阅读说明：本技术 四履带轮农用底盘 (Four-crawler-wheel agricultural chassis ) 是由 高志强 张敏 陈洪浪 何阳 张建文 李永刚 方明 朱锋文 廖胜利 吴宗群 夏振 于 2020-05-21 设计创作，主要内容包括：本发明公开了一种四履带轮农用底盘,包括底盘架,底盘架的两侧分别安装有两个履带行走轮,各履带行走轮独立的安装在底盘架上,底盘架上每一侧的两个履带行走轮连接一个独立的旋转驱动装置并由该旋转驱动装置驱动同步转动。该四履带轮农用底盘具有结构简单紧凑、成本低、安装及维护方便、转向性能好等优点。(The invention discloses a four-crawler-wheel agricultural chassis which comprises a chassis frame, wherein two crawler traveling wheels are respectively arranged on two sides of the chassis frame, each crawler traveling wheel is independently arranged on the chassis frame, and the two crawler traveling wheels on each side of the chassis frame are connected with an independent rotation driving device and driven by the rotation driving device to synchronously rotate. The four-crawler-wheel agricultural chassis has the advantages of simple and compact structure, low cost, convenience in installation and maintenance, good steering performance and the like.)

1. The utility model provides an agricultural chassis of four athey wheels, includes chassis underframe (1), two crawler-belt traveling wheels (2), its characterized in that are installed respectively to the both sides of chassis underframe (1): the crawler belt walking wheels (2) are independently arranged on the chassis frame (1), and the two crawler belt walking wheels (2) on each side of the chassis frame (1) are connected with an independent rotary driving piece (101) and driven by the rotary driving piece (101) to synchronously rotate.

2. The four-wheeled agricultural chassis of claim 1, wherein: the four-crawler-wheel agricultural chassis further comprises a steering control device (3) used for controlling and adjusting the rotating speed of each rotary driving piece (101), the steering control device (3) comprises a base (31) installed on the chassis frame (1), a steering wheel (32) rotatably installed on the base (31) and an electronic steering sensor (33) connected with a rotating shaft (321) of the steering wheel (32), the electronic steering sensor (33) is connected with a controller used for adjusting the rotating speed of the rotary driving pieces (101), an automatic return device used for driving the steering wheel (32) to automatically return is installed between the steering wheel (32) and the base (31), the automatic return device comprises a return rotating wheel (34) and a return matching surface (35) arranged on the base (31), the return matching surface (35) comprises a lowest point and two matching sections (351) extending to two sides from the lowest point around the rotating shaft (321), along extending direction cooperation section (351) of cooperation section (351) and base (31) interval on pivot (321) axial direction increase gradually, return runner (34) movable mounting be in pivot (321) go up and can rotate along with pivot (321) return fitting surface (35) motion, still install on pivot (321) and force return runner (34) with elastic component (36) of return fitting surface (35) laminating.

3. The four-wheeled agricultural chassis of claim 2, wherein: return runner (34) are installed on pivot (321) through swing mechanism with the swing mode, swing mechanism is including articulated swing arm (37) of installing on pivot (321), return runner (34) are installed on swing arm (37).

4. The four-wheeled agricultural chassis of claim 3, wherein: the rotating shaft (321) is provided with a groove, and the swing arm (37) is inserted into the groove and is hinged with the rotating shaft (321) through a hinge shaft.

5. The four-wheeled agricultural chassis of claim 4, wherein: elastic component (36) are flexible pressure spring, be equipped with on pivot (321) and block parts (38), flexible pressure spring cover is established on pivot (321), and the both ends of flexible pressure spring correspond respectively with block parts (38) and swing arm (37) offset to force swing arm (37) to make return runner (34) with the direction swing of return fitting surface (35) laminating.

6. The four-wheeled agricultural chassis of claim 2, wherein: and a groove for the return rotating wheel (34) to sink into to block the return rotating wheel (34) from rotating along with the rotating shaft (321) is arranged at the lowest point position on the return matching surface (35).

7. The four-wheeled agricultural chassis of claim 2, wherein: the extending ends of the two sections of matching sections (351) are connected to form an annular surface by the return matching surface (35), and a blocking piece (39) for blocking the return rotating wheel (34) is arranged at the connecting position of the extending ends of the two sections of matching sections (351).

