Tractor combined mechanical transmission automatic gear shifting device, system and tractor

Abstract

The present application relates to tractor combined mechanical transmission automatic gear shifting device, system and tractor, the device includes main box gear shifting execution mechanism, auxiliary box gear shifting execution mechanism, transmission, the main box gear shifting execution mechanism and auxiliary box gear shifting execution mechanism are installed on the transmission respectively, the main box gear shifting execution mechanism and auxiliary box gear shifting execution mechanism are connected with drive block and drive the drive block moves respectively, the drive block is matched with the drive groove in the transmission and carries out gear shifting.This application is mainly for the development of mechanical transmission electric control electric gear shifting control, mainly by several brushless DC motor drive realizes transmission gear shifting action, can realize gear shifting automation.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of agricultural machinery, and particularly relates to a tractor combined mechanical gearbox automatic gear shifting device, system and tractor. BACKGROUND

[0002] At present, the mechanical gear shifting is adopted in the agricultural tractor mechanical gearbox which is widely used in the market. The existing tractor traditional manual mechanical gear shifting scheme is as follows: after the engine of the vehicle is started, the driver first steps on the clutch, then selects the main gearbox and the auxiliary gearbox starting gear position, then slowly releases the clutch to start the vehicle, and after the vehicle is started, the driver needs to continuously step on the accelerator, and the vehicle moves forward. When the vehicle speed reaches a certain degree, the driver steps on the clutch again, and the main gearbox gear position is increased by one. If the main gearbox is changed to the highest gear, the main gearbox needs to be hung in the neutral gear first, then the auxiliary gearbox is increased, and then the main gearbox is hung in the lowest gear position. Since the tractor gearbox has many gears, the fatigue strength of the driver is greatly increased. SUMMARY

[0003] The present application relates to the field of agricultural machinery, and particularly relates to a tractor combined mechanical gearbox automatic gear shifting device, system and tractor.

[0004] The technical scheme for solving the above technical problem is as follows: a tractor combined mechanical gearbox automatic gear shifting device, comprising a main gearbox gear shifting execution mechanism, an auxiliary gearbox gear shifting execution mechanism and a gearbox, the main gearbox gear shifting execution mechanism and the auxiliary gearbox gear shifting execution mechanism are respectively installed on the gearbox, driving blocks are respectively connected to the main gearbox gear shifting execution mechanism and the auxiliary gearbox gear shifting execution mechanism, and the driving blocks are driven to move, the driving blocks are matched with driving grooves in the gearbox to perform gear shifting.

[0005] The present application relates to the field of agricultural machinery, and particularly relates to a tractor combined mechanical gearbox automatic gear shifting device, system and tractor.

[0006] On the basis of the above technical scheme, the present application can be further improved as follows.

[0007] Further, the gear shifting execution mechanisms of the main gearbox gear shifting execution mechanism and the auxiliary gearbox gear shifting execution mechanism respectively comprise a gear shifting motor, a gear shifting gear, a gear shifting worm and a gear shifting shaft, the driving end of the gear shifting motor is connected with the gear shifting worm, the gear shifting worm is engaged with the gear shifting gear and drives the gear shifting gear to rotate, the gear shifting shaft is fixedly connected with the gear shifting gear and rotates with the gear shifting gear, one end of the gear shifting shaft is movably connected with the driving block and drives the driving block to move, and the driving block is matched with the driving groove in the gearbox to perform gear shifting.

[0008] The beneficial effects of adopting the above-mentioned further solutions are: the use of electric gear selection design eliminates the original gear selection structure on the gearbox, the gear selection is accurate, less prone to jamming, and has high efficiency, high precision, and good reliability. It also eliminates the need for manual operation and greatly reduces the manufacturing cost of the gearbox.

[0009] Furthermore, one end of the gear selection shaft is a ball joint structure, and the drive lever is provided with a drive groove. The ball joint structure is movably disposed in the drive groove and is in clearance fit with the inner sidewall of the drive groove.

[0010] The gear selection position sensor is installed at the other end of the gear selection shaft; the two ends of the gear selection shaft are supported and connected by bearings; the gear selection gear is a sector gear; the gear selection gear is sleeved on the gear selection shaft and connected to the gear selection shaft by a second pin, which is welded and fixed to the gear selection shaft.

