the positioning block 24 is provided with a sliding groove 25; as shown in fig. 2 and 8, the positioning block 24 is mounted on the lower end surface of the U-shaped cross beam 3 through the upper end surface thereof; as shown in fig. 3, the rack 23 is inserted into the slide groove 25 by a slide fit; one end of the rack 23 is meshed with the first gear 22, and the other end is matched with the second gear 26;

as shown in fig. 5, 11, the one-way clutch 16 is mounted on the rear wheel axle 1 through a fixed connection between its inner circular surface and the outer circular surface of the rear wheel axle 1; as shown in fig. 12, a movable circular groove 15 is formed in the center of one end face of the driven wheel 13; a first shaft hole 14 is formed in the center of the other end face of the driven wheel 13, and the first shaft hole 14 is communicated with the movable circular groove 15; as shown in fig. 5 and 11, the driven wheel 13 is nested on the outer circumferential surface of the one-way clutch 16 through the first shaft hole 14; as shown in fig. 4 and 11, the first sleeve 18 is mounted on the rear wheel axle 1 by its inner circular surface fitting with a bearing on the outer circular surface of the rear wheel axle 1, and one end of the first sleeve 18 is located in the movable circular groove 15 of the driven wheel 13; one end of the first shaft sleeve 18 extending out of the movable circular groove 15 is fixedly connected with a U-shaped cross beam 3 of the tricycle through a connecting rod 4; a volute spiral spring 17 is wound on the outer circular surface of the first shaft sleeve 18 and is positioned in the movable circular groove 15 of the driven wheel 13; two ends of the scroll spring 17 are respectively connected with the inner circular surface of the movable circular groove 15 and the outer circular surface of the first shaft sleeve 18; one end of a steel wire rope 12 is fixedly connected with the upper end face of the fixed block 11, and the other end of the steel wire rope rounds the uppermost pulley 10 and is wound on the outer circular face of the driven wheel 13; as shown in fig. 4 and 5, the wire rope 12 is engaged with five pulleys 10.

As shown in fig. 5 and 13, in the initial state, the first shift pin 9 is in contact with the wire.

As shown in fig. 5, the return spring 21 is a compression spring.

As shown in fig. 6, the arc of the teeth 28 extending circumferentially on the outer circumferential surface of the second gear 26 is 30 degrees, or 60 degrees, or 90 degrees.

As shown in fig. 3 and 4, the pitch circle diameter of the first gear 22 is equal to the pitch circle diameter of the second gear 26.

The design objective of the present invention that the reference circle diameter of the first gear 22 is equal to the reference circle diameter of the second gear 26 is that the second gear 26 rotates at an equal angle to the first gear 22; when the teeth 28 on the outer circumferential surface of the second gear 26 are 30 degrees, the second gear 26 drives the first gear 22 to rotate 30 degrees through the rack 23; when the teeth 28 on the outer circumferential surface of the second gear 26 are 60 degrees, the second gear 26 drives the first gear 22 to rotate 60 degrees through the rack 23; when the teeth 28 on the outer circumferential surface of the second gear 26 are at 90 degrees, the second gear 26 drives the first gear 22 to rotate by 90 degrees through the rack 23.

