PTO gearbox and tractor

Abstract

The utility model relates to a PTO gearbox and a tractor. The PTO gearbox comprises a box body, and a main shaft, a gear shifting shaft, an auxiliary speed changing shaft and an output shaft which are parallel to one another are rotationally installed on the box body; a reverse gear, a slow gear, a fast gear and a main shaft gear are mounted on the main shaft; a gear shifting shaft gear and a gear shifting duplicate gear are mounted on the gear shifting shaft; a driving gear, a reverse gear duplicate gear, a gearshift bull gear and a gearshift pinion are mounted on the auxiliary variable-speed shaft; a driven gear is mounted on the output shaft; gears are adjusted through axial movement of the gear shifting duplicate gear and the gear shifting pinion, forward rotation of the output shaft can be achieved, reverse rotation of the output shaft can also be achieved, operation flexibility is higher, and complex operation requirements can be met; the PTO gearbox outputs four positive rotation speeds and two negative rotation speeds, totally six stages of rotation speeds are achieved, more kinds of agricultural implements can be matched, and the adaptive range is wide; the tractor is provided with the PTO gearbox of the structure and has the same technical effect.

Description

Technical Field

[0001] This utility model relates to the field of tractor gearbox technology, specifically to a PTO gearbox and a tractor. Background Technology

[0002] Tractors are important agricultural machines widely used in agricultural production. A tractor consists of an engine and a PTO (Power Toggle) gearbox connected together. By adjusting the gearbox, different speeds can be output, and various PTO speeds can be matched with different agricultural implements, suitable for various operating modes. Existing small and medium-sized tractor PTO gearboxes can output two or three speeds, and the output shaft rotates in the same direction. However, in some agricultural production scenarios, the PTO gearbox output shaft needs to have a reverse function. For example, some specialized equipment (such as two-way lawnmowers) requires alternating forward and reverse power operation, and if agricultural implements (such as plows and harrows) are stuck by foreign objects, a short-term reverse rotation can help them get out of trouble. Existing small and medium-sized tractor PTO gearboxes do not have a reverse function, cannot adjust the output shaft rotation direction, lack operational flexibility, and are difficult to adapt to complex operating needs. Utility Model Content

[0003] The first objective of this utility model is to provide a PTO gearbox that addresses the problems of existing PTO gearboxes in small and medium-sized tractors lacking a reverse function, unable to adjust the output shaft rotation direction, having insufficient operational flexibility, and being difficult to adapt to complex operational needs. The second objective of this utility model is to provide a tractor.

[0004] To achieve the aforementioned primary objective, the technical solution adopted by this utility model is as follows:

[0005] A PTO (Push-Turn-Off) transmission includes a housing; a main shaft, a shift shaft, a secondary transmission shaft, and an output shaft are rotatably mounted on the housing; a reverse gear, a low gear, and a high gear are fixedly mounted on the main shaft, and a main shaft gear is rotatably mounted axially; a shift shaft gear is fixedly mounted on the shift shaft, and a double shift gear is circumferentially slidably mounted thereon; a drive gear is fixedly mounted on the secondary transmission shaft, a double reverse gear is rotatably mounted axially, and a pinion is circumferentially fixed; a driven gear is fixedly mounted on the output shaft; and the double shift gear... It includes a first large gear and a first small gear connected together; the reverse double gear includes a second large gear and a second small gear connected together; the reverse gear and the second large gear mesh with each other; the shift shaft gear and the shift pinion do not mesh with each other, but both mesh with the main shaft gear; the driving gear and the driven gear mesh with each other; the shift double gear can be moved axially to the first small gear to mesh with the fast gear to achieve forward rotation of the output shaft at a first speed, or to the first large gear to mesh with the slow gear to achieve forward rotation of the output shaft at a second speed, or to the first large gear to mesh with the second small gear to achieve reverse rotation of the output shaft.

[0006] In this utility model employing the aforementioned technical solution, when the double-gear shifter meshes with the slow gear or the fast gear, the main shaft drives the shift shaft to rotate in the opposite direction, further driving the auxiliary transmission shaft and the output shaft to rotate in sequence, ultimately resulting in the output shaft rotating in the same direction as the main shaft. When the double-gear shifter meshes with the double-gear reverse gear, the reverse gear, the double-gear reverse gear, and the double-gear shifter sequentially drive the main shaft to rotate in the same direction, further driving the auxiliary transmission shaft and the output shaft to rotate in sequence, ultimately resulting in the output shaft rotating in the opposite direction to the main shaft. Compared to the existing technology where the PTO gearbox of small and medium-sized tractors lacks a reverse function, cannot adjust the direction of output shaft rotation, has insufficient operational flexibility, and is difficult to adapt to complex operational needs, this utility model's PTO gearbox, by adjusting the gears, can achieve both forward and reverse rotation of the output shaft, providing greater operational flexibility and adapting to complex operational needs.