[0011] The beneficial effects of adopting the above-mentioned further solution are as follows: The ball joint structure at one end of the gear selection shaft is movably set in the drive groove. During gear selection, the ball joint structure drives the drive groove, causing the drive lever to move linearly. The gear selection angle and position are accurately determined by the gear selection position sensor, thus smoothly achieving precise gear selection. The design of the drive lever and drive groove greatly improves the gear selection positioning, optimizes the entire actuator, improves control accuracy, significantly reduces costs, solves the problem of incomplete or excessive gear selection, and enhances the reliability of the gear selection mechanism. The gear selection shaft is supported and mounted on the housing by two bearings, optimizing the fixation of the gear selection shaft while ensuring higher coaxiality, effectively overcoming axial forces during operation, and improving the service life of the mechanism. First, the gear selection gear is positioned on the gear selection shaft using a pin, and then the gear selection gear is welded and fixed to the pin, making the connection between the gear selection gear and the gear selection shaft more stable and firm.

[0012] Furthermore, the shifting actuators of the main gearbox shifting mechanism and the auxiliary gearbox shifting mechanism respectively include a shifting motor, a shifting gear, a shifting worm, and a shifting shaft. The drive end of the shifting motor is connected to the shifting worm, the shifting worm meshes with the shifting gear and drives the shifting gear to rotate, the shifting shaft is fixedly connected to the shifting gear and rotates with the shifting gear, and a drive paddle is axially movable on the shifting shaft. The drive paddle cooperates with the drive slot in the gearbox to perform gear selection and shifting.

[0013] The beneficial effects of adopting the above-mentioned further solution are: the original gearbox shifting structure is eliminated and replaced with an electric shifting actuator, which solves the technical defects of the existing shifting mechanism, such as heavy shifting work, difficulty in shifting, and inaccurate shifting position, and greatly reduces the manufacturing cost of the gearbox.

[0014] Furthermore, the shift shaft is provided with a spline, and the drive lever is axially movable on the shift shaft via the spline; the shift position sensor is installed at one end of the shift shaft; the shift gear is a sector gear; the two ends of the shift shaft are supported and connected by bearings; the shift gear is sleeved on the shift shaft and connected to the shift shaft by a first pin, which is welded and fixed to the shift shaft.

[0015] The advantages of adopting the above-mentioned further solution are: The shift shaft is equipped with an involute spline structure, allowing the drive lever to be axially movable and mounted on the shift shaft, facilitating control by the shifting and selection mechanisms. Bearings support both ends of the shift shaft, making the connection more stable and reliable. First, a pin is used to position the shift gear onto the shift shaft, and then the shift gear is welded and fixed to the pin, making the connection between the shift gear and the shift shaft more stable and secure.

[0016] Furthermore, it also includes a shuttle gear solenoid valve, which is connected to the wet clutch inside the gearbox.

[0017] An automatic shifting system for a tractor-mounted mechanical gearbox includes a controller and a main gearbox shifting actuator, a secondary gearbox shifting actuator, a gearbox, and a shift signal triggering unit, all of which are communicatively connected to the controller. The main gearbox shifting actuator and the secondary gearbox shifting actuator are each equipped with a shifting position sensor. The shifting position sensor is connected to the controller and sends the collected shifting position signal to the controller. The controller receives and controls the operation of the shifting actuator based on the trigger signal received by the shift signal triggering unit and the shifting position signal.

[0018] The beneficial effects of this invention are as follows: Addressing the cumbersome shifting operations and high workload associated with existing manual combined mechanical gearboxes on tractors, the driver provides shifting commands via signals such as the electronic shift lever and brake input. The controller receives and processes these signals, issuing different commands based on varying driving intentions. By controlling the main gearbox shifting mechanism, the auxiliary gearbox shifting mechanism, and the wet clutch, the controller enables one-button shifting of the combined mechanical gearbox, significantly reducing the operator's workload and improving work efficiency.

[0019] Furthermore, it also includes a throttle opening sensor and a speed sensor respectively connected to the controller. The throttle opening sensor is used to collect the throttle opening and send it to the controller, and the speed sensor is used to collect the engine speed and send it to the controller.

