CN113915327B

CN113915327B - Gear shifting control method of gearbox clutch and gearbox

Info

Publication number: CN113915327B
Application number: CN202111139615.9A
Authority: CN
Inventors: 刘志强; 吴志广; 褚伟; 于伟波; 王程宇
Original assignee: Changzhou Huachuang Aviation Technology Co ltd; Jiangsu Changfa Agricultural Equipment Co Ltd
Current assignee: Changzhou Huachuang Aviation Technology Co ltd
Priority date: 2021-09-28
Filing date: 2021-09-28
Publication date: 2023-02-17
Anticipated expiration: 2041-09-28
Also published as: CN113915327A

Abstract

The invention provides a gear shifting control method for a gearbox clutch. The shift control method includes: executing gear shifting operation, and synchronously combining the second clutch while disengaging the first clutch; the rotating speed sensor collects rotating speed values of the first clutch and the second clutch in the sliding friction process in real time, and a torque value is calculated through the rotating speed values; the TCU receives the torque value acquired by the rotating speed sensor and analyzes the torque value to obtain a corresponding gain coefficient, and the TCU adjusts the torque value of the clutch in the friction sliding process by taking the gain coefficient as a multiple. In the process of disengaging the first clutch and combining the second clutch, the torque of the first clutch and the torque of the second clutch in the friction sliding process are adjusted through the gain coefficients corresponding to the torque values of the first clutch and the second clutch in the friction sliding process, and stable gear shifting of power is achieved.

Description

Gear shifting control method of gearbox clutch and gearbox

Technical Field

The invention relates to the technical field of gearboxes, and particularly provides a gearbox with a gearbox clutch and a gear shifting control method.

Background

With the development of industry, automatic gear shifting is more and more favored by consumers. Compared with the manual gear shifting operation which needs frequent gear shifting, the automatic gear shifting device is easy to fatigue a driver, further influences the driving safety, is light in automatic gear shifting operation and has good self-adaptability, and the service lives of an engine and a gearbox are greatly prolonged. The automatic gear shifting changes the transmission ratio by opening and combining the clutch, and finishes the gear shifting control process.

The automatic shifting structure includes gear elements and clutches, and shifting from one speed ratio to another speed ratio is automatically performed by the automatic shifting structure. During a gear shift, the clutch selectively couples the input and output shafts of the transmission to achieve a desired output speed ratio. Clutch engagement and disengagement is typically achieved by the controlled application of fluid pressure that moves a clutch piston from an initial position into or out of engagement with a clutch pack. Due to the fact that the running working conditions of the vehicle are complex and changeable, gear shifting impact, shaking or jerking are easily caused in the process that the clutch is disengaged and combined, further excessive belt row loss is caused, and fuel enthusiasm of the whole vehicle is influenced. It is therefore desirable to provide a transmission clutch shift control method to address the above problems.

Disclosure of Invention

The invention aims to provide a gear shifting control method of a gearbox clutch, which overcomes the defects of easy gear shifting impact, shaking or pause in the gear shifting process in the prior art. By adopting the gear shifting control method, the problem of gear shifting impact in the gear shifting process is solved, and simple, efficient and smooth gear shifting control of the gearbox clutch is realized.

The invention provides a gear shifting control method of a clutch of a gearbox, wherein the gearbox comprises a first clutch, a second clutch, an electromagnetic valve and a rotating speed sensor, and the gear shifting control method comprises the following steps:

executing gear shifting operation, and synchronously combining the second clutch while disengaging the first clutch;

the method comprises the following steps that a rotation speed sensor collects torque values of a first clutch and a second clutch in a sliding friction process in real time;

the TCU receives a torque value calculated by the rotating speed value acquired by the rotating speed sensor and analyzes the torque value to obtain a corresponding gain coefficient, and the TCU adjusts the torque value of the clutch in the slipping process by taking the gain coefficient as a multiple;

in the process of disengaging the first clutch and combining the second clutch, the torque of the first clutch and the torque of the second clutch in the friction sliding process are adjusted through the gain coefficients corresponding to the torque values of the first clutch and the second clutch in the friction sliding process, and stable gear shifting of power is achieved.

The disengaging process of the first clutch and the combining process of the second clutch are controlled by the hydraulic mechanism, and the electromagnetic valve adjusts the output current by taking the gain coefficient as the speed doubling factor so as to adjust the oil pressure of the hydraulic mechanism, so that the torque of the first clutch and the torque of the second clutch in the sliding friction process are controlled.

Further, the transmission clutch shift control method includes a heavy load start mode and a light load start mode during start:

under the light-load starting mode, the second clutch connects the second driving shaft and the second driven shaft for power transmission;

in the heavy-load starting mode, the second clutch connects the second driving shaft and the second driven shaft for power transmission, meanwhile, the third clutch connects the third driving shaft and the third driven shaft for power transmission, when the target rotating speed is reached, the third clutch is gradually separated to be disconnected, and the second clutch separately connects the second driving shaft and the second driven shaft for power transmission.

Further, in the heavy load starting mode, an output speed of the third clutch when connecting the third driving shaft and the third driven shaft is greater than an output speed of the second clutch when connecting the second driving shaft and the second driven shaft.

Further, the gearbox includes power input shaft, PTO output shaft, power output shaft, jackshaft, intermediate gear set, power output gear set, first drive shaft, first driven shaft, first clutch, first driven gear set, second gear set, the second drive shaft, the second driven shaft, the second clutch, second driven gear set, the third drive shaft, the third driven shaft, the third clutch, the third driven gear set, reverse gear set, reverse gear drive shaft, reverse gear driven shaft, reverse gear clutch, reverse gear jackshaft, reverse gear driven gear set, crawl gear set, crawl gear shaft, four-wheel drive gear set, four-wheel drive shaft, four-wheel drive driven shaft and four-wheel drive clutch.

Further, the power input shaft is connected with an engine to input engine power; the PTO output shaft and the power input shaft are coaxially arranged; the power output shaft outputs power after gear shifting and speed changing; the intermediate shaft is sleeved on the PTO output shaft in an empty mode.

Further, the intermediate gear set is arranged on the intermediate shaft; the power output gear set is arranged on the power output shaft and is meshed with the intermediate gear set to output power.

Further, the first driving shaft is connected with the power input shaft through the first gear set for power transmission; the first driven shaft and the first driving shaft are coaxially arranged; the first clutch is arranged between the first driving shaft and the first driven shaft and used for connecting or disconnecting power transmission; the first driven gear set is arranged on the first driven shaft and connected with the intermediate gear set for power transmission.

Further, the second driving shaft is connected with the power input shaft through the second gear set for power transmission; the second driven shaft and the second driving shaft are coaxially arranged; the second clutch is arranged between the second driving shaft and the second driven shaft and used for connecting or disconnecting power transmission; the second driven gear set is arranged on the second driven shaft and is connected with the intermediate gear set for power transmission.

Further, the third driving shaft is connected with the power input shaft through the third gear set for power transmission; the third driven shaft and the third driving shaft are coaxially arranged; the third clutch is arranged between the third driving shaft and the third driven shaft and used for connecting or disconnecting power transmission; the third driven gear set is arranged on the third driven shaft and is connected with the intermediate gear set for power transmission.

Further, the reverse gear driving shaft is connected with the power input shaft through the reverse gear set to perform power transmission; the reverse gear driven shaft and the reverse gear driving shaft are coaxially arranged; the reverse gear clutch is arranged between the reverse gear driving shaft and the reverse gear driven shaft and used for connecting or disconnecting power transmission; the reverse gear intermediate shaft is arranged between the reverse gear driving shaft and the power input shaft; the reverse gear driven gear set is arranged on the reverse gear driven shaft and connected with the intermediate gear set for power transmission.

Furthermore, the crawling gear shaft is connected with the power output shaft through the crawling gear group to transmit power, and the crawling gear shaft is arranged in parallel with the power output shaft.