8. The four-wheeled agricultural chassis of any one of claims 1 to 7, wherein: the driving end of each rotary driving piece (101) is connected with a gearbox (102), the output end of the gearbox (102) is connected with a crawler traveling wheel (2) through a transmission mechanism, the four-crawler-wheel agricultural chassis further comprises a synchronous gear shifting device (4) used for synchronously shifting two gearboxes (102), the synchronous gear shifting device (4) comprises a swing rod (42) and an articulated seat (41) installed on the chassis frame (1), the swing rod (42) is installed on the articulated seat (41) in a reciprocating swinging mode around a fixed axis, two ends of the swing rod (42) are respectively connected with a gear shifting sliding shaft (100) of one gearbox (102) through a connecting assembly, and the synchronous gear shifting device (4) further comprises a swing driving assembly used for driving the swing rod (42) to swing.

9. The four-wheeled agricultural chassis of claim 8, wherein: the connecting assembly comprises a connecting rod (43) connected with a swing rod (42), the connecting rod (43) is connected with the gear shifting sliding shaft (100), and the connecting rod (43) is installed on the swing rod (42) in a mode of elastic floating in the direction perpendicular to the swing axis of the swing rod (42) through an elastic floating mechanism.

10. The four-wheeled agricultural chassis of claim 9, wherein: elasticity floating machanism includes first expanding spring (44) and second expanding spring (45), be equipped with the through-hole on pendulum rod (42), connecting rod (43) wear to establish and install in the through-hole, be equipped with on connecting rod (43) and divide and locate first stop part (431) and second stop part (432) of through-hole both sides, first expanding spring (44) connect in between first stop part (431) and pendulum rod (42), second expanding spring (45) connect in between second stop part (432) and pendulum rod (42).

Technical Field

The invention relates to the technical field of walking chassis, in particular to a four-crawler-wheel agricultural chassis.

Background

In the existing crawler wheel type agricultural walking chassis, a front axle and a rear axle are arranged on a chassis frame, two ends of the front axle and the rear axle are respectively connected with and provided with a crawler wheel, and the speeds of the crawler wheels at the two ends of the front axle and the rear axle are inconsistent by utilizing a differential steering device during steering, so that the steering is realized. Because adopted front axle, rear axle and differential steering device, lead to having the structure complicacy, with high costs, installation and maintain inconvenient problem, simultaneously, the chassis underframe is with the rotational speed of two crawler travel wheels of one side through the differential steering device control front axle and rear axle simultaneously and control, and difficult assurance chassis underframe is with the same one side rotational speed unanimous of two crawler travel wheels.

Meanwhile, the conventional electronic steering wheel has no automatic return function, and after the steering wheel is rotated to steer, the steering wheel needs to be manually controlled to return and align, so that the defect of inconvenient operation exists, and the accuracy of the aligning angle is difficult to ensure when the steering wheel is manually controlled to return and align.

Disclosure of Invention

The invention aims to solve the technical problem of overcoming the defects in the prior art and provides the four-crawler-wheel agricultural chassis which is simple and compact in structure, low in cost, convenient to install and maintain and good in steering performance.

In order to solve the technical problems, the invention adopts the following technical scheme:

the four-crawler-wheel agricultural chassis comprises a chassis frame, wherein two crawler-wheel traveling wheels are respectively installed on two sides of the chassis frame, each crawler-wheel traveling wheel is independently installed on the chassis frame, and the two crawler-wheel traveling wheels on each side of the chassis frame are connected with an independent rotating driving piece and driven by the rotating driving piece to synchronously rotate.

As a further improvement of the above technical solution:

the four-crawler-wheel agricultural chassis further comprises a steering control device for controlling and adjusting the rotating speed of each rotary driving piece, the steering control device comprises a base arranged on the chassis frame, a steering wheel rotatably arranged on the base and an electronic steering sensor connected with a rotating shaft of the steering wheel, the electronic steering sensor is connected with a controller for adjusting the rotating speed of the rotary driving piece, an automatic return device for driving the steering wheel to automatically return is arranged between the steering wheel and the base, the automatic return device comprises a return rotating wheel and a return matching surface arranged on the base, the return matching surface comprises a lowest point and two matching sections extending to two sides respectively around a rotating shaft from the lowest point, the distance between the matching sections and the base in the axial direction of the rotating shaft is gradually increased along the extending direction of the matching sections, and the return rotating wheel is movably arranged on the rotating shaft and can move along the return matching surface along with the rotation of the rotating shaft, and the rotating shaft is also provided with an elastic component for forcing the return rotating wheel to be attached to the return matching surface.