[0020] Furthermore, it also includes a throttle opening sensor, an engine speed sensor, and an orthogonal speed sensor for detecting the state of the wet clutch, all connected to the controller respectively; the throttle opening sensor is used to collect the throttle opening and send it to the controller, and the speed sensor is used to collect the engine speed and send it to the controller.

[0021] The controller is used to control the main gearbox shifting mechanism and the auxiliary gearbox shifting mechanism to upshift when the throttle opening increases and the engine speed exceeds the speed threshold corresponding to the current gear; and to control the main gearbox shifting mechanism and the auxiliary gearbox shifting mechanism to downshift when the throttle opening decreases and the engine speed is lower than the speed threshold corresponding to the current gear. Automatic upshifting and downshifting control can be achieved by using a throttle opening sensor and a speed sensor in conjunction. A quadrature speed sensor can be used to determine whether the wet clutch is fully disengaged, thus achieving automated clutch control.

[0022] Furthermore, the shift signal triggering unit includes one or more of the following: shift lever, electronic touch screen, shift button, clutch pedal, brake, accelerator, and FNR lever.

[0023] The beneficial effect of adopting the above-mentioned further solution is that the controller can perform shifting and clutch control according to different shifting signal triggers.

[0024] A tractor comprising the aforementioned tractor-mounted mechanical gearbox automatic shifting device or system.

[0025] The tractor of the present invention can achieve one-button shifting of the combined mechanical gearbox by controlling the main gearbox shifting actuator, the auxiliary gearbox shifting actuator, and the wet clutch, which greatly reduces the labor intensity of the operator and improves the work efficiency. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the gear selection actuator of the present invention. Figure 1 ;

[0027] Figure 2 This is a schematic diagram of the gear selection actuator of the present invention. Figure 2 ;

[0028] Figure 3 This is a schematic diagram of the shift actuator of the present invention. Figure 1 ;

[0029] Figure 4 This is a schematic diagram of the shift actuator of the present invention. Figure 2 ;

[0030] Figure 5 This is a cross-sectional view of the gear shifting actuator of the present invention;

[0031] Figure 6 This is a schematic diagram of the overall structure of the automatic gear shifting device of the present invention;

[0032] Figure 7 This is a schematic diagram of the automatic gear shifting system of the present invention.

[0033] The attached diagram lists the components represented by each number as follows:

[0034] 100. Gear selector motor; 101. Gear selector gear; 102. Gear selector worm gear; 103. Gear selector shaft; 104. Gear selector position sensor; 105. Ball joint structure; 106. Bearing; 107. Second pin;

[0035] 200. Shift motor; 201. Shift gear; 202. Shift worm; 203. Shift shaft; 204. Shift position sensor; 205. Spline; 206. First pin; 207. Weld joint;

[0036] 300, drive lever; 301, drive slot.

[0037] 400. Gearbox; 401. Wet clutch; 500. Main gearbox shifting actuator; 600. Auxiliary gearbox shifting actuator; 700. Shuttle gear solenoid valve. Detailed Implementation

[0038] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0039] Example 1

[0040] like Figures 1-6 As shown, the automatic shifting device of the tractor combined mechanical gearbox in this embodiment includes a main gearbox shifting actuator, a secondary gearbox shifting actuator, and a gearbox 400. The main gearbox shifting actuator and the secondary gearbox shifting actuator are respectively mounted on the gearbox 400. Drive blocks 300 are respectively connected to the main gearbox shifting actuator and the secondary gearbox shifting actuator, and drive the drive blocks 300 to move. The drive blocks 300 cooperate with the drive groove in the gearbox 400 to perform gear shifting.

[0041] This embodiment mainly focuses on the development of an electronically controlled gear shifting system for mechanical gearboxes. It is mainly driven by several DC brushed motors to realize the gear shifting action and can achieve automated gear selection and shifting.