Furthermore, the four-wheel driving shaft is connected with the power output shaft through the four-wheel driving gear set to transmit power, so that four-wheel driving power output is realized;

further, the four-wheel drive driven shaft and the four-wheel drive shaft are coaxially arranged; the four-wheel drive clutch is arranged between the four-wheel drive shaft and the four-wheel drive driven shaft and used for connecting or disconnecting four-wheel drive power transmission.

Further, the first gear set comprises a first gear and a fourth gear which are arranged on the power input shaft, a seventh gear and an eighth gear which are arranged on the first driving shaft, and a first synchronizer which is arranged between the seventh gear and the eighth gear and arranged on the first driving shaft; the first gear is in constant mesh with the seventh gear, and the fourth gear is in constant mesh with the eighth gear.

Further, when the first synchronizer is shifted to be connected with the No. seven gear, the first driving shaft outputs the rotating speed to the first driven shaft at the transmission ratio between the No. one gear and the No. seven gear;

when the first synchronizer is connected with the eighth gear in a shifting mode, the first driving shaft outputs rotating speed to the first driven shaft in a transmission ratio between the fourth gear and the eighth gear.

Further, the second gear set comprises a second gear and a fifth gear which are arranged on the power input shaft, a ninth gear and a tenth gear which are arranged on the second driving shaft, and a second synchronizer which is arranged between the ninth gear and the tenth gear and is arranged on the second driving shaft; the second gear is in constant mesh with the ninth gear, and the fifth gear is in constant mesh with the tenth gear.

Further, when the second synchronizer is shifted to be connected with the gear No. nine, the second driving shaft outputs the rotating speed to the second driven shaft at the transmission ratio between the gear No. two and the gear No. nine;

when the second synchronizer is connected with the No. ten gear in a shifting mode, the second driving shaft outputs rotating speed to the second driven shaft in a transmission ratio between the No. five gear and the No. ten gear.

Further, in a light-load starting mode, the second synchronizer is shifted to be connected with the tenth gear, and the second driving shaft outputs the rotating speed to the second driven shaft according to the transmission ratio between the fifth gear and the tenth gear.

Further, the third gear set comprises a third gear and a sixth gear which are arranged on the power input shaft, an eleventh gear and a twelfth gear which are arranged on the third driving shaft, and a third synchronizer which is arranged between the eleventh gear and the twelfth gear and is arranged on the third driving shaft; the third gear is in constant mesh with the eleventh gear, and the sixth gear is in constant mesh with the twelfth gear.

Further, when the third synchronizer is shifted to be connected with the eleventh gear, the third driving shaft outputs the rotating speed to the third driven shaft at the transmission ratio between the third gear and the eleventh gear;

when the third synchronizer is shifted to be connected with the twelfth gear, the third driving shaft outputs rotating speed to the third driven shaft at the transmission ratio between the sixth gear and the twelfth gear.

Further, in a heavy-duty starting mode, the second synchronizer is shifted to be connected with the tenth gear, and the second driving shaft outputs the rotating speed to the second driven shaft at the transmission ratio between the fifth gear and the tenth gear;

meanwhile, the third synchronizer is connected with the No. twelve gear in a shifting mode, and the third driving shaft outputs rotating speed to the third driven shaft according to the transmission ratio between the No. six gear and the No. twelve gear.

Further, the reverse gear set includes a fifteen-and a sixteen-gear disposed on the reverse drive shaft, a thirteen-gear disposed on the reverse countershaft and between the first-gear and the fifteenth-gear, a fourteen-gear disposed on the reverse countershaft and between the fourth-gear and the sixteenth-gear, and a fourth synchronizer disposed between the fifteen-and sixteenth-gear and on the reverse drive shaft; the thirteen-gear is in constant mesh with the first gear and the fifteen-gear at the same time, and the fourteen-gear is in constant mesh with the fourth gear and the sixteen-gear at the same time.

Further, when the fourth synchronizer is shifted to be connected with the fifteen-gear, the reverse driving shaft outputs the rotating speed to the reverse driven shaft at the transmission ratio among the first gear, the thirteen gear and the fifteen gear;

when the fourth synchronizer is connected with the sixteenth gear in a shifting mode, the reverse driving shaft outputs rotating speed to the reverse driven shaft in a transmission ratio among the fourth gear, the fourteenth gear and the sixteenth gear.

Further, the power output gear set comprises a thirty-first gear which is sleeved on the power output shaft in an empty mode, a thirty-second gear which is sleeved on the power output shaft in an empty mode, an eleventh synchronizer which is arranged on the left side of the thirty-first gear, and a twelfth synchronizer which is arranged on the right side of the thirty-second gear.

Further, when the eleventh synchronizer is connected with the thirty-second gear, the twelfth synchronizer is separated from the thirty-second gear, and the power output shaft outputs the rotating speed through the thirty-second gear;

when the twelfth synchronizer is connected with the thirty-two gear, the eleventh synchronizer is separated from the thirty-two gear, and the power output shaft outputs the rotating speed through the thirty-two gear.

Further, the intermediate gear set comprises a seventeen gear and a nineteen gear which are fixedly connected with the intermediate shaft, an eighteen gear which is arranged between the seventeen gear and the nineteen gear and is sleeved on the intermediate shaft in an empty mode, and a fifth synchronizer which is arranged between the eighteen gear and the nineteen gear and is arranged on the intermediate shaft.

Further, the eighteen-gauge gear is in constant mesh with the thirty-gauge gear, and the nineteen-gauge gear is in constant mesh with the thirty-two-gauge gear;

when the fifth synchronizer is connected with the eighteen gear, the eleventh synchronizer is connected with the thirty gear, and the power output shaft outputs the rotating speed through the transmission ratio between the eighteen gear and the thirty gear;

when the fifth synchronizer is shifted to be separated from the eighteen gears, the twelfth synchronizer is connected with the thirty-two gears, and the power output shaft outputs the rotating speed through the transmission ratio between the nineteen gears and the thirty-two gears.

Further, the first driven gear set comprises a twenty-first gear and a twenty-first gear which are freely sleeved on the first driven shaft, and a sixth synchronizer which is arranged between the twenty-first gear and arranged on the first driven shaft; the twenty-first gear is normally meshed with the eighteen gear.

When the sixth synchronizer is shifted to be connected with the No. twenty gear, the intermediate shaft outputs the rotating speed through the transmission ratio between the No. seventeen gear and the No. twenty gear;

when the sixth synchronizer is shifted to be connected with the twenty-first gear, the intermediate shaft outputs the rotating speed through the transmission ratio between the eighteen gear and the twenty-first gear.

Further, the second driven gear set comprises a twenty-second gear and a twenty-third gear which are sleeved on the second driven shaft in a hollow manner, and a seventh synchronizer which is arranged between the twenty-second gear and the twenty-third gear and arranged on the second driven shaft; the twenty-two gear is in constant mesh with the seventeen gear, and the twenty-three gear is in constant mesh with the eighteen gear.

Further, when the seventh synchronizer is shifted to be connected with the twenty-two second gear, the intermediate shaft outputs the rotating speed through the transmission ratio between the seventeen second gear and the twenty-two second gear;

when the seventh synchronizer is shifted to be connected with the twenty-third gear, the intermediate shaft outputs the rotating speed through the transmission ratio between the eighteen gear and the twenty-third gear.

Further, the third driven gear set comprises a twenty-four gear and a twenty-five gear which are sleeved on the third driven shaft in a hollow manner, and an eighth synchronizer which is arranged between the twenty-four gear and the twenty-five gear and arranged on the third driven shaft; the twenty-four gears are normally meshed with the seventeen gears, and the twenty-five gears are normally meshed with the eighteen gears.