The return runner is installed in the pivot through swing mechanism with the swing mode, swing mechanism is including articulated the swing arm of installing in the pivot, the return runner is installed on the swing arm.

The rotating shaft is provided with a groove, and the swing arm is inserted in the groove and is hinged with the rotating shaft through a hinge shaft.

The elastic component is a telescopic pressure spring, a blocking component is arranged on the rotating shaft, the telescopic pressure spring is sleeved on the rotating shaft, and two ends of the telescopic pressure spring respectively correspond to the blocking component and the swing arm to be abutted against each other so as to force the swing arm to swing towards the direction of enabling the return rotating wheel to be attached to the return fitting surface.

And a groove for the return rotating wheel to sink into so as to block the return rotating wheel from rotating along with the rotating shaft is arranged at the position of the lowest point on the return matching surface.

The extending ends of the two sections of matching sections are connected to form an annular surface, and a blocking piece for blocking the return rotating wheel is arranged at the position where the extending ends of the two sections of matching sections are connected.

The driving end of each rotary driving piece is connected with a gearbox, the output end of the gearbox is connected with a crawler traveling wheel through a transmission mechanism, the four-crawler agricultural chassis further comprises a synchronous gear shifting device used for synchronously shifting two gearboxes, the synchronous gear shifting device comprises a swing rod and an articulated seat installed on the chassis frame, the swing rod is installed on the articulated seat in a reciprocating swinging mode around a fixed axis, two ends of the swing rod are respectively connected with a gear shifting sliding shaft of one gearbox through a connecting assembly, and the synchronous gear shifting device further comprises a swing driving assembly used for driving the swing rod to swing.

The coupling assembling includes the connecting rod that links to each other with the pendulum rod, the connecting rod with the smooth hub connection of gear shift, the connecting rod passes through elastic floating mechanism and installs on the pendulum rod with the mode that can go up elastic floating in the direction of perpendicular to pendulum rod swing axis.

The elastic floating mechanism comprises a first telescopic spring and a second telescopic spring, a through hole is formed in the oscillating bar, the connecting rod is arranged in the through hole in a penetrating mode, a first limiting part and a second limiting part are arranged on the connecting rod and located on two sides of the through hole respectively, the first telescopic spring is connected between the first limiting part and the oscillating bar, and the second telescopic spring is connected between the second limiting part and the oscillating bar.

Compared with the prior art, the invention has the advantages that:

the four-crawler-wheel agricultural chassis has the advantages that the four-crawler-wheel agricultural chassis is simple and compact in structure, low in cost and convenient to install and maintain, the two crawler-wheel traveling wheels on the same side are driven by the same driving piece to rotate synchronously, the synchronism is good, and the steering performance of the four-crawler-wheel agricultural chassis can be improved.

Drawings

Fig. 1 is a front view structure schematic diagram of a four-crawler-wheel agricultural chassis.

Fig. 2 is a schematic bottom view of the four-track-wheel agricultural chassis.

Fig. 3 is an enlarged schematic view of a portion a in fig. 2.

Fig. 4 is a front view schematically showing the structure of the steering control device.

Fig. 5 is an enlarged schematic view of B in fig. 4.

Fig. 6 is a perspective view of the steering control device.

FIG. 7 is a first perspective view of a synchromesh transmission coupled to two gearboxes.

FIG. 8 is a perspective view of a second perspective of the synchromesh shift device coupled to two gearboxes.

FIG. 9 is a schematic perspective view of a synchro-shift device.

FIG. 10 is a schematic top view of the synchro-shift device.

Illustration of the drawings:

1. a chassis frame; 2. a crawler traveling wheel; 3. a steering control device; 31. a base; 32. a steering wheel; 321. a rotating shaft; 33. an electronic steering sensor; 34. returning the rotating wheel; 35. returning the matching surface; 351. a mating segment; 36. an elastic member; 37. swinging arms; 38. a blocking member; 39. a blocking member; 4. a synchro-shift device; 41. a hinged seat; 42. a swing rod; 43. a connecting rod; 431. a first limit member; 432. a second limiting component; 44. a first extension spring; 45. a second extension spring; 46. a rotating shaft; 47. a drive handle; 100. a shift slide shaft; 101. a rotary drive member; 102. a gearbox.

Detailed Description

The invention is described in further detail below with reference to the figures and specific examples.