[0042] Example 2

[0043] like Figures 1-6As shown, the automatic shifting device of the tractor combined mechanical gearbox in this embodiment includes a main gearbox shifting actuator, a secondary gearbox shifting actuator, and a gearbox 400. The main gearbox shifting actuator and the secondary gearbox shifting actuator are respectively mounted on the gearbox 400. Drive blocks 300 are respectively connected to the main gearbox shifting actuator and the secondary gearbox shifting actuator, and drive the drive blocks 300 to move. The drive blocks 300 cooperate with the drive groove in the gearbox 400 to perform gear shifting.

[0044] like Figure 1 , Figure 2 and Figure 5 As shown, the gear selection actuator in the main gearbox shifting actuator and the auxiliary gearbox shifting actuator includes a gear selection motor 100, a gear selection gear 101, a gear selection worm 102, and a gear selection shaft 103. The drive end of the gear selection motor 100 is connected to the gear selection worm 102. The gear selection worm 102 meshes with the gear selection gear 101 and drives the gear selection gear 101 to rotate. The gear selection shaft 103 is fixedly connected to the gear selection gear 101 and rotates with the gear selection gear 101. One end of the gear selection shaft 103 is movably connected to a drive lever 300 and drives the drive lever 300 to move. The drive lever 300 cooperates with the drive groove in the gearbox 400 to perform gear selection and shifting. A gear selection position sensor 104 is installed on the gear selection shaft 103.

[0045] like Figure 2 As shown, in this embodiment, one end of the gear selection shaft 103 is a ball joint structure 105, and the drive lever 300 is provided with a drive groove 301. The ball joint structure 105 is movably disposed within the drive groove 301. The ball joint structure 105 at one end of the gear selection shaft 103 optimizes gear selection accuracy, enabling precise and reliable gear selection and avoiding the problems of simultaneously engaging two gears or failing to drive the shift. The drive groove 301 on the drive lever 300 allows for precise and efficient gear selection. The ball joint structure 105 at one end of the gear selection shaft 103 is movably disposed within the drive groove 301. During gear selection, the ball joint structure 105 drives the drive groove 301, causing the drive lever 300 to move linearly. The gear selection angle and position are accurately determined by the gear selection position sensor, thus achieving precise gear selection. The design of the drive lever and drive slot has greatly improved the gear selection and shifting positioning, optimized the entire actuator, improved control accuracy, significantly reduced costs, solved the problem of incomplete or excessive gear selection, and enhanced the reliability of the gear selection and shifting mechanism.

[0046] In this embodiment, the ball head structure 105 is clearance-fitted with the inner sidewall of the drive groove 301.

[0047] like Figure 1 and Figure 2As shown, in this embodiment, the gear selection position sensor 104 is installed at the other end of the gear selection shaft 103; both ends of the gear selection shaft 103 are supported and connected by bearings 106, which can be ball bearings. The gear selection shaft is supported and installed on the housing by two ball bearings, which optimizes the fixation of the gear selection shaft, ensures higher coaxiality, effectively overcomes axial force during operation, and improves the service life of the mechanism.

[0048] The gear selection gear 101 in this embodiment is a sector gear, specifically a sector helical gear. By driving the sector gear to rotate, the gear selection shaft connected to the sector gear rotates, which in turn drives the ball joint structure on the gear selection shaft to rotate and drive the shift block to move.

[0049] like Figure 1 , Figure 2 and Figure 5 As shown, the gear selector 101 is sleeved on the gear selector shaft 103 and connected to the gear selector shaft 103 by a second pin 107. The gear selector 101 is welded to the gear selector shaft 103, and the second pin 107 is welded and fixed to the gear selector shaft 103. The weld joint 207 is as follows. Figure 5 As shown, the gear selector is first positioned onto the gear selector shaft using a pin, and then the gear selector is welded and fixed to the pin, making the connection between the gear selector and the gear selector shaft more stable and secure.