Further, when the eighth synchronizer is shifted to be connected with the twenty-four gears, the intermediate shaft outputs the rotating speed through the transmission ratio between the seventeen gears and the twenty-four gears;

when the eighth synchronizer is shifted to be connected with the twenty-fifth gear, the intermediate shaft outputs the rotating speed through the transmission ratio between the eighteen gear and the twenty-fifth gear.

Further, in a light-load starting mode, a second clutch is connected, the second synchronizer is shifted to be connected with the tenth gear, the second driving shaft outputs rotating speed to the second driven shaft according to the transmission ratio between the fifth gear and the tenth gear, the seventh synchronizer is shifted to be connected with the twenty-second gear, the intermediate shaft outputs rotating speed according to the transmission ratio between the seventeen gear and the twenty-second gear, the fifth synchronizer is shifted to be separated from the eighteenth gear, at the moment, the twelfth synchronizer is connected with the thirty-second gear, and the power output shaft outputs rotating speed according to the transmission ratio between the nineteen gear and the thirty-second gear to realize starting.

Further, in a heavy-load starting mode, while the power is transmitted in the light-load starting mode, a third clutch is connected, the third synchronizer is switched to be connected with the twelfth gear, the third driving shaft outputs the rotating speed to the third driven shaft at the transmission ratio between the sixth gear and the twelfth gear, the eighth synchronizer is switched to be connected with the twenty-four gear, the middle shaft outputs the rotating speed through the transmission ratio between the seventeen gear and the twenty-four gear, so that the output torque of the middle shaft is improved, and the nineteen gear and the thirty-two gear output the rotating speed to the power output shaft at a stronger torque to realize starting;

further, when the target rotation speed is reached, the third clutch is gradually disengaged to be disconnected, and the second clutch solely connects the second drive shaft and the second driven shaft for power transmission in the light-load starting mode.

Furthermore, the crawling gear set comprises a thirty-one gear which is arranged on the power output shaft and is fixedly connected with the thirty-two gear, a twenty-eight gear which is sleeved on the power output shaft in an empty mode, a tenth synchronizer which is arranged on the power output shaft, a thirty-three gear which is arranged on the crawling gear shaft and is fixedly connected with the crawling gear shaft, and a thirty-five gear which is arranged on the crawling gear shaft and is fixedly connected with the crawling gear shaft; the thirty-first gear is in constant mesh with a thirty-fifth gear, and the twenty-eight gear is in constant mesh with the thirty-third gear.

Furthermore, when the crawling gear group works, the twelfth synchronizer is separated from the thirty-two gears, when the tenth synchronizer is connected with the twenty-eight gears, the crawling gear shaft outputs the rotating speed through the transmission ratio between the thirty-first gear and the thirty-five gears, and then the power output shaft outputs the rotating speed through the transmission ratio between the thirty-third gear and the twenty-eight gears.

Furthermore, the four-wheel drive gear set comprises a twenty-ninth gear which is arranged on the power output shaft and is fixedly connected with the power output shaft, a thirty-sixth gear which is fixedly connected with the four-wheel drive shaft, and a thirty-fourth gear which is arranged between the twenty-ninth gear and the thirty-sixth gear and is sleeved on the crawling gear shaft in a hollow manner;

the twenty-ninth gear is in constant mesh with the thirty-fourth gear, the thirty-fourth gear is in constant mesh with the thirty-sixth gear, and the four-wheel driving shaft outputs the rotating speed through the transmission ratio among the twenty-ninth gear, the thirty-fourth gear and the thirty-sixth gear.

Further, when the four-wheel drive clutch is connected, the four-wheel drive shaft transmits the rotational speed to the four-wheel drive driven shaft, which in turn outputs four-wheel drive.

Further, the invention also provides a gearbox, which comprises the gearbox clutch gear-shifting control method.

The gear shifting control method of the gearbox clutch and the gearbox provided by the invention can bring at least one of the following beneficial effects:

according to the gear shifting control method for the gearbox clutch, the gain coefficient is introduced in the process of clutch disengagement and clutch combination, the problem of gear shifting impact in the gear shifting process is solved, and simple, efficient and smooth gear shifting control of the gearbox clutch is achieved.

Drawings

The invention is described in further detail below with reference to the following figures and detailed description:

FIG. 1 is a diagrammatic illustration of the transmission principle of the transmission of the present invention;

FIG. 2 is a left side view of the transmission of the present invention;

FIG. 3 isbase:Sub>A cross-sectional view taken along line A-A of FIG. 2;

FIG. 4 is a sectional view taken along line B-B of FIG. 2;

FIG. 5 is a cross-sectional view taken along line C-C of FIG. 2;

fig. 6 is a comparison between the theoretical output current of the solenoid valve and the actual output current adjusted at a gain factor of multiple speed during the disengagement of the first clutch F1, where the dotted line is the theoretical output current and the solid line is the actual output current;

FIG. 7 is a comparison between the theoretical output current of the solenoid valve and the actual output current adjusted by the gain factor as the speed during the engagement of the second clutch F2;

FIG. 8 is a graph showing the gain factor of the first clutch F1 as a function of torque during disengagement of the first clutch F1 in the embodiment;

FIG. 9 is a graph showing the gain factor of the second clutch F2 as a function of torque change during the synchronous engagement of the second clutch F2 while the first clutch F1 is engaged in accordance with the embodiment;

FIG. 10 is a clutch engagement current profile for the light load launch mode of the present invention;

FIG. 11 is a graph showing the variation of clutch engagement current during a heavy load launch mode according to the present invention.

The reference numbers indicate:

a1 — a first drive shaft; a2 — a second drive shaft; a3-a third drive shaft; a4-reverse gear drive shaft; a 1-a first driven shaft; a 2-a second driven shaft; a 3-a third driven shaft; a 4-reverse gear driven shaft; r-reverse countershaft; an M-power input shaft; m-middle shaft; an O-power output shaft; g-a four-wheel drive axle; g-four wheel drive driven shaft; p-creeper shaft; d-a reverse gear set; k-intermediate gear set; n1-a first driven gear set; n2-a second driven gear set; n3-a third driven gear set; a T-power output gear set; an H-four wheel drive gear set; a U-crawling gear group; s1, a first synchronizer; s2-a second synchronizer; s3, a third synchronizer; s4-a fourth synchronizer; s5, a fifth synchronizer; s6-a sixth synchronizer; s7-a seventh synchronizer; s8-an eighth synchronizer; s10-a tenth synchronizer; s11-an eleventh synchronizer; s12-a twelfth synchronizer; f1-first clutch; f2-a second clutch; f3-a third clutch; FR-reverse clutch.

Detailed Description

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

For the sake of simplicity, the drawings only schematically show the parts relevant to the present invention, and they do not represent the actual structure as a product. In addition, in order to make the drawings concise and understandable, components having the same structure or function in some of the drawings are only schematically illustrated or only labeled. In this document, "one" means not only "only one" but also a case of "more than one".

It should be further understood that the term "and/or" as used in this specification and the appended claims refers to any and all possible combinations of one or more of the associated listed items and includes such combinations.

In this context, it is to be understood that, unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly and may include, for example, a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in a specific case to those of ordinary skill in the art.

In addition, in the description of the present application, the terms "first", "second", and the like are used only for distinguishing the description, and are not intended to indicate or imply relative importance.

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following description will be made with reference to the accompanying drawings. It is obvious that the drawings in the following description are only some examples of the invention, and that for a person skilled in the art, without inventive effort, other drawings and embodiments can be derived from them.

Referring to fig. 1 and 5, in an embodiment, there is provided a transmission 100 for a tractor, including: the power output mechanism comprises a power input shaft M, a power output shaft O, an intermediate shaft M, an intermediate gear set K and a power output gear set T. The power input shaft M is connected with an engine to output power of the engine, and simultaneously serves as a PTO output shaft; the power output shaft O finally outputs the power after gear shifting and speed changing; the intermediate shaft m is sleeved on the PTO output shaft in an empty way; the intermediate gear set is arranged on the intermediate shaft; the power output gear set T is arranged on the power output shaft M and is meshed with the middle gear set K to output power.