As shown in fig. 1 and 2, the four-track-wheel agricultural chassis of the present embodiment includes a chassis frame 1, two track-walking wheels 2 are respectively mounted on two sides of the chassis frame 1, each track-walking wheel 2 is independently mounted on the chassis frame 1, and the two track-walking wheels 2 on each side of the chassis frame 1 are connected to an independent rotation driving member 101 and driven by the rotation driving member 101 to rotate synchronously. Each crawler traveling wheel 2 of this four-crawler-wheel agricultural chassis is independent installs on chassis underframe 1 to two crawler traveling wheels 2 of every side are rotated by an independent rotation driving piece 101 drive synchronization on chassis underframe 1, need not set up the front axle, rear axle and differential steering device, have simple structure compactness, with low costs, installation and maintenance convenient advantage, simultaneously with two crawler traveling wheels 2 of one side by same driving piece drive synchronization rotation, its synchronism is good, can improve four-crawler-wheel agricultural chassis's steering performance.

In this embodiment, the four-track wheel agricultural chassis further includes a steering control device 3 for controlling and adjusting the rotation speed of each rotary driving member 101, as shown in fig. 2 to 6, the steering control device 3 includes a base 31 mounted on the chassis frame 1, a steering wheel 32 rotatably mounted on the base 31, and an electronic steering sensor 33 connected to a rotating shaft 321 of the steering wheel 32, the electronic steering sensor 33 is connected to a controller for adjusting the rotation speed of the rotary driving member 101, an automatic returning device for automatically returning the steering wheel 32 is mounted between the steering wheel 32 and the base 31, the automatic returning device includes a returning rotating wheel 34 and a returning fitting surface 35 provided on the base 31, the returning fitting surface 35 includes a lowest point and two fitting sections 351 extending from the lowest point to both sides around the rotating shaft 321, and the distance between the fitting section 351 and the base 31 in the axial direction of the rotating shaft 321 gradually increases along the extending direction of the fitting sections 351, the return rotating wheel 34 is movably mounted on the rotating shaft 321 and can rotate along the return matching surface 35 along with the rotating shaft 321, and the rotating shaft 321 is further mounted with an elastic component 36 for forcing the return rotating wheel 34 to be attached to the return matching surface 35. When the self-return electronic steering wheel is used, in the process of rotating the steering wheel 32 to control steering, the return rotating wheel 34 rotates synchronously along with the rotating shaft 321 and keeps being attached to the return matching surface 35 under the elastic compression action of the elastic component 36, the controllability and the stability of steering operation are better due to the blocking action of the elastic component 36, after steering is completed and the steering wheel 32 is loosened, the return rotating wheel 34 can move to the lowest point along the return matching surface 35 under the elastic compression action of the elastic component 36, so that the rotating shaft 321 is driven to automatically return and return, and the steering wheel 32 is driven to automatically return. The electronic steering wheel realizes automatic return only through an automatic return device consisting of the return rotating wheel 34, the return matching surface 35 and the elastic part 36, does not need to be provided with a power part, and has the advantages of simple structure, low cost, easiness in manufacturing and assembling and good working stability.

In this embodiment, the rotary driving member 101 is a hydraulic motor, the electronic steering sensor 33 employs an encoding disk, the electronic steering sensor 33 detects a rotation angle of the rotating shaft 321, and sends a detection result to the processor, and the processor controls a rotation speed adjusting device of the hydraulic motor to operate according to the detection result to adjust a rotation speed of the hydraulic motor.

In this embodiment, the return wheel 34 is mounted on the rotating shaft 321 in a swinging manner through a swinging mechanism, the swinging mechanism includes a swinging arm 37 hinged on the rotating shaft 321, and the return wheel 34 is mounted on the swinging arm 37. The return runner 34 is installed on the rotating shaft 321 in a swinging manner through a swing arm 37 to realize the joint with the return matching surface 35 all the time, and the structure is simple and compact, the installation stability is good, and the manufacture, the assembly and the maintenance are easy.

In this embodiment, the rotating shaft 321 is provided with a groove, and the swing arm 37 is inserted into the groove and is hinged to the rotating shaft 321 through the hinge shaft, so that the installation stability can be further improved, and the space saving is facilitated.

In this embodiment, the elastic component 36 is a telescopic pressure spring, the rotating shaft 321 is provided with a blocking component 38, the telescopic pressure spring is sleeved on the rotating shaft 321, and two ends of the telescopic pressure spring respectively and correspondingly abut against the blocking component 38 and the swing arm 37, so as to force the swing arm 37 to swing in a direction in which the return rotating wheel 34 is attached to the return fitting surface 35. The telescopic compression spring has the advantages of simple structure, low cost and convenience in installation and maintenance, and is sleeved on the rotating shaft 321, so that the installation stability is good.