[0050] The working principle of the gear selection actuator of the gearbox in this embodiment is as follows: when selecting a gear, the gear selection motor 100 drives the gear selection worm gear 102 to rotate, the gear selection worm gear 102 drives the gear selection gear 101, the gear selection gear 101 drives the gear selection shaft 103 to rotate, and the gear selection shaft 103 in turn drives the drive block 300 fixedly connected to it to rotate, and the drive block 300 completes the gear selection action; the gear selection position sensor 104 is connected to the gear selection shaft 103 to detect its rotation angle, and the gear selection shaft 103 and the gear selection gear 101 are integrally connected. The gear selection shaft 103 is mounted on the housing structure via two ball bearings. The ball head structure 105 on the gear selection shaft 103 is fitted with a clearance within the drive groove 301 of the drive block 300. During gear selection, the ball head structure 105 on the gear selection shaft 103 drives the drive groove, causing the drive block 300 to move linearly. The gear selection angle and position are accurately determined by the gear selection position sensor 104, thus achieving accurate gear selection. The presence of the drive block 300 and its drive groove 301, along with the setting of the gear selection position sensor, has greatly improved the gear selection positioning technology, optimized the entire actuator structure, improved control accuracy, significantly reduced costs, solved the problem of incomplete or excessive gear selection, and enhanced the reliability of the gear selection mechanism.

[0051] In this embodiment, the gear selection mechanism features an integrated gear selection shaft, enabling rapid and precise control of the gear selection position. This improves component strength and transmission accuracy, preventing the simultaneous selection of two gears. The gear selection shaft is seamlessly connected to the housing using two ball bearings, significantly enhancing the accuracy and reliability of the components. The ball joint of the gear selection shaft is designed in a spherical shape to reduce stress concentration and prevent jamming, thereby improving the positioning accuracy and stability of the entire system. The ball joint directly drives the drive slot of the drive lever during gear selection, reducing selection time and significantly improving transmission efficiency. This embodiment reduces the number of parts related to the gear selection position, optimizes the installation method, simplifies the overall actuator structure, improves gear selection accuracy, reduces the processing cost of related parts, and offers good economic performance.

[0052] This invention is mainly aimed at the development of an electronically controlled gear shifting system for mechanical gearboxes. It is mainly driven by several DC brushed motors to realize the gear shifting action and can achieve automated gear selection and shifting.

[0053] Example 3

[0054] In addition to the contents of Embodiment 1 or Embodiment 2, the automatic gear shifting system for harvesting machinery in this embodiment includes the following: Figures 3-5 As shown, the shifting actuators in the main gearbox shifting actuator and the auxiliary gearbox shifting actuator include a shifting motor 200, a shifting gear 201, a shifting worm gear 202, a shifting shaft 203, and a shifting position sensor 204. The drive end of the shifting motor 200 is connected to the shifting worm gear 202. The shifting worm gear 202 meshes with the shifting gear 201 and drives the shifting gear 201 to rotate. The shifting shaft 203 is fixedly connected to the shifting gear 201 and rotates with the shifting gear 201. A drive lever 300 is axially movable on the shifting shaft 203. The drive lever 300 cooperates with the drive groove in the gearbox 400 to select and shift gears. The shifting shaft 203 is provided with a shifting position sensor 104.

[0055] like Figure 2 As shown, in this embodiment, the shift shaft 203 is provided with a spline 205, and the drive lever 300 is axially movable on the shift shaft 203 via the spline 205. The drive lever 300 is sleeved on the shift shaft 203. The shift shaft is provided with an involute spline structure, which allows the drive lever to be axially movable on the shift shaft, facilitating control of it by the shift mechanism and the gear selection mechanism.

[0056] like Figure 2 As shown, in this embodiment, the shift position sensor 204 is installed at one end of the shift shaft 203. This facilitates the detection of the shift shaft's position information.

[0057] likeFigure 1 As shown, the shift gear 201 in this embodiment is a sector gear. By driving the sector gear to rotate, the shift shaft connected to the sector gear rotates, which in turn drives the drive paddle on the shift shaft to rotate and perform gear shifting.

[0058] like Figure 1 and Figure 2 As shown, in this embodiment, the shift shaft 203 is supported and connected at both ends by bearings; specifically, one end of the shift shaft 203 is supported and connected by a needle roller bearing, and the other end is supported and connected by a ball bearing. The use of bearings at both ends of the shift shaft makes the connection more stable and reliable.

[0059] like Figure 1 , Figure 2 and Figure 5 As shown, in this embodiment, the shift gear 201 is sleeved on the shift shaft 203 and connected to the shift shaft 203 by a first pin 206. The shift gear 201 and the shift shaft 203 are welded and fixed, and the first pin 206 is also welded and fixed to the shift shaft 203. First, the shift gear is positioned on the shift shaft using a pin, and then the shift gear is welded and fixed to the pin, making the connection between the shift gear and the shift shaft more stable and secure.