The first speed changing pin 9, the second speed changing pin 29, the third speed changing pin 30, the pulley 10 and the steel wire rope 12 are designed to pedal when the radian of the tooth 28 on the second gear 26 is 30 degrees, and the pedal drives the pedal shaft 2 to rotate; the pedal shaft 2 drives the first speed changing pin 9, the second speed changing pin 29 and the third speed changing pin 30 to swing around the central line of the supporting shaft 5 through the second gear 26, the rack 23, the first gear 22, the second shaft sleeve 6 and the sector plate 7, and meanwhile, the return spring 21 is compressed; the first speed changing pin 9 presses the steel wire rope 12 and penetrates between the first pulley 10 and the second pulley 10 from bottom to top; the first speed changing pin 9 presses and pulls the steel wire rope 12, so that the steel wire rope 12 pulls the driven wheel 13 to rotate; the driven wheel 13 drives the rear wheel shaft 1 to rotate through the one-way clutch 16; the driven wheel 13 and the first shaft sleeve 18 rotate relatively, so that the spiral spring 17 deforms and stores energy; the rear wheel shaft 1 drives the rear wheel of the tricycle to rotate, so that the tricycle moves forwards; in the process, the length of the steel wire rope 12 is lengthened to be equal to twice of the swinging amplitude of the first speed changing pin 9, namely the length of an arc line for pulling the driven wheel 13 to rotate by the steel wire rope 12 is twice of the swinging amplitude of the first speed changing pin 9; when the pedal drives the second gear 26 to rotate to 30 degrees, the first gear 22 rotates by 30 degrees; the rotation is continued, the second gear 26 is not meshed with the rack 23, and the second gear 26 does not interact with the rack 23; the pedal drives the second gear 26 to continue rotating through the pedal shaft 2; under the action of the restoring force of the return spring 21, the rack 23 drives the first speed change pin 9, the second speed change pin 29 and the third speed change pin 30 to swing back through the first gear 22, the second shaft sleeve 6 and the sector plate 7; the restoring force of the spiral spring 17 causes the driven pulley 13 to revolve; the driven wheel 13 drives the steel wire rope 12 to rotate; the steel wire rope 12 is wound on the outer circular surface of the driven wheel 13 again; the steel wire rope 12 is shortened and gradually tightened straight; when the second gear 26 rotates 360 degrees to return to the initial position, the return spring 21 drives the first shift pin 9, the second shift pin 29 and the third shift pin 30 to return to the initial position through the rack 23, the first gear 22, the second sleeve 6 and the sector plate 7; the tricycle continues to move forwards under the action of inertia; the pedal is continuously stepped, the second gear 26 continuously rotates from the initial position, the second gear 26 continuously rotates under the action of the pedal, and the teeth 28 of the second gear 26 circularly and reciprocally act with the rack 23; the steel wire rope 12 pulls the driven wheel 13 in a circulating reciprocating manner, so that the rear wheel of the tricycle continuously rotates, and the tricycle continuously moves forwards; when the tricycle needs to move at a higher speed, the second gear 26 needs to be replaced, the radian of teeth 28 on the outer circular surface of the second gear 26 is 60 degrees, and the pedals are pedaled and drive the pedal shaft 2 to rotate; the pedal shaft 2 drives the first speed changing pin 9, the second speed changing pin 29 and the third speed changing pin 30 to swing around the central line of the supporting shaft 5 through the second gear 26, the rack 23, the first gear 22, the second shaft sleeve 6 and the sector plate 7; the first speed changing pin 9 presses the steel wire rope 12 and penetrates between the first pulley 10 and the second pulley 10 from bottom to top; the first speed change pin 9 presses and pulls the steel wire rope 12, so that the steel wire rope 12 drives the rear wheel of the tricycle to rotate through the driven wheel 13, the one-way clutch 16 and the rear wheel shaft 1; the tricycle is enabled to move forwards; meanwhile, the driven wheel 13 and the first shaft sleeve 18 rotate relatively, so that the spiral spring 17 deforms and stores energy; before the second gear 26 rotates to 30 degrees, the length of the steel wire rope 12 is elongated to be equal to twice of the swing amplitude of the first shift pin 9, namely, the length of an arc of which the steel wire rope 12 pulls the driven wheel 13 to rotate is twice of the swing amplitude of the first shift pin 9; when the second gear 26 drives the sector plate 7 to swing to 30 through the rack 23, the first gear 22 and the second shaft sleeve 6, the second speed changing pin 29 starts to contact with the steel wire rope 12 and starts to press the steel wire rope 12; the second gear 26 continues to rotate, and the second speed changing pin 29 presses the steel wire rope 12 and penetrates between the second pulley 10 and the third pulley 10 from bottom to top; the first shift pin 9 and the second shift pin 29 together press the wire rope 12 and cause the wire rope 12 to pull the driven pulley 13 to rotate; at the moment, the length of an arc line for pulling the driven wheel 13 to rotate by the steel wire rope 12 is four times of the swing amplitude of the sector plate 7, and the speed of the driven wheel 13 for driving the rear wheel to rotate through the one-way clutch 16 and the rear wheel shaft 1 is twice of that before gear shifting; when the pedals drive the second gear 26 to rotate by 60 degrees through the pedal shaft 2, the second gear 26 drives the sector plate 7 to swing by the rack 23, the first gear 22 and the second shaft sleeve 6 to reach the maximum amplitude, and the swinging angle of the sector