The transmission 100 further includes a first gear set, a first driving shaft A1, a first driven shaft A1, and a first driven gear set N1. The first driving shaft A1 is connected with the power input shaft M through the first gear set for power transmission; the first driven shaft A1 and the first driving shaft A1 are coaxially arranged; the first driven gear set N1 is arranged on the first driven shaft a1 and is connected with the intermediate gear set K for power transmission.

The transmission 100 further includes a second gear set, a second driving shaft A2, a second driven shaft A2, and a second driven gear set N2. The second driving shaft A2 is connected with the power input shaft M through the second gear set to perform power transmission; the second driven shaft A2 is arranged coaxially with the second driving shaft A2; the second driven gear set N2 is arranged on the second driven shaft a2 and is connected with the intermediate gear set K for power transmission.

The transmission 100 further includes a third gear set, a third driving shaft A3, a third driven shaft A3, and a third driven gear set N3. The third driving shaft A3 is connected with the power input shaft M through the third gear set for power transmission; the third driven shaft A3 is arranged coaxially with the third driving shaft A3; the third driven gear set N3 is arranged on the third driven shaft a3 and is connected with the intermediate gear set K for power transmission.

The transmission 100 also includes a reverse gear set D, a reverse drive shaft A4, a reverse driven shaft A4, a reverse countershaft R, and a reverse driven gear set E. The reverse driving shaft A4 is connected with the power input shaft M through the reverse gear set D to transmit power, and the reverse driven shaft A4 and the reverse driving shaft A4 are coaxially arranged; the reverse gear intermediate shaft R is arranged between the reverse gear driving shaft A4 and the power input shaft M; the reverse gear driven gear set E is arranged on the reverse gear driven shaft a4 and is connected with the intermediate gear set K for power transmission.

The transmission 100 further includes a first clutch F1, a second clutch F2, and a third clutch F3. The first clutch F1 is interposed between the first driving shaft A1 and the first driven shaft A1 to connect or disconnect power transmission; the second clutch F2 is interposed between the second driving shaft A2 and the second driven shaft A2 to connect or disconnect power transmission; the third clutch F3 is interposed between the third driving shaft A3 and the third driven shaft A3 to connect or disconnect power transmission.

The transmission 100 further includes a reverse clutch FR interposed between the reverse drive shaft A4 and the reverse driven shaft A4 to connect or disconnect power transmission.

Referring to fig. 2, the first driving shaft A1, the first driven shaft A1, the second driving shaft A2, the second driven shaft A2, the third driving shaft A3, the third driven shaft A3, the reverse driving shaft A4, the reverse intermediate shaft R and the reverse driven shaft A4 are all arranged in parallel.

And the connecting lines of the axle centers of the first driving shaft A1, the second driving shaft A2, the third driving shaft A3 and the reverse gear driving shaft A4 form a trapezoid.

The transmission device 100 further comprises a crawling gear wheel set U and a crawling gear shaft P, the crawling gear shaft P is connected with the power output shaft O through the crawling gear wheel set U to transmit power, and the crawling gear shaft P is arranged in parallel with the power output shaft O.

The transmission 100 further includes a four-wheel drive gear set H, a four-wheel drive shaft G, a four-wheel drive driven shaft G, and a four-wheel drive clutch F4. The four-wheel driving shaft G realizes four-wheel drive output through the four-wheel driving gear set H; the four-wheel drive driven shaft G and the four-wheel drive shaft G are coaxially arranged; the four-wheel drive clutch F4 is disposed between the four-wheel drive shaft G and the four-wheel drive driven shaft G to connect or disconnect four-wheel drive power transmission.

This does not exclude the possibility that the transmission 100 may comprise, for example, a pair of gears in the first gear set, which are connected by a flexible transmission member, such as a chain, and configured to produce the same transmission ratio as in the first gear set.

The transmission device 100 further includes a TCU and an electromagnetic valve, the transmission device 100 controls a hydraulic system to work through the TCU to realize the cooperation of the synchronizer and the clutch, so as to realize a shift operation, and the shift operation is described below by taking the shift process of the first clutch and the second clutch as an example. The shift control method specifically includes:

executing a gear shifting operation, wherein the first clutch F1 is disengaged and simultaneously the second clutch F2 is synchronously engaged;

the method comprises the following steps that a rotation speed sensor collects torque values of a first clutch F1 and a second clutch F2 in a sliding friction process in real time, and the torque values are calculated through the rotation speed values;

the TCU receives a torque value calculated by the rotating speed value acquired by the rotating speed sensor and analyzes the torque value to obtain a corresponding gain coefficient, and the TCU further adjusts the torque values of the first clutch F1 and the second clutch F2 in the sliding friction process by taking the gain coefficient as a multiple;

in the process of disengaging the first clutch F1 and combining the second clutch F2, the torque of the first clutch F1 and the torque of the second clutch F2 in the friction sliding process are adjusted through the gain coefficients corresponding to the torque values of the first clutch F1 and the second clutch F2 in the friction sliding process, and therefore smooth shifting of power is achieved.

The disengaging process of the first clutch F1 and the combining process of the second clutch F2 are controlled by the hydraulic mechanism, and the electromagnetic valve adjusts the magnitude of the output current by taking the gain coefficient as the speed doubling factor so as to adjust the magnitude of the oil pressure of the hydraulic mechanism, thereby controlling the magnitude of the torque of the first clutch F1 and the second clutch F2 in the friction sliding process.

Referring to fig. 6, fig. 6 is a comparison between the theoretical output current of the solenoid valve and the actual output current adjusted by the gain factor at the speed doubling time during the disengagement of the first clutch F1, where the dotted line is the theoretical output current and the solid line is the actual output current. In the stage from point 1 to point 2, the electromagnetic valve provides stable current to control the hydraulic mechanism to charge oil, and point 2 is the initial disengagement point of the first clutch F1; the stage from the point 2 to the point 3 is a slipping stage of the first clutch F1, the point 3 is a releasing completion point of the first clutch F1, after the point 3, the first clutch F1 does not transmit torque any more, and the first driving shaft A1 does not drive the first driven shaft A1 to synchronously rotate any more; the electromagnetic valve does not provide current any more from 3 points, and the hydraulic mechanism unloads oil.

Referring to fig. 7, fig. 7 is a comparison between the theoretical output current of the solenoid valve and the actual output current adjusted by the gain factor at the speed doubling speed during the engagement of the second clutch F2. Wherein the dotted line is the theoretical output current and the solid line is the actual output current. At the stage from 1 point to 2 points, the electromagnetic valve rapidly provides stable current to control the hydraulic mechanism to fill oil, and after the oil filling is finished, the electromagnetic valve rapidly reduces the current value at the point 2; in the stage from 3 to 4, the current value is increased by the electromagnetic valve, and the second clutch F2 enters the combined preposed stage; the point 4 is the combination starting point of the second clutch F2, the stage from the point 4 to the point 5 is the sliding friction stage of the second clutch F2, the point 5 is the combination finishing point of the second clutch F2, and the second driving shaft A2 starts to drive the second driven shaft A2 to synchronously rotate; in the stage from 5 to 6, the stage from 6 to 7 and the stage from 7 to 8, the solenoid valve further increases the actual output current by taking the gain factor as the speed doubling factor, and increases the combination torque of the second clutch F2 to reach the preset value so as to realize the stable transmission of the power.

It should be noted that, in the present embodiment, the disengagement completion point time of the first clutch F1 is the same as the engagement completion point time of the second clutch F2, and in other embodiments, the disengagement completion point time of the first clutch F1 may be earlier than the engagement completion point time of the second clutch F2, but the disengagement completion point time of the first clutch F1 may not be later than the engagement completion point time of the second clutch F2.