[0060] The working principle of the gear shifting actuator of the gearbox in this embodiment is as follows: the shifting motor 200 drives the shifting worm 202 to rotate. The shifting worm 202 is supported and connected to the housing by the bearing 106. The shifting worm 202 drives the shifting gear 201 that meshes with it to rotate. The shifting gear 201 is connected to the shifting shaft 203 and drives the shifting shaft 203 to rotate. The shifting shaft 203 is supported and connected to the housing by the bearing 106. The shifting position sensor 204 is connected to the shifting shaft 203 to monitor the rotation angle. The drive block 300 is connected to the shifting shaft 203 through the spline 205 and rotates under the drive of the shifting shaft 203 to perform the shifting action.

[0061] The shift motor 200 is fixed to the housing and is rigidly connected to the shift worm gear 202. The shift motor 200 rotates forward and backward to shift between different gears within the same shift level. The shift shaft 203 is connected to the shift gear 201 via a pin and welding method, and the shift shaft 203 is connected to the drive lever 300 via a spline 205. Due to the large axial force generated during shifting, a double ball bearing support method is used to reduce the product's structural size. The rotation of the shift worm gear 202 drives the rotation of the shift shaft 203, ultimately achieving the shifting function. The shift position sensor 204 is connected to the shift shaft 203 to monitor the shift position in real time. Once the correct shift position is reached, the shift motor 200 stops working, and the shift position sensor 204 provides real-time feedback on the gear position. If a change in the gear position is detected, the motor generates a reverse self-locking force to prevent disengagement.

[0062] This embodiment features high precision control throughout the shifting process, with real-time monitoring of the shift position. After gear engagement, a shift position sensor provides real-time feedback, ensuring the transmission does not disengage, resulting in high reliability and transmission efficiency. The shifting mechanism in this embodiment has a simple structure, low cost, good economic performance, promising prospects for widespread application, and high practicality.

[0063] This invention is mainly aimed at the development of an electronically controlled gear shifting system for mechanical gearboxes. It is mainly driven by several DC brushed motors to realize the gear shifting action and can achieve automated gear selection and shifting.

[0064] Example 4

[0065] In addition to the contents of Embodiment 1, Embodiment 2, or Embodiment 3, the automatic gear shifting device for harvesting machinery in this embodiment also includes the following: Figure 6 As shown, it also includes a shuttle gear solenoid valve 700, which is connected to the wet clutch 401 inside the gearbox 400 to control the engagement or disengagement of the wet clutch 401.

[0066] Example 5

[0067] like Figures 1-7 As shown, this embodiment of an automatic shifting system for a tractor-mounted mechanical gearbox includes any of the devices described in Embodiments 1-4, and further includes a controller, which may be a TCU. The main gearbox shifting actuator 500, the auxiliary gearbox shifting actuator 600, the gearbox 400, and the shift signal triggering unit are all communicatively connected to the controller. The main gearbox shifting actuator 500 and the auxiliary gearbox shifting actuator 600 are each equipped with a shifting position sensor, the installation position of which can be found in Embodiments 1-3. The shifting position sensor is connected to the controller and sends the collected shifting position signal to the controller. The controller receives and controls the shuttle gear solenoid valve 700 to disconnect or engage with the wet clutch 401 within the gearbox and the shifting actuator based on the trigger signal received by the shift signal triggering unit and the shifting position signal.

[0068] This embodiment addresses the cumbersome shifting operations and high workload associated with existing manual combined mechanical transmissions on tractors. The driver provides shifting commands via an electronic shift lever and brake input. The controller receives and processes these signals, issuing different commands based on varying driving intentions. By controlling the main gearbox shifting mechanism, the auxiliary gearbox shifting mechanism, and the wet clutch, the controller enables one-button shifting of the combined mechanical transmission, significantly reducing operator workload and improving operational efficiency.