plate 7 is 60 degrees; the pedal drives the second gear 26 to continue rotating through the pedal shaft 2, the second gear 26 is not meshed with the rack 23 any more, and no action is generated between the second gear 26 and the rack 23; the return spring 21 drives the first speed changing pin 9, the second speed changing pin 29 and the third speed changing pin 30 to swing back through the rack 23, the first gear 22, the second shaft sleeve 6 and the sector plate 7; the restoring force of the spiral spring 17 causes the driven pulley 13 to revolve; the driven wheel 13 drives the steel wire rope 12 to rotate; the steel wire rope 12 is wound on the outer circular surface of the driven wheel 13 again; the steel wire rope 12 is shortened and gradually tightened straight; when the second gear 26 rotates to 360 degrees and returns to the initial position, the return spring 21 drives the first shift pin 9, the second shift pin 29 and the third shift pin 30 to return to the initial position through the rack 23, the first gear 22, the second sleeve 6 and the sector plate 7; the tricycle continues to move forwards under the action of inertia; the pedals are continuously stepped, the second gear 26 continuously rotates from the initial position, the first gear 22 continuously rotates under the action of the pedals, the steel wire rope 12 circularly and reciprocally pulls the driven wheel 13, so that the rear wheel of the tricycle continuously rotates, and the tricycle continuously moves forwards at the speed twice as fast as that before gear shifting; when the tricycle needs the fastest running speed, the second gear 26 with the tooth 28 and the radian of 90 degrees needs to be replaced, and the pedal is pedaled and drives the pedal shaft 2 to rotate; the pedal shaft 2 drives the first speed changing pin 9, the second speed changing pin 29 and the third speed changing pin 30 to swing around the central line of the supporting shaft 5 through the second gear 26, the rack 23, the first gear 22, the second shaft sleeve 6 and the sector plate 7; the first speed changing pin 9 presses the steel wire rope 12 and penetrates between the first pulley 10 and the second pulley 10 from bottom to top; the first speed change pin 9 presses and pulls the steel wire rope 12, so that the steel wire rope 12 drives the rear wheel of the tricycle to rotate through the driven wheel 13, the one-way clutch 16 and the rear wheel shaft 1; the tricycle is enabled to move forwards; meanwhile, the driven wheel 13 and the first shaft sleeve 18 rotate relatively, so that the spiral spring 17 deforms and stores energy; before the second gear 26 rotates to 30 degrees, the length of the steel wire rope 12 is elongated to be equal to twice of the swinging amplitude of the first shift pin 9, namely, the length of an arc of the steel wire rope 12 pulling the driven wheel 13 to rotate is twice of the swinging amplitude of the first shift pin 9; when the second gear 26 rotates to 30, the second shift pin 29 starts to contact the wire rope 12 and starts to press the wire rope 12; the second gear 26 continues to rotate, and the second speed changing pin 29 presses the steel wire rope 12 and penetrates between the second pulley 10 and the third pulley 10 from bottom to top; the first shift pin 9 and the second shift pin 29 together press the wire rope 12 and cause the wire rope 12 to pull the driven pulley 13 to rotate; at the moment, the length of an arc line for pulling the driven wheel 13 to rotate by the steel wire rope 12 is four times of the swing amplitude of the sector plate 7, and the speed of the driven wheel 13 for driving the rear wheel to rotate through the one-way clutch 16 and the rear wheel shaft 1 is twice of that before gear shifting; when the second gear 26 rotates to 60 degrees, the third shift pin 30 starts to contact the wire rope 12 and starts to press the wire rope 12; the second gear 26 continues to rotate, and the third speed changing pin 30 presses the steel wire rope 12 and penetrates through a space between the third pulley 10 and the fourth pulley 10 from bottom to top; when the pedals drive the second gear 26 to rotate to 90 degrees through the pedal shaft 2, the second gear 26 drives the sector plate 7 to swing to the maximum extent through the rack 23, the first gear 22 and the second shaft sleeve 6, and the swinging angle of the sector plate 7 is 90 degrees; the pedal drives the second gear 26 to continue rotating around the central line of the pedal shaft 2 through the pedal shaft 2; the second gear 26 is not meshed with the rack 23 any more, and the second gear 26 does not act on the rack 23; the return spring 21 drives the first speed changing pin 9, the second speed changing pin 29 and the third speed changing pin 30 to swing back through the rack 23, the first gear 22, the second shaft sleeve 6 and the sector plate 7; the restoring force of the spiral spring 17 causes the driven pulley 13 to revolve; the driven wheel 13 drives the steel wire rope 12 to rotate; the steel wire rope 12 is wound on the outer circular surface of the driven wheel 13 again; the steel wire rope 12 is shortened and gradually tightened straight; when the second gear 26 rotates 360 degrees to return to the initial position, the return spring 21 drives the first shift pin 9, the second shift pin 29 and the third shift pin 30 to return to the initial position through the rack 23, the first gear 22, the second sleeve 6 and the sector plate 7; the tricycle continues to move forwards under the action of inertia; the pedals are continuously stepped on, the second gear 26 continuously rotates from the initial position, the second gear 26 continuously rotates, the steel wire rope 12 circularly and reciprocally pulls the driven wheel 13, the rear wheel of the tricycle continuously rotates, and the tricycle continuously moves forwards at the speed three times that of the first gear.