[0007] Furthermore, the auxiliary transmission shaft is also equipped with an axially fixed and rotatably mounted shift gear; the main shaft gear is a double gear, including a third large gear and a third small gear connected together; both the shift shaft gear and the shift small gear mesh with the third large gear, and the shift large gear meshes with the third small gear; the shift small gear is axially slidably mounted on the auxiliary transmission shaft; the shift small gear can be axially moved to disengage from the third large gear and engage with the shift large gear to achieve linkage rotation with the shift large gear; when the shift small gear meshes with the third large gear, When the shift double gear is engaged with the slow gear, fast gear, and reverse double gear, two forward speeds and one reverse speed can be achieved on the output shaft. By moving the shift pinion to disengage from the third large gear and engaging it with the shift large gear, and then adjusting the shift double gear to engage with the slow gear, fast gear, and reverse double gear, two other forward speeds and one other reverse speed can be achieved on the output shaft. In this way, the PTO gearbox can output four forward and two reverse speeds, for a total of six speed levels, making it compatible with a wider range of agricultural implements and suitable for various applications.

[0008] Furthermore, a positioning block is provided on the end face of the shift pinion, and a positioning groove is provided on the end face of the shift gear. The positioning block can be inserted into the positioning groove along the axial direction to fix the shift pinion and the shift gear in the circumferential direction. With this setting, the insertion and engagement structure between the shift pinion and the shift gear is simple, easy to manufacture, and the two are reliable to achieve linkage rotation of the shift pinion and the shift gear.

[0009] Furthermore, the shift double gear and the shift shaft, as well as the shift pinion and the auxiliary transmission shaft, are connected by splines; a first retaining ring is installed on the main shaft to axially fix the main shaft gear; a second retaining ring and a third retaining ring are installed on the auxiliary transmission shaft to axially fix the shift large gear and the reverse double gear, respectively.

[0010] Furthermore, the gearbox housing is equipped with a first shift fork mechanism and a second shift fork mechanism; the first shift fork mechanism is connected to the shift double gear and is used to drive the shift double gear to move axially; the second shift fork mechanism is connected to the shift pinion and is used to drive the shift pinion to move axially; by setting the first shift fork mechanism and the second shift fork mechanism, it is convenient for the operator to adjust the shifting of the PTO gearbox.

[0011] Furthermore, a clutch is installed inside the housing, through which the power output shaft of the tractor engine is connected to the main shaft.

[0012] Furthermore, the housing includes a front cover, a rear cover, and a partition between them; the main shaft, shift shaft, auxiliary transmission shaft, and output shaft are all rotatably mounted on the housing via two bearings, which are respectively mounted on the partition and the rear cover; the clutch is installed between the front cover and the partition; the housing structure is rationally laid out, facilitating the installation and disassembly of each shaft and the clutch.

[0013] To achieve the second objective, the present invention adopts the following technical solution:

[0014] A tractor including the aforementioned PTO gearbox.

[0015] Compared with the prior art, the beneficial effects of this utility model are as follows: by adjusting the gear, the output shaft can be rotated forward or backward, which is more flexible in operation and can adapt to complex operation needs; this PTO gearbox outputs four forward and two reverse speeds, for a total of six speed levels, which can be matched with more types of agricultural machinery and has a wide range of applicability; the tractor has the same technical effect as the aforementioned PTO gearbox. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of the present invention;

[0017] Figure 2 This is an exploded view of the present invention;

[0018] Figure 3 for Figure 2 Enlarged view of A in the middle;

[0019] Figure 4 This is a schematic diagram of the first transmission path of this utility model;

[0020] Figure 5 This is a schematic diagram of the second transmission path of this utility model;

[0021] Figure 6 This is a schematic diagram of the third transmission path of this utility model;

[0022] Figure 7 This is a schematic diagram of the fourth transmission path of this utility model;

[0023] Figure 8 This is a schematic diagram of the fifth transmission path of this utility model;

[0024] Figure 9 This is a schematic diagram of the sixth transmission path of this utility model;

[0025] Figure 10 This is a schematic diagram of the shift pinion.

[0026] Figure 11 This is a schematic diagram of the shift gear.