[0069] This embodiment primarily focuses on the development of an electronically controlled gear shifting system for a 12-speed mechanical gearbox. It utilizes four DC brushed motors to drive the gearbox shifting action. This embodiment is mainly applied to the control of a novel gear shifting actuator in agricultural machinery gearboxes, achieving closed-loop position control for gear shifting primarily through motor PWM control. This embodiment can automatically adjust the motor's duty cycle in real time based on changes in the position sensor. The TCU controller has a protection function for the drive motor, preventing prolonged high duty cycle blocking, extending the drive motor's lifespan, and enabling normal operation even in harsh environments, meeting the environmental requirements of agricultural machinery.

[0070] Example 6

[0071] like Figures 1-7 As shown, this embodiment of an automatic shifting system for a tractor-mounted mechanical gearbox includes any of the devices described in Embodiments 1-4, and further includes a controller, which may be a TCU. The main gearbox shifting actuator 500, the auxiliary gearbox shifting actuator 600, the shuttle gear solenoid valve 700, the gearbox 400, and the shift signal triggering unit are all communicatively connected to the controller. The main gearbox shifting actuator 500 and the auxiliary gearbox shifting actuator 600 are each equipped with a shifting position sensor, the installation position of which can be found in Embodiments 1-3. The shifting position sensor is connected to the controller and sends the collected shifting position signal to the controller. The controller receives and controls the shuttle gear solenoid valve 700 to disengage or engage with the wet clutch 401 within the gearbox 400 and the shifting actuator based on the trigger signal received by the shift signal triggering unit and the shifting position signal.

[0072] The automatic shifting system of a tractor combined mechanical gearbox in this embodiment also includes a throttle opening sensor and a speed sensor respectively connected to the controller. The throttle opening sensor is used to collect the throttle opening and send it to the controller, and the speed sensor is used to collect the engine speed and send it to the controller.

[0073] The controller is used to control the main gearbox shift actuator 500 and the auxiliary gearbox shift actuator 600 to upshift when the throttle opening increases and the engine speed exceeds the speed threshold corresponding to the current gear; and to control the main gearbox shift actuator 500 and the auxiliary gearbox shift actuator 600 to downshift when the throttle opening decreases and the engine speed is lower than the speed threshold corresponding to the current gear. Automatic upshifting and downshifting control can be achieved by using a throttle opening sensor and a speed sensor in conjunction.

[0074] The gearbox 400 also includes an orthogonal speed sensor for detecting the state of the wet clutch 401. The orthogonal speed sensor can be used to determine whether the wet clutch is fully disengaged, thus achieving automated clutch engagement control.

[0075] Specifically, the shift signal triggering unit includes one or more of the following: shift lever, electronic touch screen, shift button, clutch pedal, brake, accelerator, and FNR lever. The controller can perform shifting and clutch control according to different shift signal triggering units.

[0076] This embodiment addresses the cumbersome shifting operations and high workload associated with existing manual combined mechanical transmissions on tractors. The driver provides shifting commands via an electronic shift lever and brake input. The controller receives and processes these signals, issuing different commands based on varying driving intentions. By controlling the main gearbox shifting mechanism, the auxiliary gearbox shifting mechanism, and the wet clutch, the controller enables one-button shifting of the combined mechanical transmission, significantly reducing operator workload and improving work efficiency.

[0077] This embodiment primarily focuses on the development of an electronically controlled gear shifting system for a 12-speed mechanical gearbox. It utilizes four DC brushed motors to drive the gearbox shifting action. This embodiment is mainly applied to the control of a novel gear shifting actuator in agricultural machinery gearboxes, achieving closed-loop position control for gear shifting primarily through motor PWM control. This embodiment can automatically adjust the motor's duty cycle in real time based on changes in the position sensor. The TCU controller has a protection function for the drive motor, preventing prolonged high duty cycle blocking, extending the drive motor's lifespan, and enabling normal operation even in harsh environments, meeting the environmental requirements of agricultural machinery.

[0078] Example 7

[0079] This embodiment of a tractor includes any of the automatic shifting devices of the combined mechanical gearbox in embodiments 1-4, or the system of embodiment 5, or the system of embodiment 6. The tractor of this embodiment can achieve one-button shifting of the combined mechanical gearbox by controlling the main gearbox shifting actuator, the auxiliary gearbox shifting actuator, and the wet clutch, significantly reducing the operator's workload and improving work efficiency.