Referring to fig. 8, fig. 8 shows the gain factor of the first clutch F1 as a function of torque during disengagement of the first clutch F1 in the embodiment.

Referring to fig. 9, fig. 9 shows a relationship in which the gain factor of the second clutch F2 is changed with a change in torque during the synchronous engagement of the second clutch F2 while the first clutch F1 is engaged in the embodiment.

Synchronizers and clutches are devices known to those skilled in the art and therefore will not be described further and will neither be described nor shown in the specification. The clutch is not shown in fig. 3 and 4, and in practical applications, the clutch is provided between the drive shaft and the driven shaft.

Because the TCU and hydraulic systems are of the type known to those skilled in the art, they are neither described nor shown.

Referring to fig. 10 and 11, the transmission 100 of the present embodiment includes a heavy-load start mode and a light-load start mode during the start process:

in a light-load starting mode, the second clutch F2 connects the second driving shaft and the second driven shaft for power transmission;

in the heavy-load starting mode, the second clutch F2 connects the second driving shaft A2 and the second driven shaft A2 for power transmission, meanwhile, the third clutch F3 connects the third driving shaft A3 and the third driven shaft A3 for power transmission, when the target rotating speed is reached, the third clutch F3 is gradually separated to be disconnected, and the second clutch F2 alone connects the second driving shaft A2 and the second driven shaft A2 for power transmission.

In the heavy-duty starting mode, the output speed of the third clutch F3 connecting the third driving shaft A3 and the third driven shaft A3 is greater than the output speed of the second clutch F2 connecting the second driving shaft A2 and the second driven shaft A2. In the present embodiment, in the heavy-duty start mode, the second clutch F2 connects the second drive shaft A2 and the second driven shaft A2 for power transmission, and the third clutch F3 connects the third drive shaft A3 and the third driven shaft A3 for power transmission, and when the target rotation speed is reached, the third clutch F3 is gradually disengaged to be disengaged. In other embodiments, the heavy-duty start mode may also be implemented by a combination of other shifting clutches.

The following specifically explains the shift transmission line of the transmission 100 in the present embodiment. The first gear set comprises a first gear 1 and a fourth gear 4 which are arranged on the power input shaft M, a seventh gear 7 and an eighth gear 8 which are arranged on the first driving shaft A1, and a first synchronizer S1 which is arranged between the seventh gear 7 and the eighth gear 8; the first gear 1 is in constant mesh with the seventh gear 7, and the fourth gear 4 is in constant mesh with the eighth gear 8.

When the first synchronizer S1 is shifted to be connected with the seventh gear 7, the first driving shaft A1 outputs a rotation speed to the first driven shaft A1 at a transmission ratio between the first gear 1 and the seventh gear 7; when the first synchronizer S1 is shifted to be connected with the eighth gear 8, the first driving shaft A1 outputs a rotation speed to the first driven shaft A1 at a transmission ratio between the fourth gear 4 and the eighth gear 8.

The second gear set comprises a second gear 2 and a fifth gear 5 which are arranged on the power input shaft M, a ninth gear 9 and a tenth gear 10 which are arranged on the second driving shaft A2, and a second synchronizer S2 which is arranged between the ninth gear 9 and the tenth gear 10; the second gear 2 is in constant mesh with the ninth gear 9, and the fifth gear 5 is in constant mesh with the tenth gear 10.

When the second synchronizer S2 is shifted to be connected with the ninth gear 9, the second driving shaft A2 outputs a rotation speed to the second driven shaft A2 at a transmission ratio between the second gear 2 and the ninth gear 9; when the second synchronizer S2 is shifted to be connected with the ten-gear 10, the second driving shaft A2 outputs a rotational speed to the second driven shaft A2 at a transmission ratio between the fifth gear 5 and the ten-gear 10.

In the light load starting mode, the second synchronizer S2 is shifted to be connected with the tenth gear 10, and the second driving shaft A2 outputs the rotating speed to the second driven shaft A2 at the transmission ratio between the fifth gear 5 and the tenth gear 10.

The third gear set includes a third gear 3 and a sixth gear 6 disposed on the power input shaft M, an eleventh gear 11 and a twelfth gear 12 disposed on the third driving shaft A3, and a third synchronizer S3 disposed between the eleventh gear 11 and the twelfth gear 12; the third gear 3 is in constant mesh with the eleventh gear 11, and the sixth gear 6 is in constant mesh with the twelfth gear 12.

When the third synchronizer S3 is shifted to be connected to the eleventh gear 11, the third driving shaft A3 outputs a rotational speed to the third driven shaft A3 at a transmission ratio between the third gear 3 and the eleventh gear 11; when the third synchronizer S3 is shifted to be connected to the twelfth gear 12, the third driving shaft A3 outputs a rotational speed to the third driven shaft A3 at a gear ratio between the sixth gear 6 and the twelfth gear 12.

In a heavy-load starting mode, the second synchronizer S2 is shifted to be connected with the ten-gear 10, and the second driving shaft A2 outputs a rotating speed to the second driven shaft A2 at a transmission ratio between the fifth gear 5 and the ten-gear 10;

meanwhile, the third synchronizer S3 is shifted to be connected to the twelfth gear 12, and the third driving shaft A3 outputs the rotational speed to the third driven shaft A3 at the transmission ratio between the sixth gear 6 and the twelfth gear 12.

The reverse gear set D includes a fifteenth gear 15 and a sixteenth gear 16 disposed on the reverse drive shaft A4, a thirteenth gear 13 disposed on the reverse countershaft R between the first gear 1 and the fifteenth gear 15, a fourteenth gear 14 disposed on the reverse countershaft R between the fourth gear 4 and the sixteenth gear 16, and a fourth synchronizer S4 disposed between the fifteenth gear 15 and the sixteenth gear 16; the thirteenth gear 13 is in constant mesh with the first gear 1 and the fifteenth gear 15 at the same time, and the fourteenth gear 14 is in constant mesh with the fourth gear 4 and the sixteenth gear 16 at the same time.

When the fourth synchronizer S4 is shifted to be connected with the fifteenth gear 15, the reverse drive shaft A4 outputs a rotation speed to the reverse driven shaft A4 at a transmission ratio among the first gear 1, the thirteenth gear 13 and the fifteenth gear 15; when the fourth synchronizer S4 is shifted to be connected with the sixteenth gear 16, the reverse drive shaft A4 outputs a rotational speed to the reverse driven shaft A4 at a transmission ratio among the fourth gear 4, the fourteenth gear 14 and the sixteenth gear 16.

The power output gear set O comprises a thirty-second gear 30 which is sleeved on the power output shaft O in an empty mode, a thirty-second gear 32 which is sleeved on the power output shaft O in an empty mode, an eleventh synchronizer S11 which is arranged on the left side of the thirty-second gear 30 and a twelfth synchronizer S12 which is arranged on the right side of the thirty-second gear 32. The "left" and "right" in this embodiment are explained with the directions defined in fig. 2.

When the eleventh synchronizer S11 is connected with the thirty-second gear 30, the twelfth synchronizer S12 is disconnected from the thirty-second gear 32, and the power output shaft O outputs the rotation speed through the thirty-second gear 30; when the twelfth synchronizer S12 is connected to the thirty-two second gear 32, the eleventh synchronizer S11 is disconnected from the thirty second gear 30, and the power output shaft O outputs a rotation speed through the thirty-two second gear 32.

The intermediate gear set K comprises a seventeenth gear 17 and a nineteenth gear 19 fixedly connected with the intermediate shaft m, an eighteenth gear 18 disposed between the seventeenth gear 17 and the nineteenth gear 19 and empty-sleeved on the intermediate shaft m, and a fifth synchronizer S5 disposed between the eighteenth gear 18 and the nineteenth gear 19. The eighteen-gauge gear 18 is in constant mesh with the thirty-gauge gear 30, and the nineteen-gauge gear 19 is in constant mesh with the thirty-two-gauge gear 32.