The specific implementation mode is as follows: when the tricycle moves forward in a first gear, the radian of teeth 28 on the second gear 26 is 30 degrees, and the pedals are pedaled and drive the pedal shaft 2 to rotate; the pedal shaft 2 drives the first speed changing pin 9, the second speed changing pin 29 and the third speed changing pin 30 to swing around the central line of the supporting shaft 5 through the second gear 26, the rack 23, the first gear 22, the second shaft sleeve 6 and the sector plate 7, and meanwhile, the return spring 21 is compressed; the first speed changing pin 9 presses the steel wire rope 12 and penetrates between the first pulley 10 and the second pulley 10 from bottom to top; the first speed changing pin 9 presses and pulls the steel wire rope 12, so that the steel wire rope 12 pulls the driven wheel 13 to rotate; the driven wheel 13 drives the rear wheel shaft 1 to rotate through the one-way clutch 16; the driven wheel 13 and the first shaft sleeve 18 rotate relatively, so that the spiral spring 17 deforms and stores energy; the rear wheel shaft 1 drives the rear wheel of the tricycle to rotate, so that the tricycle moves forwards; in the process, the length of the steel wire rope 12 is lengthened to be equal to twice of the swinging amplitude of the first speed changing pin 9, namely the length of an arc line for pulling the driven wheel 13 to rotate by the steel wire rope 12 is twice of the swinging amplitude of the first speed changing pin 9; when the pedal drives the second gear 26 to rotate to 30 degrees, the first gear 22 rotates by 30 degrees; the rotation is continued, the second gear 26 is not meshed with the rack 23, and the second gear 26 does not interact with the rack 23; the pedal drives the second gear 26 to continue rotating through the pedal shaft 2; under the action of the restoring force of the return spring 21, the rack 23 drives the first speed change pin 9, the second speed change pin 29 and the third speed change pin 30 to swing back through the first gear 22, the second shaft sleeve 6 and the sector plate 7; the restoring force of the spiral spring 17 causes the driven pulley 13 to revolve; the driven wheel 13 drives the steel wire rope 12 to rotate; the steel wire rope 12 is wound on the outer circular surface of the driven wheel 13 again; the steel wire rope 12 is shortened and gradually tightened straight; when the second gear 26 rotates 360 degrees to return to the initial position, the return spring 21 drives the first shift pin 9, the second shift pin 29 and the third shift pin 30 to return to the initial position through the rack 23, the first gear 22, the second sleeve 6 and the sector plate 7; the tricycle continues to move forwards under the action of inertia; the pedal is continuously stepped, the second gear 26 continuously rotates from the initial position, the second gear 26 continuously rotates under the action of the pedal, and the teeth 28 of the second gear 26 circularly and reciprocally act with the rack 23; the steel wire rope 12 pulls the driven wheel 13 in a circulating reciprocating manner, so that the rear wheel of the tricycle continuously rotates, and the tricycle continuously moves forwards.

