CVT high-gear and low-gear integral gear transmission structure

Abstract

The utility model discloses a CVT (continuously variable transmission) high-low gear integral gear transmission structure, which belongs to the technical field of tractors and comprises a coupling power input shaft and a transmission shaft which are parallel to each other. One end of the coupling power input shaft is rotationally connected with one end of the power output shaft, and the end is connected with the power output shaft through the synchronizer assembly; the transmission shaft is in meshed connection with the coupling power input shaft and the power output shaft through gears. Connection and disconnection of the power output shaft and the coupling power input shaft are controlled through the synchronizer assembly; when the tractor works at a low gear, the power does not need to be transmitted through a gear pair, and the mechanical transmission efficiency during the low-gear operation is improved; high-gear two-stage gear transmission is achieved in the high-gear state, and the high transmission ratio is achieved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to tractor technical field, concretely relates to a CVT high low gear integral gear transmission structure. BACKGROUND

[0002] The statements in this section merely provide background information related to the utility model and do not necessarily constitute prior art.

[0003] In the traditional process, the high low gear structure of tractor CVT (continuously variable transmission) is usually composed of two parallel shafts, two pairs of gear pairs and a synchronizer; wherein the two transmission shafts are not directly connected, but the power transmission is realized through the two pairs of high gear and low gear; the tractor driver manually operates the synchronizer to complete the high gear and low gear switching according to different working environment and requirements.

[0004] The transmission efficiency of gear pair in the power transmission process is 98.5%, which means that each additional pair of gear pair in the transmission route will reduce the mechanical transmission efficiency of the gearbox to some extent. The load of tractor is large when working in the field, and it needs to be switched to low gear for operation; when the above scheme is adopted, the power transmission of two shafts is realized through a pair of gear pairs in the low gear state, which will affect the mechanical transmission efficiency of tractor when working in the field; and the tractor needs to have a high transmission ratio when in high gear, and it is relatively difficult and inflexible to set the transmission ratio when a pair of gear pairs realizes the high gear change. CONTENT OF THE UTILITY MODEL

[0005] In view of the above problems, the utility model provides a CVT high low gear integral gear transmission structure, which controls the connection or disconnection of the power output shaft and the coupled power input shaft through the synchronizer assembly; realizes that the power does not need to pass through the gear pair to transmit power when the tractor works in low gear, improves the mechanical transmission efficiency of the tractor when working in low gear in the field; in the high gear state, two-stage gear transmission of high gear can be realized, which has a high transmission ratio, can disperse torque and speed, reduces the stress and wear of gear, prolongs the service life, and can also design each transmission ratio respectively, and obtain more accurate transmission ratio after combination.

[0006] In order to realize the above purpose, the utility model takes the following technical scheme:

[0007] A CVT high low gear integral gear transmission structure, comprising a coupled power input shaft and a transmission shaft rotatably connected on a shell; the coupled power input shaft is parallel to the transmission shaft;

[0008] The inside of one end of the coupled power input shaft is rotatably connected with one end of the power output shaft, and the end of the coupled power input shaft is connected with the power output shaft through the synchronizer assembly;

[0009] The transmission shaft is connected with the coupling power input shaft and the power output shaft through gear meshing.

[0010] Preferably, a first low gear is fixedly arranged outside one end of the coupling power input shaft connected with the power output shaft, and the end is provided with a first spline.

[0011] Preferably, a first high gear is rotatably arranged outside one end of the power output shaft away from the coupling power input shaft, and the first high gear is provided with a second spline at the end towards the coupling power input shaft.

[0012] Preferably, a second low gear and a second high gear are fixedly arranged on the transmission shaft.

[0013] Preferably, the second low gear is arranged on one side of the transmission shaft close to the housing, and the second high gear is arranged on the other end of the transmission shaft.

[0014] Preferably, the second low gear is meshed with the first low gear, and the second high gear is meshed with the first high gear.