When the fifth synchronizer S5 is shifted to be connected with the eighteen-numbered gear 18, the eleventh synchronizer S11 is connected with the thirty-numbered gear 30 at the moment, and the power output shaft O outputs the rotating speed through the transmission ratio between the eighteen-numbered gear 18 and the thirty-numbered gear 30; when the fifth synchronizer S5 is shifted to be separated from the eighteen-th gear 18, the twelfth synchronizer S12 is connected with the thirty-two-th gear 32, and the power output shaft O outputs the rotating speed through the transmission ratio between the nineteen-th gear 19 and the thirty-two-th gear 32.

The first driven gear group N1 includes a twenty-first gear 20 and a twenty-first gear 21, which are idly mounted on the first driven shaft a1, and a sixth synchronizer S6 interposed between the twenty-first gear 21 and the twenty-first gear 20. The twenty-first gear 20 is in constant mesh with the seventeen-second gear 17, and the twenty-first gear 21 is in constant mesh with the eighteen-first gear 18.

When the sixth synchronizer S6 is shifted to be connected with the twentieth gear 20, the counter shaft m outputs the rotational speed through the gear ratio between the seventeen gear 17 and the twentieth gear 20; when the sixth synchronizer S6 is shifted to be connected with the twenty-first gear 21, the intermediate shaft m outputs the rotation speed through the transmission ratio between the eighteen-th gear 18 and the twenty-first gear 21.

The second driven gear group N2 includes a twenty-second gear 22 and a twenty-third gear 23 which are idly fitted on the second driven shaft a2, and a seventh synchronizer S7 interposed between the twenty-second gear 22 and the twenty-third gear 23. The twenty-two gear 22 is in constant mesh with the seventeen gear 17, and the twenty-three gear 23 is in constant mesh with the eighteen gear 18.

When the seventh synchronizer S7 is shifted to be connected with the twenty-second gear 22, the intermediate shaft m outputs the rotation speed through the transmission ratio between the seventeen-second gear 17 and the twenty-second gear 22; when the seventh synchronizer S7 is shifted to be connected with the twenty-third gear 23, the intermediate shaft m outputs the rotation speed through the gear ratio between the eighteen gear 18 and the twenty-third gear 23.

The third driven gear group N3 includes twenty-four gears 24 and twenty-five gears 25 which are idle-sleeved on the third driven shaft a3, and an eighth synchronizer S8 interposed between the twenty-four gears 24 and twenty-five gears 25. The twenty-four gears 24 are in constant mesh with the seventeen gears 17, and the twenty-five gears 25 are in constant mesh with the eighteen gears 18.

When the eighth synchronizer S8 is shifted to be connected with the twenty-four number gear 24, the intermediate shaft m outputs the rotation speed through the transmission ratio between the seventeen number gear 17 and the twenty-four number gear 24; when the eighth synchronizer S8 is shifted to connect with the twenty-fifth gear 25, the intermediate shaft m outputs the rotation speed through the transmission ratio between the eighteen gear 18 and the twenty-fifth gear 25.

The reverse driven gear set E is free of the twenty-sixth and twenty-

seventh gears

26 and 27 on the reverse driven shaft a4 and the ninth synchronizer S9 interposed between the twenty-sixth and twenty-

seventh gears

26 and 27. The twenty-sixth gear 26 is in constant mesh with the seventeen gear 17, and the twenty-seventh gear 27 is in constant mesh with the eighteen gear 18.

When the ninth synchronizer S9 is shifted to be connected with the twenty-sixth gear 26, the intermediate shaft m outputs the rotation speed through the transmission ratio between the twenty-sixth gear 26 and the seventeen gear 17; if the fifth synchronizer S5 is shifted to be separated from the eighteenth gear 18, the twelfth synchronizer S12 is connected with the thirty-two second gear 32, and the power output shaft O outputs the rotating speed through the transmission ratio between the nineteen second gear 19 and the thirty-two second gear 32.

When the ninth synchronizer S9 is shifted to be connected with the twenty-seventh gear 27, the middle shaft m outputs the rotating speed through the transmission ratio between the twenty-seventh gear 27 and the eighteen gear 18; if the fifth synchronizer S5 is shifted to be connected with the eighteenth gear 18, the eleventh synchronizer S11 can be selectively connected with the thirty-th gear 30, and the power output shaft O outputs the rotation speed through the transmission ratio between the eighteenth gear 18 and the thirty-th gear 30.

In a light load starting mode, the second clutch F2 is connected, the second synchronizer S2 is shifted to be connected with the tenth gear 10, the second driving shaft A2 outputs the rotation speed to the second driven shaft A2 with the transmission ratio between the fifth gear 5 and the tenth gear 10, the seventh synchronizer S7 is shifted to be connected with the twelfth gear 22, the intermediate shaft m outputs the rotation speed through the transmission ratio between the seventeen gear 17 and the twelfth gear 22, the fifth synchronizer S5 is shifted to be separated from the eighteenth gear 18, at this time, the twelfth synchronizer S12 is connected with the thirty-two gear 32, and the power output shaft O is started through the transmission ratio output rotation speed between the nineteen gear 19 and the thirty-two gear 32.

In the heavy load starting mode, while the power is transmitted in the light load starting mode, the third clutch F3 is connected, the third synchronizer S3 is shifted to be connected with the twelfth gear 12, the third driving shaft A3 outputs the rotating speed to the third driven shaft A3 with the transmission ratio between the sixth gear 6 and the twelfth gear 12, the eighth synchronizer S8 is shifted to be connected with the twenty-fourth gear 24, the rotating speed is output by the intermediate shaft m through the transmission ratio between the seventeen gear 17 and the twenty-fourth gear 24, so that the output torque of the intermediate shaft m is increased, and the nineteen gear 19 and the thirty-second gear 32 output the rotating speed to the power output shaft O with stronger torque to realize starting.

When the target rotation speed is reached, the third clutch F3 is gradually disengaged to be disconnected, and the second clutch F2 alone connects the second driving shaft A2 and the second driven shaft A2 to perform power transmission in the light-load starting mode.

Crawling and keeping off gear train unit U including arranging in on the power output shaft O and with thirty-one number gear 31, empty cover of thirty-two number gear 32 fixed connection are in twenty-eight number gear 28 on the power output shaft O, arranging in tenth synchronous ware S10 on the power output shaft O, arranging in on the crawl keep off the axle P and with crawl keep off No. thirty-three number gear 33 of axle P fixed connection and arrange in on the crawl keep off the axle P and with crawl keep off No. thirty-five number gear 35 of axle P fixed connection. The thirty-first gear 31 is in constant mesh with the thirty-fifth gear 35, and the twenty-eighth gear 28 is in constant mesh with the thirty-third gear 33.

When the crawling gear wheel set U works, the twelfth synchronizer S12 is separated from the thirty-two gear 32, and when the tenth synchronizer S10 is connected with the twenty-eight gear 28, the crawling gear shaft P outputs the rotating speed through the transmission ratio between the thirty-first gear 31 and the thirty-five gear 35, and then the power output shaft O outputs the rotating speed through the transmission ratio between the thirty-third gear 33 and the twenty-eight gear 28.

The four-wheel driving gear set H comprises a twenty-ninth gear 29 which is arranged on the power output shaft O and is fixedly connected with the power output shaft O, a thirty-sixth gear 36 which is fixedly connected with the four-wheel driving shaft G, and a thirty-fourth gear 34 which is arranged between the twenty-ninth gear 29 and the thirty-sixth gear 36 and is sleeved on the crawling gear shaft P in a hollow manner.