When the tricycle needs to move at a higher speed, the second gear 26 needs to be replaced, the radian of teeth 28 on the outer circular surface of the second gear 26 is 60 degrees, and the pedals are pedaled and drive the pedal shaft 2 to rotate; the pedal shaft 2 drives the first speed changing pin 9, the second speed changing pin 29 and the third speed changing pin 30 to swing around the central line of the supporting shaft 5 through the second gear 26, the rack 23, the first gear 22, the second shaft sleeve 6 and the sector plate 7; the first speed changing pin 9 presses the steel wire rope 12 and penetrates between the first pulley 10 and the second pulley 10 from bottom to top; the first speed change pin 9 presses and pulls the steel wire rope 12, so that the steel wire rope 12 drives the rear wheel of the tricycle to rotate through the driven wheel 13, the one-way clutch 16 and the rear wheel shaft 1; the tricycle is enabled to move forwards; meanwhile, the driven wheel 13 and the first shaft sleeve 18 rotate relatively, so that the spiral spring 17 deforms and stores energy; before the second gear 26 rotates to 30 degrees, the length of the steel wire rope 12 is elongated to be equal to twice of the swing amplitude of the first shift pin 9, namely, the length of an arc of which the steel wire rope 12 pulls the driven wheel 13 to rotate is twice of the swing amplitude of the first shift pin 9; when the second gear 26 drives the sector plate 7 to swing to 30 through the rack 23, the first gear 22 and the second shaft sleeve 6, the second speed changing pin 29 starts to contact with the steel wire rope 12 and starts to press the steel wire rope 12; the second gear 26 continues to rotate, and the second speed changing pin 29 presses the steel wire rope 12 and penetrates between the second pulley 10 and the third pulley 10 from bottom to top; the first shift pin 9 and the second shift pin 29 together press the wire rope 12 and cause the wire rope 12 to pull the driven pulley 13 to rotate; at the moment, the length of an arc line for pulling the driven wheel 13 to rotate by the steel wire rope 12 is four times of the swing amplitude of the sector plate 7, and the speed of the driven wheel 13 for driving the rear wheel to rotate through the one-way clutch 16 and the rear wheel shaft 1 is twice of that before gear shifting; when the pedals drive the second gear 26 to rotate by 60 degrees through the pedal shaft 2, the second gear 26 drives the sector plate 7 to swing by the rack 23, the first gear 22 and the second shaft sleeve 6 to reach the maximum amplitude, and the swinging angle of the sector plate 7 is 60 degrees; the pedal drives the second gear 26 to continue rotating through the pedal shaft 2, the second gear 26 is not meshed with the rack 23 any more, and no action is generated between the second gear 26 and the rack 23; the return spring 21 drives the first speed changing pin 9, the second speed changing pin 29 and the third speed changing pin 30 to swing back through the rack 23, the first gear 22, the second shaft sleeve 6 and the sector plate 7; the restoring force of the spiral spring 17 causes the driven pulley 13 to revolve; the driven wheel 13 drives the steel wire rope 12 to rotate; the steel wire rope 12 is wound on the outer circular surface of the driven wheel 13 again; the steel wire rope 12 is shortened and gradually tightened straight; when the second gear 26 rotates to 360 degrees and returns to the initial position, the return spring 21 drives the first shift pin 9, the second shift pin 29 and the third shift pin 30 to return to the initial position through the rack 23, the first gear 22, the second sleeve 6 and the sector plate 7; the tricycle continues to move forwards under the action of inertia; the pedals are continuously stepped on, the second gear 26 continues to rotate from the initial position, the first gear 22 continues to rotate under the action of the pedals, the steel wire rope 12 circularly and reciprocally pulls the driven wheel 13, so that the rear wheel of the tricycle continuously rotates, and the tricycle continuously moves forwards at the speed twice as fast as that before gear shifting.