[0015] Preferably, the coupling power input shaft is rotatably connected with the housing through a first tapered roller bearing and a second tapered roller bearing, and the transmission shaft is rotatably connected with the housing through a cylindrical roller bearing.

[0016] Preferably, the synchronizer assembly is connected with the power output shaft, and the engagement sleeve position of the synchronizer assembly is moved through a shift fork.

[0017] Compared with the prior art, the transmission structure has the advantages and positive effects that:

[0018] The synchronizer assembly is used for controlling the connection or disconnection of the power output shaft and the coupling power input shaft, so that the power does not need to be transmitted through the gear pair when the tractor is working at a low gear, the mechanical transmission efficiency of the tractor in the field at the low gear can be improved, the high gear two-stage gear transmission can be realized in the high gear state, the transmission ratio is high, the torque and the rotating speed can be dispersed, the stress and the wear of the gear are reduced, the service life is prolonged, each gear transmission ratio can be designed respectively, and a more accurate transmission ratio can be obtained after combination. BRIEF DESCRIPTION OF DRAWINGS

[0019] The drawings constituting a part of the specification of the present application are used to provide a further understanding of the present application, and the schematic embodiments of the present application and the description thereof are used to explain the present application, and do not constitute an improper limitation on the present application.

[0020] Figure 1 is a transmission structure schematic view of the embodiment of the present application.

[0021] In the drawings:

[0022] 1, cylindrical roller bearing; 2, second low gear; 3, transmission shaft; 4, second high gear; 5, coupling power input shaft; 6, first tapered roller bearing; 7, second tapered roller bearing; 8, synchronizer assembly; 9, first high gear; 10, power output shaft; 11, shift fork; 12, first low gear. DETAILED DESCRIPTION

[0023] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs.

[0024] The present application will be described in detail below with reference to the accompanying drawings. The CVT high-low gear transmission structure disclosed in the present embodiment, as shown in Figure 1 , includes a coupling power input shaft 5, which is rotatably connected to the housing through a first tapered roller bearing 6 and a second tapered roller bearing 7; as shown in Figure 1 , a first low gear 12 is fixedly arranged on the outer side of one end of the coupling power input shaft 5, and a first spline is also fixedly arranged on this end. It can be understood that the other end of the coupling power input shaft 5 is connected to a power source to introduce power, and the power source can be a common power source in the prior art, such as an engine or a motor. When the coupling power input shaft 5 rotates, the first low gear 12 rotates with it.

[0025] As shown in Figure 1 , one end of the power output shaft 10 extends into the interior of the end of the coupling power input shaft 5 with the first low gear 12 and is rotatably connected to the coupling power input shaft 5; the outer side of the power output shaft 10 is connected to the synchronizer assembly 8; the outer side of the end of the power output shaft 10 away from the coupling power input shaft 5 is rotatably provided with a first high gear 9 through a needle bearing, and a second spline is arranged on the end of the first high gear 9 facing the coupling power input shaft 5. The end of the coupling power input shaft 5 with the first low gear 12 is connected to the power output shaft 10 through the synchronizer assembly 8, and the synchronizer assembly 8 is controlled by the shift fork 11. It can be understood that the synchronizer assembly and the shift fork in the present embodiment are both of the prior art, and the position of the engaging sleeve in the synchronizer assembly is changed by the shift fork to connect or disconnect the first spline on the coupling power input shaft, so as to connect or disconnect the coupling power input shaft 5 and the power output shaft 10. The power output shaft 10 is used to connect the rear axle gear train to provide power for the tractor to move.

[0026] As shown in Figure 1As shown, it also includes a transmission shaft 3, one end of the transmission shaft 3 is rotatably connected with the shell through a cylindrical roller bearing 1. A circle of second low gear 2 and a circle of second high gear 4 are fixedly arranged outside the transmission shaft 3, the second low gear 2 is arranged at the end of the transmission shaft 3 close to the shell, and the second high gear 4 is arranged at the other end of the transmission shaft 3. The first low gear is engaged with the second low gear, and the first high gear is engaged with the second high gear.