[0027] The markings in the diagram are: 01-box body, 011-front end cover, 012-rear end cover, 013-partition plate, 02-first shift fork mechanism, 03-second shift fork mechanism, 04-clutch, 1-main shaft, 2-shift shaft, 3-secondary transmission shaft, 4-output shaft, 5-reverse gear, 6-slow gear, 7-fast gear, 8-main shaft gear, 9-shift shaft gear, 10-double shift gear, 11-drive gear, 12-double reverse gear, 13-small shift gear, 131-positioning block, 132-second annular groove, 14-driven gear, 15-large shift gear, 151-positioning groove. Detailed Implementation

[0028] The present invention will now be described in detail with reference to the accompanying drawings.

[0029] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0030] Example 1: This example provides a PTO transmission, such as... Figures 1-11As shown, the device includes a housing 01, on which a main shaft 1, a shift shaft 2, a secondary transmission shaft 3, and an output shaft 4 are rotatably mounted. A reverse gear 5, a slow gear 6, and a fast gear 7 are fixedly mounted on the main shaft 1, and a main shaft gear 8 is rotatably mounted axially. A shift shaft gear 9 is fixedly mounted on the shift shaft 2, and a double shift gear 10 is circumferentially slidably mounted on it. A drive gear 11 is fixedly mounted on the secondary transmission shaft 3, a double reverse gear 12 is rotatably mounted axially, and a small shift gear 13 is circumferentially fixed. A driven gear 14 is fixedly mounted on the output shaft 4. The double shift gear... 10 includes a first large gear and a first small gear connected together; the reverse double gear 12 includes a second large gear and a second small gear connected together; the reverse gear 5 meshes with the second large gear; the shift shaft gear 9 and the shift pinion 13 do not mesh with each other, but both mesh with the main shaft gear 8; the driving gear 11 and the driven gear 14 mesh together; the shift double gear 10 can be moved axially to the first small gear meshing with the fast gear 7 to achieve forward rotation of the output shaft 4 at a first speed, or moved to the first large gear meshing with the slow gear 6 to achieve forward rotation of the output shaft 4 at a second speed, or moved to the first large gear meshing with the second small gear to achieve reverse rotation of the output shaft 4;

[0031] The shift pinion 13 can be completely fixed on the auxiliary transmission shaft 3. In this case, the PTO transmission can only output two forward speeds and one reverse speed. To further expand the applicable scenarios of the PTO transmission, in this embodiment, the shift pinion 13 is configured to slide axially. In addition, the auxiliary transmission shaft 3 is also provided with an axially fixed and rotatably mounted shift gear 15. The main shaft gear 8 is a double gear, including a third large gear and a third small gear connected together. The shift shaft gear 9 and the shift pinion 13 are both meshed with the third large gear, and the shift gear 15 is meshed with the third small gear. The shift pinion 13 can be slidably mounted on the auxiliary transmission shaft 3 axially. The shift pinion 13 can be moved axially to disengage from the third large gear and engage with the shift gear 15 to achieve linkage rotation with the shift gear 15. In this case, the PTO transmission can output four forward speeds and two reverse speeds.

[0032] Specifically, the transmission path that outputs four forward rotation speeds is as follows: Figures 4-7 As shown, the transmission path that outputs two reverse rotation speeds is as follows: Figures 8-9 As shown; Figures 4-9 As shown, power is input from the left end of the main shaft 1 and output from the right end of the output shaft 4; the reverse gear 5, slow gear 6, fast gear 7 and main shaft gear 8 are arranged on the main shaft 1 from left to right; the shift double gear 10 and shift shaft gear 9 are arranged on the shift shaft 2 from left to right; and the drive gear 11, reverse double gear 12, shift large gear 15 and shift small gear 13 are arranged on the auxiliary transmission shaft 3 from left to right.

[0033] The first transmission path is as follows: Figure 4 As shown, the transmission is carried out in the following order: main shaft 1, slow gear 6, first large gear of double shift gear 10, shift shaft 2, shift shaft gear 9, third large gear of main shaft gear 8, shift pinion 13, auxiliary transmission shaft 3, driving gear 11, driven gear 14, and output shaft 4.

[0034] The second transmission path is as follows: Figure 5 As shown, the transmission is carried out in the following order: main shaft 1, fast gear 7, first pinion of double shift gear 10, shift shaft 2, shift shaft gear 9, third large gear of main shaft gear 8, shift pinion 13, auxiliary transmission shaft 3, driving gear 11, driven gear 14, and output shaft 4.