When the tricycle needs the fastest running speed, the second gear 26 with the tooth 28 and the radian of 90 degrees needs to be replaced, and the pedal is pedaled and drives the pedal shaft 2 to rotate; the pedal shaft 2 drives the first speed changing pin 9, the second speed changing pin 29 and the third speed changing pin 30 to swing around the central line of the supporting shaft 5 through the second gear 26, the rack 23, the first gear 22, the second shaft sleeve 6 and the sector plate 7; the first speed changing pin 9 presses the steel wire rope 12 and penetrates between the first pulley 10 and the second pulley 10 from bottom to top; the first speed change pin 9 presses and pulls the steel wire rope 12, so that the steel wire rope 12 drives the rear wheel of the tricycle to rotate through the driven wheel 13, the one-way clutch 16 and the rear wheel shaft 1; the tricycle is enabled to move forwards; meanwhile, the driven wheel 13 and the first shaft sleeve 18 rotate relatively, so that the spiral spring 17 deforms and stores energy; before the second gear 26 rotates to 30 degrees, the length of the steel wire rope 12 is elongated to be equal to twice of the swinging amplitude of the first shift pin 9, namely, the length of an arc of the steel wire rope 12 pulling the driven wheel 13 to rotate is twice of the swinging amplitude of the first shift pin 9; when the second gear 26 rotates to 30, the second shift pin 29 starts to contact the wire rope 12 and starts to press the wire rope 12; the second gear 26 continues to rotate, and the second speed changing pin 29 presses the steel wire rope 12 and penetrates between the second pulley 10 and the third pulley 10 from bottom to top; the first shift pin 9 and the second shift pin 29 together press the wire rope 12 and cause the wire rope 12 to pull the driven pulley 13 to rotate; at the moment, the length of an arc line for pulling the driven wheel 13 to rotate by the steel wire rope 12 is four times of the swing amplitude of the sector plate 7, and the speed of the driven wheel 13 for driving the rear wheel to rotate through the one-way clutch 16 and the rear wheel shaft 1 is twice of that before gear shifting; when the second gear 26 rotates to 60 degrees, the third shift pin 30 starts to contact the wire rope 12 and starts to press the wire rope 12; the second gear 26 continues to rotate, and the third speed changing pin 30 presses the steel wire rope 12 and penetrates through a space between the third pulley 10 and the fourth pulley 10 from bottom to top; when the pedals drive the second gear 26 to rotate to 90 degrees through the pedal shaft 2, the second gear 26 drives the sector plate 7 to swing to the maximum extent through the rack 23, the first gear 22 and the second shaft sleeve 6, and the swinging angle of the sector plate 7 is 90 degrees; the pedal drives the second gear 26 to continue rotating around the central line of the pedal shaft 2 through the pedal shaft 2; the second gear 26 is not meshed with the rack 23 any more, and the second gear 26 does not act on the rack 23; the return spring 21 drives the first speed changing pin 9, the second speed changing pin 29 and the third speed changing pin 30 to swing back through the rack 23, the first gear 22, the second shaft sleeve 6 and the sector plate 7; the restoring force of the spiral spring 17 causes the driven pulley 13 to revolve; the driven wheel 13 drives the steel wire rope 12 to rotate; the steel wire rope 12 is wound on the outer circular surface of the driven wheel 13 again; the steel wire rope 12 is shortened and gradually tightened straight; when the second gear 26 rotates 360 degrees to return to the initial position, the return spring 21 drives the first shift pin 9, the second shift pin 29 and the third shift pin 30 to return to the initial position through the rack 23, the first gear 22, the second sleeve 6 and the sector plate 7; the tricycle continues to move forwards under the action of inertia; the pedals are continuously stepped on, the second gear 26 continuously rotates from the initial position, the second gear 26 continuously rotates, the steel wire rope 12 circularly and reciprocally pulls the driven wheel 13, the rear wheel of the tricycle continuously rotates, and the tricycle continuously moves forwards at the speed three times that of the first gear.