[0027] It can be understood that when the coupling power input shaft 5 rotates, the transmission shaft 3 will rotate synchronously under the meshing action of the first low gear and the second low gear.

[0028] Working principle:

[0029] Under low gear working condition of the tractor, the synchronizer assembly is controlled by the shift fork to connect the first spline, so that the power output shaft is connected with the coupling power input shaft, at this time the power and torque provided by the engine are directly transmitted to the rear axle gear through the coupling power input shaft and the power output shaft;

[0030] In this state, the coupling power input shaft and the power output shaft are directly connected through the synchronizer assembly to transmit power, and no longer through gear transmission, which can improve the mechanical transmission efficiency of the tractor in the field under low gear working condition. And the coupling power input shaft drives the transmission shaft to rotate synchronously through the meshing action of the first low gear and the second low gear, which can provide larger output torque and power for other output shafts when the transmission shaft is connected with other output shafts.

[0031] Under high gear working condition, the synchronizer assembly is controlled by the shift fork to connect the second spline, so that the power output shaft is disconnected with the coupling power input shaft, and the first high gear is connected with the power output shaft; the power and torque are transmitted to the second low gear of the transmission shaft through the coupling power input shaft and the first low gear, and then transmitted to the power output shaft through the transmission shaft, the second high gear and the first high gear, and finally transmitted to the rear axle gear.

[0032] In this state, the power provided by the engine realizes one-stage gear transmission through the coupling power input shaft and the low gear shaft, the power is transmitted to the high gear through the transmission shaft, and the high gear and the high gear form two-stage gear transmission. The two-stage gear transmission of the high gear driving wheel can disperse torque and rotate speed, reduce gear stress and wear, and prolong service life; two-stage gear transmission can be used in high gear to design the transmission ratio of each stage respectively, and obtain more accurate transmission ratio after combination.

[0033] The utility model discloses above although the specific embodiment of the utility model has been described in conjunction with the drawing, is not the limit to the protection scope of the utility model, and the person skilled in the art should understand that on the basis of the technical scheme of the utility model, various modifications or deformation that the person skilled in the art can make without paying creative labour are still within the protection scope of the utility model.

Claims

1. A CVT high-low range integral gear drive structure, characterized by, The coupling power input shaft and the transmission shaft are rotatably connected on the shell; The inner end of the coupling power input shaft is rotatably connected with the power output shaft, and the end of the coupling power input shaft is connected with the power output shaft through a synchronizer assembly; The transmission shaft is connected with the coupling power input shaft and the power output shaft through gear engagement.

2. A CVT high-low range gear drive structure as claimed in claim 1, characterized in that, A first low gear is fixedly arranged on the outer side of the end of the coupling power input shaft connected with the power output shaft, and the end is provided with a first spline.

3. A CVT high-low range gear drive structure as claimed in claim 1, wherein, A first high gear is rotatably arranged on the outer side of the end of the power output shaft away from the coupling power input shaft, and the first high gear is provided with a second spline toward the end of the coupling power input shaft.

4. The CVT high-low range gear drive structure of claim 1, wherein, A second low gear and a second high gear are arranged on the transmission shaft.

5. A CVT high-low range gear drive structure as claimed in claim 4, characterized in that, The second low gear is arranged on the end of the transmission shaft close to the shell, and the second high gear is arranged on the other end of the transmission shaft.

6. A CVT high-low range gear drive structure as claimed in claim 4, wherein, The second low gear is engaged with the first low gear, and the second high gear is engaged with the first high gear.

7. A CVT high-low range gear drive structure as claimed in claim 1, wherein, The coupling power input shaft is rotatably connected with the shell through a first tapered roller bearing and a second tapered roller bearing, and the transmission shaft is rotatably connected with the shell through a cylindrical roller bearing.

8. A CVT high-low range gear drive structure as claimed in claim 1, wherein, The synchronizer assembly is connected with the power output shaft, and the engagement sleeve position of the synchronizer assembly is moved through a shift fork.

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