[0035] The third transmission path is as follows: Figure 6 As shown, the transmission is carried out in the following order: main shaft 1, slow gear 6, first large gear of double shift gear 10, shift shaft 2, shift shaft gear 9, third large gear of main shaft gear 8, third small gear of main shaft gear 8, shift large gear 15, shift small gear 13, auxiliary transmission shaft 3, driving gear 11, driven gear 14, output shaft 4;

[0036] The fourth transmission path is as follows Figure 7 As shown, the transmission is carried out in the following order: main shaft 1, fast gear 7, first small gear of double shift gear 10, shift shaft 2, shift shaft gear 9, third large gear of main shaft gear 8, third small gear of main shaft gear 8, shift large gear 15, shift small gear 13, auxiliary transmission shaft 3, driving gear 11, driven gear 14, output shaft 4;

[0037] The fifth transmission path is as follows Figure 8 As shown, the transmission is carried out in the following order: main shaft 1, reverse gear 5, the second large gear of reverse double gear 12, the second small gear of reverse double gear 12, the first large gear of shift double gear 10, shift shaft 2, shift shaft gear 9, the third large gear of main shaft gear 8, shift small gear 13, auxiliary transmission shaft 3, driving gear 11, driven gear 14, and output shaft 4.

[0038] The sixth transmission path is as follows Figure 9 As shown, the transmission is carried out in the following order: main shaft 1, reverse gear 5, the second large gear of reverse double gear 12, the second small gear of reverse double gear 12, the first large gear of shift double gear 10, shift shaft 2, shift shaft gear 9, the third large gear of main shaft gear 8, the third small gear of main shaft gear 8, shift large gear 15, shift small gear 13, auxiliary transmission shaft 3, driving gear 11, driven gear 14, and output shaft 4.

[0039] A positioning block 131 is provided on the end face of the shift pinion 13, and a positioning groove 151 is provided on the end face of the shift gear 15. The positioning block 131 can be inserted into the positioning groove 151 along the axial direction to fix the shift pinion 13 and the shift gear 15 in the circumferential direction. In this embodiment, three positioning blocks 131 are provided on the end face of the shift pinion 13 and three positioning grooves 151 are provided on the end face of the shift gear 15. The positioning blocks 131 and the positioning grooves 151 correspond one-to-one, and their shapes, sizes and positions are matched with each other.

[0040] The shift double gear 10 and the shift shaft 2, as well as the shift pinion 13 and the auxiliary transmission shaft 3, are connected by splines. A first retaining ring is installed on the main shaft 1 to axially fix the main shaft gear 8. A second retaining ring and a third retaining ring are installed on the auxiliary transmission shaft 3 to axially fix the shift large gear 15 and the reverse double gear 12, respectively. The first, second, and third retaining rings are common fasteners used for axial positioning of parts on the shaft, and will not be described in detail here.

[0041] The housing 01 is provided with a first shift fork mechanism 02 and a second shift fork mechanism 03; the first shift fork mechanism 02 is connected to the shift double gear 10 and is used to drive the shift double gear 10 to move axially; the second shift fork mechanism 03 is connected to the shift pinion 13 and is used to drive the shift pinion 13 to move axially; the first shift fork mechanism 02 and the second shift fork mechanism 03 are both existing structures, commonly used in gearboxes for axial shifting of gears to perform gear shifting; a first annular groove is formed between the first large gear and the first small gear of the shift double gear 10, and the end of the first shift fork mechanism 02 is engaged in the first annular groove; a second annular groove 132 is formed between the end of the positioning block 131 of the shift pinion 13 and the teeth, and the end of the second shift fork mechanism 03 is engaged in the second annular groove 132;

[0042] The housing 01 is equipped with a clutch 04, and the power output shaft of the tractor engine is connected to the main shaft 1 through the clutch 04;

[0043] The housing 01 includes a front cover 011, a rear cover 012, and a partition 013 between them; the main shaft 1, the shift shaft 2, the auxiliary transmission shaft 3, and the output shaft 4 are all rotatably mounted on the housing 01 via two bearings, which are respectively mounted on the partition 013 and the rear cover 012; the clutch 04 is mounted between the front cover 011 and the partition 013.

[0044] Compared to existing technologies where small and medium-sized tractor PTO gearboxes lack a reverse function, cannot adjust the output shaft rotation direction, and have insufficient operational flexibility, making them unsuitable for complex operations, this utility model's PTO gearbox, by adjusting the gears, can achieve both forward and reverse rotation of the output shaft, resulting in greater operational flexibility and adaptability to complex operational needs. Furthermore, this PTO gearbox offers six speed levels (four forward and two reverse), allowing it to be used with a wider variety of agricultural implements and thus has a broad range of applications.