In this embodiment, it is preferable that the blocking component 38 is an annular sleeve which is sleeved on the outer portion of the rotating shaft 321, and the annular sleeve is in threaded fit connection with the rotating shaft 321 in a manner that the connection position can be adjusted along the axial direction of the rotating shaft 321. The axial connection position of the annular sleeve on the rotating shaft 321 is adjusted, and the compression degree of the telescopic pressure spring can be adjusted, so that the requirements of controllability and stability of steering operation and the requirement of automatic return are met.

In other embodiments, the elastic component 36 may also be a tension spring, and two ends of the tension spring are respectively connected to the rotating shaft 321 and the swing arm 37, so as to force the swing arm 37 to swing in a direction that the return roller 34 abuts against the return matching surface 35.

In this embodiment, the return engagement surface 35 is provided with a groove at the lowest point for the return roller 34 to sink into to block the return roller 34 from rotating along with the rotating shaft 321. When the return rotating wheel 34 returns to the initial position along the return matching surface 35, the return rotating wheel just sinks into the groove, and the return rotating wheel cannot continuously move along the return matching surface 35 due to inertia under the blocking effect of the groove, so that the return accuracy and stability are ensured.

In this embodiment, the extending ends of the two segments 351 are connected to form an annular surface, and the position where the extending ends of the two segments 351 are connected is provided with a blocking member 39 for blocking the return runner 34. The annular return engagement surface 35 is easier to manufacture, and the blocking member 39 limits the forward and reverse rotation angle of the steering wheel 32, so that the return runner 34 is prevented from moving from the engagement section 351 on one side to the engagement section 351 on the other side and being unable to return normally. Preferably, the base 31 has a cylindrical portion fitted around the outside of the rotating shaft 321, and the annular returning engagement surface 35 is provided at one end of the cylindrical portion.

In this embodiment, the high point and the lowest point are respectively disposed at two opposite sides of the axis of the rotating shaft 321, that is, the lengths of the two sections of the matching sections 351 are the same, so that the forward and reverse rotation angle ranges of the steering wheel 32 are also the same. Stop member 39 is removably attached to base 31 by fasteners to facilitate manufacturing assembly of return mating surface 35 and stop member 39 separately. The fastener may be a screw.

In this embodiment, as shown in fig. 7 to 10, a transmission case 102 is connected to a driving end of each rotary driving member 101, an output end of the transmission case 102 is connected to the crawler belt 2 through a transmission mechanism, the four-crawler agricultural chassis further includes a synchronous gear shifting device 4 for synchronously shifting two transmission cases 102, the synchronous gear shifting device 4 includes a swing link 42 and an articulated seat 41 installed on the chassis frame 1, the swing link 42 is installed on the articulated seat 41 in a manner of reciprocating swing around a fixed axis, two ends of the swing link 42 are respectively connected to a shift sliding shaft 100 of one transmission case 102 through a connecting assembly, and the synchronous gear shifting device 4 further includes a swing driving assembly for driving the swing link 42 to swing. The synchronous gear shifting device 4 adopts the swing driving component to drive the swing rod 42 to swing, utilizes the swing motion of the swing rod 42 to drive the gear shifting sliding shafts 100 of the two gearboxes 102 to synchronously slide so as to realize the synchronous gear shifting of the two gearboxes 102, has good gear shifting synchronism, only adopts the combination of the swing driving component and the swing rod 42, and has the advantages of simple and compact structure, low cost, simple and convenient control, and convenient manufacture, assembly and maintenance.

The transmission mechanism can adopt a gear transmission mechanism or a chain transmission mechanism or a belt transmission mechanism.

In this embodiment, the connecting assembly includes a connecting rod 43 connected to the swing link 42, and the connecting rod 43 is connected to the shift rail 100. The swing motion of the swing link 42 drives the shift sliding shaft 100 to slide back and forth through the connecting rod 43, and the structure is simple, the cost is low, and the assembly is easy.