[0080] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0081] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0082] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0083] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0084] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0085] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An automatic shifting system for a tractor-mounted combined mechanical gearbox, characterized in that, Electric shift control for a 12-speed mechanical transmission; including a controller and a main gearbox shifting actuator, a secondary gearbox shifting actuator, a transmission, a shift signal trigger, a throttle opening sensor, a shuttle gear solenoid valve, a speed sensor, and an orthogonal speed sensor for detecting the state of a wet clutch, all of which are respectively connected to the controller in communication. The main gear shifting mechanism and the auxiliary gear shifting mechanism are respectively installed on the gearbox. Drive blocks are connected to the main gear shifting mechanism and the auxiliary gear shifting mechanism respectively. A plurality of DC brushed motors in the main gear shifting mechanism and the auxiliary gear shifting mechanism drive the drive blocks to move. The drive blocks cooperate with the drive slots in the gearbox to perform gear shifting. The main gearbox shifting actuator and the auxiliary gearbox shifting actuator are respectively equipped with shifting position sensors. The shifting position sensors are connected to the controller and send the collected shifting position signals to the controller. The controller is used to receive and control the operation of the shifting actuator according to the trigger signal received by the shifting signal triggering unit and the shifting position signals. The throttle opening sensor is used to collect the throttle opening and send it to the controller; the speed sensor is used to collect the engine speed and send it to the controller. The controller is used to control the main gearbox shifting mechanism and the auxiliary gearbox shifting mechanism to upshift when the throttle opening increases and the engine speed exceeds the speed threshold corresponding to the current gear; and to control the main gearbox shifting mechanism and the auxiliary gearbox shifting mechanism to downshift when the throttle opening decreases and the engine speed is lower than the speed threshold corresponding to the current gear. The gear selection actuators of the main gearbox and the auxiliary gearbox each include a gear selection motor, a gear selection gear, a gear selection worm, and a gear selection shaft. The drive end of the gear selection motor is connected to the gear selection worm. The gear selection worm meshes with the gear selection gear and drives the gear selection gear to rotate. The gear selection shaft is fixedly connected to the gear selection gear and rotates with the gear selection gear. One end of the gear selection shaft is movably connected to a drive shift block and drives the drive shift block to move. The drive shift block cooperates with the drive slot in the gearbox to perform gear selection and shifting. The shifting actuators of the main gearbox shifting mechanism and the auxiliary gearbox shifting mechanism each include a shifting motor, a shifting gear, a shifting worm, and a shifting shaft. The drive end of the shifting motor is connected to the shifting worm. The shifting worm meshes with the shifting gear and drives the shifting gear to rotate. The shifting shaft is fixedly connected to the shifting gear and rotates with the shifting gear. A drive paddle is axially movable on the shifting shaft. The drive paddle cooperates with the drive slot in the gearbox to perform gear selection and shifting. The shuttle-type solenoid valve is connected to the wet clutch inside the gearbox. The shift signal triggering unit includes one or more of the following: shift lever, electronic touch screen, shift button, clutch pedal, brake, accelerator, and FNR lever; One end of the gear selection shaft is a ball head structure, and the drive block is provided with a drive groove. The ball head structure is movably disposed in the drive groove and is in clearance fit with the inner sidewall of the drive groove. A gear selection position sensor is installed at the other end of the gear selection shaft; both ends of the gear selection shaft are supported and connected by bearings; the gear selection gear is a sector gear; the gear selection gear is sleeved on the gear selection shaft and connected to the gear selection shaft by a second pin, which is welded and fixed to the gear selection shaft; The shift shaft is provided with a spline, and the drive lever is axially movable on the shift shaft via the spline; the shift position sensor is installed at one end of the shift shaft; the shift gear is a sector gear; the two ends of the shift shaft are supported and connected by bearings; the shift gear is sleeved on the shift shaft and connected to the shift shaft by a first pin, which is welded and fixed to the shift shaft.

2. A tractor, characterized in that, The automatic shifting system for a tractor-mounted mechanical gearbox as described in claim 1.

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