[0045] Example 2: A tractor that includes the above-described PTO gearbox.

[0046] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A PTO gearbox comprising a casing (01), characterized in that: The main shaft (1), the shift shaft (2), the auxiliary transmission shaft (3) and the output shaft (4) are arranged on the box (1) and rotate in parallel; the reverse gear (5), the slow gear (6) and the fast gear (7) are fixedly arranged on the main shaft (1), and the main shaft gear (8) is arranged on the main shaft (1) and rotates in the axial direction; the shift shaft gear (9) is fixedly arranged on the shift shaft (2), and the shift double gear (10) is slidably arranged on the shift shaft (2) in the circumferential direction; the driving gear (11) is fixedly arranged on the auxiliary transmission shaft (3), the reverse double gear (12) is arranged on the auxiliary transmission shaft (3) and rotates in the axial direction, and the shift pinion (13) is arranged on the auxiliary transmission shaft (3) in the circumferential direction; the driven gear (14) is fixedly arranged on the output shaft (4); the shift double gear (10) comprises a first large gear and a first small gear which are connected; the reverse double gear (12) comprises a second large gear and a second small gear which are connected; the reverse gear (5) is engaged with the second large gear; the shift shaft gear (9) and the shift pinion (13) are not engaged with each other, but are engaged with the main shaft gear (8); the driving gear (11) is engaged with the driven gear (14); the shift double gear (10) can be moved in the axial direction to engage the first small gear with the fast gear (7) to realize the positive rotation of the output shaft (4) at a first rotating speed, or to engage the first large gear with the slow gear (6) to realize the positive rotation of the output shaft (4) at a second rotating speed, or to engage the first large gear with the second small gear to realize the reverse rotation of the output shaft (4).

2. The PTO gearbox of claim 1, characterized in that: The shift large gear (15) is arranged on the auxiliary transmission shaft (3) and rotates in the axial direction; the main shaft gear (8) is a double gear comprising a third large gear and a third small gear which are connected; the shift shaft gear (9) and the shift pinion (13) are engaged with the third large gear, and the shift large gear (15) is engaged with the third small gear; the shift pinion (13) is slidably arranged on the auxiliary transmission shaft (3) in the axial direction; the shift pinion (13) can be moved in the axial direction to be disengaged with the third large gear and to be engaged with the shift large gear (15) to realize the linkage rotation with the shift large gear (15).

3. The PTO gearbox of claim 2, characterized in that: The shift pinion (13) is provided with a positioning block (131) on the end face, and the shift large gear (15) is provided with a positioning groove (151) on the end face; the positioning block (131) can be inserted into the positioning groove (151) in the axial direction to realize the fixation of the shift pinion (13) and the shift large gear (15) in the circumferential direction.

4. The PTO gearbox of claim 1, wherein: The shift double gear (10) and the shift shaft (2) are connected by spline, and the shift pinion (13) and the auxiliary transmission shaft (3) are connected by spline; the first clamping spring is arranged on the main shaft (1) and is used for fixing the main shaft gear (8) in the axial direction; the second clamping spring and the third clamping spring are arranged on the auxiliary transmission shaft (3) and are used for fixing the shift large gear (15) and the reverse double gear (12) in the axial direction, respectively.

5. The PTO gearbox of any of claims 2-4, characterized in that: The box (01) is provided with a first shift fork mechanism (02) and a second shift fork mechanism (03); the first shift fork mechanism (02) is connected with the shift double gear (10) and used for driving the shift double gear (10) to move along the axial direction; the second shift fork mechanism (03) is connected with the shift pinion (13) and used for driving the shift pinion (13) to move along the axial direction.

6. The PTO gearbox of claim 1, wherein: The box (01) is provided with a clutch (04), and the power output shaft of the tractor engine is connected with the main shaft (1) through the clutch (04).

7. The PTO gearbox of claim 6, characterized in that: The box (01) comprises a front end cover (011), a rear end cover (012) and a partition plate (013) between the front end cover (011) and the rear end cover (012); the main shaft (1), the shift shaft (2), the auxiliary transmission shaft (3) and the output shaft (4) are all rotatably installed on the box (01) through two bearings, and the two bearings are installed on the partition plate (013) and the rear end cover (012) respectively; the clutch (04) is installed between the front end cover (011) and the partition plate (013).

8. A tractor characterised in that: The PTO gearbox according to any one of claims 1-7.

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