In the present embodiment, the connecting rod 43 is mounted on the swing lever 42 via an elastic floating mechanism in such a manner as to be elastically floated in a direction perpendicular to the swing axis of the swing lever 42. Because the internal gear of the gearbox 102 can prevent the gear-shifting sliding shaft 100 from normally sliding to shift gears at a specific engagement position, namely at the moment of the specific engagement position, the gear-shifting sliding shaft 100 cannot normally slide to shift gears, the connecting rod 43 is installed on the swing rod 42 in an elastic floating manner, even if the swing rod 42 is controlled to swing at the moment, the elastic floating of the connecting rod 43 can automatically adapt to the situation, so that the situation that the gear-shifting sliding shaft 100 is forcibly driven to cause damage to the gearbox 102 or deformation of the swing rod 42 is avoided, and meanwhile, after the moment, the elastically floating connecting rod 43 can automatically return to the position, so that the gear-shifting sliding shaft 100 slides to be engaged with a. When the two gearboxes 102 are synchronously shifted, the internal gears of the two gearboxes 102 may have the phenomenon of asynchronous meshing, that is, at the moment of shifting, one gearbox 102 may be in a state of being capable of sliding the shifting sliding shaft 100 to shift gears, and the other gearbox 102 may be in a state of being incapable of sliding the shifting sliding shaft 100 to shift gears, and after the connecting rod 43 is installed in an elastic floating manner, the situation of being incapable of shifting gears can be avoided.

In this embodiment, the elastic floating mechanism includes a first expansion spring 44 and a second expansion spring 45, a through hole is provided on the swing rod 42, the connecting rod 43 is installed in the through hole in a penetrating manner, a first limiting part 431 and a second limiting part 432 are provided on the connecting rod 43 and are respectively provided at two sides of the through hole, the first expansion spring 44 is connected between the first limiting part 431 and the swing rod 42, and the second expansion spring 45 is connected between the second limiting part 432 and the swing rod 42. Under the condition that the connecting rod 43 is not stressed, the first telescopic spring 44 and the second telescopic spring 45 enable the connecting rod 43 to be kept relatively fixed, and when the connecting rod 43 is stressed, the connecting rod 43 can overcome the elastic acting force of the first telescopic spring 44 and the second telescopic spring 45 to move back and forth along the through hole, so that elastic floating installation of the connecting rod 43 is achieved. The elastic floating mechanism has the advantages of simple structure, low cost, stable and reliable work and easy manufacture and assembly.

In this embodiment, at least one of the first and second stoppers 431 and 432 is detachably connected to the connecting rod 43, so that the disassembly and assembly are facilitated.

In this embodiment, the first limiting part 431 is an annular boss structure integrally formed on the connecting rod 43, and the second limiting part 432 is a nut in threaded fit connection with the connecting rod 43. The structure is simple, the cost is low, and the manufacture and the assembly are easy.

In this embodiment, the connecting rod 43 is provided with a strip-shaped hole, and the shift sliding shaft 100 is connected with a connecting pin, which is inserted into the strip-shaped hole and can move along the strip-shaped hole. This can convert the swing motion of the swing link 42 into the sliding motion of the shift sliding shaft 100, and the connection structure and manner have the advantages of simple structure, low cost and easy manufacture.

In other embodiments, other connection structures between the connecting rod 43 and the shift sliding shaft 100 may be adopted as long as the swinging motion of the swing link 42 can be converted into the sliding motion of the shift sliding shaft 100, for example, an intermediate link is adopted, one end of the intermediate link is hinged with the connecting rod 43, and the other end of the intermediate link is hinged with the shift sliding shaft 100.

In this embodiment, the swing driving assembly includes a rotating shaft 46 rotatably mounted on the hinge base 41 and a driving handle 47 connected to the rotating shaft 46 for driving the rotating shaft 46 to rotate, the rotating shaft 46 is connected to the swing link 42, and the rotating axis of the rotating shaft 46 coincides with the swing axis of the swing link 42. The swing rod 42 can be driven to swing by driving the handle 47 to rotate the rotating shaft 46, so as to realize gear shifting. In other embodiments, the swing driving assembly can also adopt a motor to realize automatic driving gear shifting.

In this embodiment, the swing link 42 is fixedly connected to the rotating shaft 46 and reciprocally swings on the hinge base 41 through the rotating shaft 46, that is, the swing link 42 is used as both a swing mounting shaft of the swing link 42 and a driving shaft for driving the swing link 42 to swing, so that the structure is compact, the cost is reduced, and the manufacturing and assembling difficulty is reduced.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-described embodiments. Modifications and variations that may occur to those skilled in the art without departing from the spirit and scope of the invention are to be considered as within the scope of the invention.