The twenty-ninth gear 29 is in constant mesh with the thirty-fourth gear 34, the thirty-fourth gear 34 is in constant mesh with the thirty-sixth gear 36, and the four-wheel drive shaft G outputs the rotation speed through the transmission ratio among the twenty-ninth gear 29, the thirty-fourth gear 34 and the thirty-sixth gear 36.

When the four-wheel drive clutch F4 is connected, the four-wheel drive shaft G transmits the rotational speed to the four-wheel drive driven shaft G, which in turn outputs four-wheel drive.

The "empty sleeve" mentioned in this embodiment refers to that the gear is sleeved on the shaft to realize the relative rotation on the shaft, and the empty sleeve may be that a bearing, a shaft sleeve or other parts are additionally arranged between the gear and the shaft, or the gear is directly arranged on the shaft. The bearing, the bushing are all devices known to the person skilled in the art and therefore not further described, neither described nor shown in the description.

It will be apparent to those skilled in the art that various modifications and variations can be made to the above-described exemplary embodiments of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

1. A gear shifting control method of a gearbox clutch, wherein the gearbox comprises a first clutch, a second clutch, a solenoid valve and a rotating speed sensor, and the gear shifting control method comprises the following steps:

executing gear shifting operation, wherein the first clutch is disengaged and simultaneously the second clutch is synchronously engaged;

the rotating speed sensor collects rotating speed values of the first clutch and the second clutch in the sliding friction process in real time, and a torque value is calculated through the rotating speed values;

the TCU receives a torque value calculated by the rotating speed value acquired by the rotating speed sensor and analyzes the torque value to obtain a corresponding gain coefficient, and the TCU adjusts the torque value of the clutch in the friction sliding process by taking the gain coefficient as a multiple;

in the process of disengaging the first clutch and combining the second clutch, the torque of the first clutch and the torque of the second clutch in the friction sliding process are adjusted through gain coefficients corresponding to the torque values of the first clutch and the second clutch in the friction sliding process, and stable gear shifting of power is achieved;

the disengaging process of the first clutch and the combining process of the second clutch are controlled by the hydraulic mechanism, and the electromagnetic valve adjusts the output current by taking the gain coefficient as a multiple so as to adjust the oil pressure of the hydraulic mechanism, thereby controlling the torque of the first clutch and the second clutch in the sliding friction process.

2. A method of controlling a transmission clutch shift as claimed in claim 1, characterized in that the method of transmission clutch shift control includes a heavy load start mode and a light load start mode during start:

3. A method of controlling a transmission clutch shift as claimed in claim 2, characterized by:

in the heavy-duty starting mode, an output speed of the third clutch when connecting the third driving shaft and the third driven shaft is greater than an output speed of the second clutch when connecting the second driving shaft and the second driven shaft.

4. A method of controlling shifting of a transmission clutch as claimed in claim 3, wherein said transmission comprises:

the power input shaft is connected with the engine and used for inputting engine power;

a PTO output shaft disposed coaxially with the power input shaft;

a power output shaft that outputs power after shifting;

the intermediate shaft is sleeved on the PTO output shaft in an empty way;

the intermediate gear set is arranged on the intermediate shaft;

the power output gear set is arranged on the power output shaft and is meshed with the middle gear set to carry out power output;

a first gear set;

a first drive shaft connected for power transfer with the power input shaft through the first gear set;

a first driven shaft disposed coaxially with the first driving shaft;

a first clutch interposed between the first driving shaft and a first driven shaft to connect or disconnect power transmission;

the first driven gear set is arranged on the first driven shaft and is connected with the intermediate gear set for power transmission;

a second gear set;

the second driving shaft is connected with the power input shaft through the second gear set to perform power transmission;

a second driven shaft disposed coaxially with the second driving shaft;

a second clutch interposed between the second driving shaft and a second driven shaft to connect or disconnect power transmission;

the second driven gear set is arranged on the second driven shaft and is connected with the intermediate gear set for power transmission;

a third gear set;

a third drive shaft connected with the power input shaft through the third gear set for power transmission;

a third driven shaft disposed coaxially with the third driving shaft;

a third clutch interposed between the third driving shaft and a third driven shaft to connect or disconnect power transmission;

the third driven gear set is arranged on the third driven shaft and is connected with the intermediate gear set for power transmission;

a reverse gear set;

the reverse gear driving shaft is connected with the power input shaft through the reverse gear set to perform power transmission;

the reverse gear driven shaft is coaxially arranged with the reverse gear driving shaft;

the reverse gear clutch is arranged between the reverse gear driving shaft and the reverse gear driven shaft and used for connecting or disconnecting power transmission;

the reverse gear intermediate shaft is arranged between the reverse gear driving shaft and the power input shaft;

the reverse gear driven gear set is arranged on the reverse gear driven shaft and is connected with the intermediate gear set for power transmission;

a creep gear group;

the crawling gear shaft is connected with the power output shaft through the crawling gear group to transmit power, and the crawling gear shaft and the power output shaft are arranged in parallel;

a four-wheel drive gear set;

the four-wheel driving shaft is connected with the power output shaft through the four-wheel driving gear set to transmit power, so that four-wheel driving power output is realized;

a four-wheel drive driven shaft, the four-wheel drive driven shaft being disposed coaxially with the four-wheel drive shaft;

and the four-wheel drive clutch is arranged between the four-wheel drive shaft and the four-wheel drive driven shaft and is used for connecting or disconnecting four-wheel drive power transmission.

5. The shift control method of a transmission clutch according to claim 4, characterized in that:

the first gear set comprises a first gear and a fourth gear which are arranged on the power input shaft, a seventh gear and an eighth gear which are arranged on the first driving shaft, and a first synchronizer which is arranged between the seventh gear and the eighth gear and arranged on the first driving shaft;

the first gear is in constant mesh with the seventh gear, and the fourth gear is in constant mesh with the eighth gear;

when the first synchronizer is connected with the seventh gear in a shifting mode, the first driving shaft outputs rotating speed to the first driven shaft in a transmission ratio between the first gear and the seventh gear;

6. The shift control method of a transmission clutch according to claim 5, characterized in that:

the second gear set comprises a second gear and a fifth gear which are arranged on the power input shaft, a ninth gear and a tenth gear which are arranged on the second driving shaft, and a second synchronizer which is arranged between the ninth gear and the tenth gear and is arranged on the second driving shaft;

the second gear is in constant mesh with the ninth gear, and the fifth gear is in constant mesh with the tenth gear;

when the second synchronizer is shifted to be connected with the ninth gear, the second driving shaft outputs the rotating speed to the second driven shaft at the transmission ratio between the second gear and the ninth gear;

when the second synchronizer is dialed to be connected with the No. ten gear, the second driving shaft outputs the rotating speed to the second driven shaft at the transmission ratio between the No. five gear and the No. ten gear;

in a light-load starting mode, the second synchronizer is shifted to be connected with the No. ten gear, and the second driving shaft outputs rotating speed to the second driven shaft according to the transmission ratio between the No. five gear and the No. ten gear.