In the actual use process of the speed change mechanism, the sanitation tricycle is generally purchased by the government, and users of the tricycle may be old and weak, so that the sanitation tricycle is divided into three gears in design, and the government can adapt to different crowds by using different gears conveniently before purchasing and releasing. And the tricycle except the gear all belongs to necessary transmission structure other structures, has all fully used in three gears, does not have the structure of special gear, has saved the material and has improved the change efficiency.

In conclusion, the invention has the beneficial effects that: the speed change device does not need excessive precision processing; the chain wheel transmission device is relatively low in cost and high in reliability, and in addition, each chain wheel in the traditional variable speed chain is used in a specific gear for transmission, so that the chain wheel waste is caused; the speed change device can realize the speed which is three times of the first gear at most, and the whole device occupies smaller space, thereby providing proper space for subsequent upgrading and reconstruction; in addition, the whole device is driven by the steel wire rope 12, the steel wire rope 12 is low in relative cost, easy to maintain and convenient to replace.

Claims

1. The utility model provides a low-cost sanitation tricycle speed change gear which characterized in that: the device comprises a rear wheel shaft, a pedal shaft, a U-shaped crossbeam, a connecting rod, a supporting shaft, a second shaft sleeve, a sector plate, a second shaft hole, a first speed changing pin, a second speed changing pin, a third speed changing pin, five pulleys, a fixed block, a steel wire rope, a driven wheel, a first shaft hole, a movable circular groove, a one-way clutch, a volute spiral spring, a first shaft sleeve, a supporting block, a stop block, a reset spring, a first gear, a rack, a positioning block, a sliding groove, a second gear, a third shaft hole and teeth, wherein the second shaft sleeve is arranged on the supporting shaft through the matching of an inner circular surface of the second shaft sleeve and a bearing on the; the first gear is nested on the outer circular surface of the second shaft sleeve through the inner circular surface of the first gear and is fixedly connected with the second shaft sleeve; the radian of the sector plate is 90 degrees; a second shaft hole is formed in the end face of the sector plate, close to the arc center; the fan-shaped plate is nested on the outer circular surface of the second shaft sleeve through the second shaft hole and is fixedly connected with the second shaft sleeve; the first speed changing pin, the second speed changing pin and the third speed changing pin are arranged on the end surface of the sector plate; the distance between the center of the first speed change pin and the center of the second shaft hole is smaller than the distance between the center of the second speed change pin and the center of the second shaft hole; the distance between the center of the second shift pin and the center of the second shaft hole is smaller than the distance between the center of the third shift pin and the center of the second shaft hole; a certain included angle exists between a connecting line of the center of the first speed changing pin and the center of the second shaft hole and a connecting line of the center of the second speed changing pin and the center of the second shaft hole; a certain included angle exists between a connecting line of the center of the second speed changing pin and the center of the second shaft hole and a connecting line of the center of the third speed changing pin and the center of the second shaft hole;

2. The low cost sanitation tricycle speed change device of claim 1, wherein: in the initial state, the first speed changing pin is in contact with the steel wire rope.

3. The low cost sanitation tricycle speed change device of claim 1, wherein: the return spring is a compression spring.

4. The low cost sanitation tricycle speed change device of claim 1, wherein: the radian of the teeth extending on the circumferential direction of the outer circular surface of the second gear is 30 degrees, 60 degrees or 90 degrees.

5. The low cost sanitation tricycle speed change device of claim 1, wherein: the pitch circle diameter of the first gear is equal to the pitch circle diameter of the second gear.