7. The shift control method of a transmission clutch according to claim 6, characterized in that:

the third gear set comprises a third gear and a sixth gear which are arranged on the power input shaft, an eleventh gear and a twelfth gear which are arranged on the third driving shaft, and a third synchronizer which is arranged between the eleventh gear and the twelfth gear and is arranged on the third driving shaft;

the third gear is in constant mesh with the eleventh gear, and the sixth gear is in constant mesh with the twelfth gear;

when the third synchronizer is shifted to be connected with the eleventh gear, the third driving shaft outputs the rotating speed to the third driven shaft at the transmission ratio between the third gear and the eleventh gear;

when the third synchronizer is shifted to be connected with the No. twelve gear, the third driving shaft outputs the rotating speed to the third driven shaft at the transmission ratio between the No. six gear and the No. twelve gear;

in a heavy-load starting mode, the second synchronizer is shifted to be connected with the tenth gear, and the second driving shaft outputs rotating speed to the second driven shaft at a transmission ratio between the fifth gear and the tenth gear;

8. The shift control method of a transmission clutch according to claim 7, characterized in that:

the reverse gear set comprises a fifteen-gear and a sixteen-gear which are arranged on the reverse gear driving shaft, a thirteen-gear which is arranged on the reverse gear intermediate shaft and is arranged between the first-gear and the fifteenth-gear, a fourteen-gear which is arranged on the reverse gear intermediate shaft and is arranged between the fourth-gear and the sixteenth-gear, and a fourth synchronizer which is arranged between the fifteen-gear and the sixteen-gear and is arranged on the reverse gear driving shaft;

the thirteen-gear is in constant mesh with the first-gear and the fifteen-gear at the same time, and the fourteen-gear is in constant mesh with the fourth-gear and the sixteen-gear at the same time;

when the fourth synchronizer is shifted to be connected with the fifteenth gear, the reverse gear driving shaft outputs the rotating speed to the reverse gear driven shaft at the transmission ratio among the first gear, the thirteenth gear and the fifteenth gear;

when the fourth synchronizer is connected with the sixteenth gear in a shifting mode, the reverse driving shaft outputs rotating speed to the reverse driven shaft in a transmission ratio among the fourth gear, the fourteenth gear and the sixteenth gear;

the power output gear set comprises a thirty-grade gear which is sleeved on the power output shaft in an empty mode, a thirty-two-grade gear which is sleeved on the power output shaft in an empty mode, an eleventh synchronizer which is arranged on the left side of the thirty-grade gear and a twelfth synchronizer which is arranged on the right side of the thirty-two-grade gear;

when the eleventh synchronizer is connected with the thirty-second gear, the twelfth synchronizer is separated from the thirty-second gear, and the power output shaft outputs the rotating speed through the thirty-second gear;

9. The shift control method of a transmission clutch according to claim 8, characterized in that:

the intermediate gear set comprises a seventeen gear and a nineteen gear which are fixedly connected with the intermediate shaft, an eighteen gear which is arranged between the seventeen gear and the nineteen gear and is sleeved on the intermediate shaft in an empty way, and a fifth synchronizer which is arranged between the eighteen gear and the nineteen gear and is arranged on the intermediate shaft;

the eighteen gears are in constant meshing with the thirty gears, and the nineteen gears are in constant meshing with the thirty-two gears;

10. A method of controlling a transmission clutch shift as claimed in claim 9, characterized by:

the first driven gear set comprises a No. twenty gear and a No. twenty-first gear which are sleeved on the first driven shaft in an empty mode, and a sixth synchronizer which is arranged between the No. twenty gear and the No. twenty-first gear and arranged on the first driven shaft;

the twenty-first gear is normally meshed with the eighteen gear;

when the sixth synchronizer is shifted to be connected with the twenty-first gear, the intermediate shaft outputs the rotating speed through the transmission ratio between the eighteen gear and the twenty-first gear;

the second driven gear set comprises a twenty-two gear and a twenty-three gear which are sleeved on the second driven shaft in a hollow manner, and a seventh synchronizer which is arranged between the twenty-two gear and the twenty-three gear and arranged on the second driven shaft;

the twenty-two gear is in constant mesh with the seventeen gear, and the twenty-three gear is in constant mesh with the eighteen gear;

when the seventh synchronizer is shifted to be connected with the twenty-two gears, the intermediate shaft outputs the rotating speed through the transmission ratio between the seventeen gears and the twenty-two gears;

when the seventh synchronizer is shifted to be connected with the twenty-third gear, the intermediate shaft outputs the rotating speed through the transmission ratio between the eighteen gear and the twenty-third gear;

the third driven gear set comprises a twenty-four gear and a twenty-five gear which are sleeved on the third driven shaft in an empty mode, and an eighth synchronizer which is arranged between the twenty-four gear and the twenty-five gear and arranged on the third driven shaft;

the twenty-four gear is normally meshed with the seventeen gear, and the twenty-five gear is normally meshed with the eighteen gear;

when the eighth synchronizer is shifted to be connected with the twenty-four gears, the intermediate shaft outputs the rotating speed through the transmission ratio between the seventeen gears and the twenty-four gears;

when the eighth synchronizer is shifted to be connected with the twenty-fifth gear, the intermediate shaft outputs the rotating speed through the transmission ratio between the eighteen gear and the twenty-fifth gear;

in a light-load starting mode, a second clutch is connected, the second synchronizer is switched to be connected with the No. ten gear, the second driving shaft outputs rotating speed to the second driven shaft in a transmission ratio between a No. five gear and a No. ten gear, the seventh synchronizer is switched to be connected with the No. twenty-two gear, the intermediate shaft outputs rotating speed through the transmission ratio between a No. seventeen gear and a No. twenty-two gear, the fifth synchronizer is switched to be separated from the No. eighteen gear, the twelfth synchronizer is connected with the No. thirty-two gear at the moment, and the power output shaft is started through the transmission ratio output rotating speed between the No. nineteen gear and the No. thirty-two gear;

in a heavy-load starting mode, when power is transmitted in the light-load starting mode, a third clutch is connected, a third synchronizer is shifted to be connected with the twelfth gear, a third driving shaft outputs rotating speed to a third driven shaft according to the transmission ratio between the sixth gear and the twelfth gear, an eighth synchronizer is shifted to be connected with the twenty-four gear, the intermediate shaft outputs rotating speed through the transmission ratio between the seventeen gear and the twenty-four gear, the output torque of the intermediate shaft is further improved, and the nineteen gear and the thirty-two gear realize starting by outputting rotating speed to the power output shaft through stronger torque;

when the target rotating speed is reached, the third clutch is gradually disengaged to be disconnected, and the second clutch solely connects the second driving shaft and the second driven shaft to perform power transmission in the light-load starting mode.

11. The shift control method of a transmission clutch according to claim 10, characterized in that:

the crawling gear set comprises a thirty-first gear, a twenty-eighth gear, a tenth synchronizer, a thirty-third gear and a thirty-fifth gear, the thirty-first gear is arranged on the power output shaft and fixedly connected with the thirty-second gear, the twenty-eighth gear is sleeved on the power output shaft in a hollow mode, the tenth synchronizer is arranged on the power output shaft, the thirty-third gear is arranged on the crawling gear shaft and fixedly connected with the crawling gear shaft, and the thirty-fifth gear is arranged on the crawling gear shaft and fixedly connected with the crawling gear shaft;

the thirty-first gear is in constant mesh with a thirty-fifth gear, and the twenty-eighth gear is in constant mesh with the thirty-third gear;

when the crawling gear set works, the twelfth synchronizer is separated from the thirty-two gears, and when the tenth synchronizer is connected with the twenty-eight gears, the crawling gear shaft outputs the rotating speed through the transmission ratio between the thirty-first gear and the thirty-five gears, and then the power output shaft outputs the rotating speed through the transmission ratio between the thirty-third gear and the twenty-eight gears;

the four-wheel driving gear set comprises a twenty-nine gear which is arranged on the power output shaft and is fixedly connected with the power output shaft, a thirty-six gear which is fixedly connected with the four-wheel driving shaft, and a thirty-four gear which is arranged between the twenty-nine gear and the thirty-six gear and is sleeved on the crawling gear shaft in a hollow manner;

the twenty-ninth gear is in constant mesh with the thirty-fourth gear, the thirty-fourth gear is in constant mesh with the thirty-sixth gear, and the four-wheel driving shaft outputs the rotating speed through the transmission ratio among the twenty-ninth gear, the thirty-fourth gear and the thirty-sixth gear;

when the four-wheel drive clutch is connected, the four-wheel drive shaft transmits the rotational speed to the four-wheel drive driven shaft, which in turn outputs four-wheel drive.

12. A gearbox comprising a gearbox clutch shift control method according to any one of claims 1 to 11.