Front power output device of tractor

Abstract

The invention discloses a front power output device of a tractor, and relates to the technical field of agricultural machinery. The device comprises a tractor front frame, a front axle assembly, a front transmission box, a self-adaptive transmission shaft and a terminal transmission box which are connected in sequence. Impurities are prevented from invading through the closed front transmission case, and the failure rate is reduced; a self-adaptive transmission shaft is adopted, and a universal joint and a spline telescopic structure in the self-adaptive transmission shaft can automatically compensate angle and displacement deviations in operation, so that stable and continuous transmission of power in a rugged terrain is guaranteed; and finally, a quick-change spline output shaft of the terminal transmission box is adapted to various front suspension farm tools. The front PTO device effectively solves the problems that a traditional front PTO device is poor in adaptability and high in failure rate, and has the advantages of being stable in transmission, wide in applicability and high in durability.

Description

Technical Field

[0001] This invention relates to the field of power transmission technology for agricultural machinery, specifically a front power take-off device for tractors. Background Technology

[0002] A tractor is a self-propelled power machine used to traction and drive agricultural machinery to complete various mobile operations. It can also be used as a stationary power source. Wheeled tractors are widely used in my country's agricultural machinery field. After many years of development, there has been significant progress in the matching and application of agricultural implements. In particular, the rear-mounted power output and suspension system are relatively complete. However, when equipped with front-drive implements such as harvesters, it is often necessary to transmit power from the rear of the tractor to the front through multiple drive shafts, sprockets, chains and other devices to drive the implements.

[0003] Traditional tractor front power take-off (PTO) devices suffer from the following technical bottlenecks: Poor adaptability: Existing splined shaft outputs only support ISO 500 standard implements, and the maximum working angle of the universal joint is usually no more than 15°, resulting in poor adaptability in complex field terrain and limiting the types of implements and operating scenarios; High failure rate: The open gearbox structure is prone to dust and impurities entering, causing gear wear and transmission failure. According to existing patent CN 1085616A, more than 50% of failures are caused by impurities entering, seriously affecting the reliability and service life of the equipment.

[0004] Therefore, there is an urgent need for a front-mounted PTO device with a reasonable structure, good sealing, strong adaptability, and stable transmission to improve the operating efficiency and reliability of tractors. Summary of the Invention

[0005] This invention addresses the problems existing in the prior art by providing a tractor front power take-off device. It includes a tractor front frame that engages with tractor mounting components.

[0006] The front axle assembly is located below the front frame of the tractor and is used to receive power transmitted from the front axle.

[0007] The front transmission case is located below the front axle assembly. The front transmission case meshes with the gear inside the front axle assembly to achieve initial power transmission and commutation power supply.

[0008] An adaptive drive shaft is configured to be located on the left side of the front transmission box, and a terminal transmission box is configured to be located on the left side of the adaptive drive shaft to transmit power from the front transmission box to the terminal transmission box.

[0009] A terminal transmission box is positioned on the left side of the adaptive drive shaft, and a power output shaft is positioned on the upper part of the terminal transmission box. The power output shaft precisely connects to and drives the suspended implement mounted on the front side.

[0010] Preferably, the tractor front frame includes an outer protective plate, a locking rail, a front axle connecting part, and a mating groove. The front axle connecting part is configured to mate with the front axle assembly. Two symmetrically arranged outer protective plates are provided above the front axle connecting part. A locking rail is provided on the inner side of the outer protective plate. A mating groove is provided on the left side of the locking rail. The locking rail and the mating groove are respectively connected to tractor components.

[0011] Preferably, the front axle assembly includes a power input shaft, a bearing bracket, an outer positioning plate, and a drive assembly. The outer positioning plate is provided on both sides of the bearing bracket and is connected to the tractor front frame. The drive assembly is provided inside the bearing bracket, and the power input shaft is provided on the outer side of the bearing bracket and is connected to the outer tractor drive component.

[0012] Preferably, the front transmission housing includes a transmission housing assembly, a mating gear, an outer bushing, and a lower transmission shaft. The transmission housing assembly is positioned below the front axle assembly. The mating gear is located inside the transmission housing assembly and meshes with the drive components inside the front axle assembly to transmit power to the front axle. The lower transmission shaft is positioned below the mating gear, and an outer bushing is positioned on the outer side of the lower transmission shaft to provide dust protection for the inner side of the lower transmission shaft. The lower transmission shaft is coaxially aligned with the adaptive transmission shaft.

[0013] Preferably, the adaptive transmission shaft internally includes an output transmission sleeve, an arc-shaped ferrule, an inner spline half-shaft, an outer spline half-shaft, and an output transmission shaft. The output transmission sleeve is coaxially fitted with the lower transmission shaft inside the front transmission box. An arc-shaped ferrule is fitted on the left side of the output transmission sleeve. An inner spline half-shaft is fitted on the left side of the arc-shaped ferrule. An outer spline half-shaft is coaxially fitted on the left side of the inner spline half-shaft. An arc-shaped ferrule is fitted on the left side of the outer spline half-shaft. The output transmission shaft is fitted on the left side of the arc-shaped ferrule. The left side of the output transmission shaft is connected to the terminal transmission box.

[0014] Preferably, the arc-shaped ferrule includes a cross shaft, a locking post, a universal joint, and a mating pin. The inner side of the cross shaft is provided with a circular groove, which is coaxially engaged with the inner spline half shaft and the outer spline half shaft, respectively. Circular posts are symmetrically arranged on the left and right sides of the cross shaft. Universal joints with adjustable direction are engaged on the outer side of the circular posts. A mating pin is provided at the rear side of the universal joint, and the mating pin limits the position of the universal joint.

[0015] Preferably, the terminal transmission box includes a connecting drive shaft and a terminal transmission assembly. The connecting drive shaft is coaxially connected with the adaptive drive shaft to transmit power to the inside of the terminal transmission box. The terminal transmission assembly is provided at the upper end of the connecting drive shaft, and a power output shaft is provided above the terminal transmission assembly to output power.

[0016] Preferably, the front transmission box is a closed gearbox, the internal gear set is precision machined and has deceleration and reversing functions, and the box body adopts a sealed structure to prevent external impurities from entering.

[0017] Preferably, the adaptive drive shaft is a universal joint drive shaft, which can automatically adapt to angle changes during transmission and compensate for displacement and posture deviations during tractor operation.

[0018] Preferably, the power output shaft is a splined shaft, forming a quick-change power output interface, which is compatible with various front-suspension agricultural implements.

[0019] Compared with the prior art, the present invention provides a tractor front power take-off device, which has the following beneficial effects:

[0020] 1. The tractor's front power take-off unit can be precisely adapted to agricultural implements. Through the quick-change interface formed by the spline shaft, it supports the rapid connection and power docking of various front-suspension agricultural implements, which significantly expands the tractor's operating range and application scenarios.

[0021] 2. The tractor's front power take-off device has a stable and efficient power transmission function. The enclosed gearbox optimizes the power transmission path, and the adaptive universal joint effectively compensates for angular deviations, reducing power fluctuations and losses, and ensuring the continuity and efficiency of power transmission.

[0022] 3. The structure significantly improves durability during use. The sealed structure design effectively isolates external impurities, reduces gear wear, extends the service life of the device, and reduces maintenance frequency and failure rate. Attached Figure Description

[0023] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0024] Figure 1 This is a schematic diagram of a specific embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the tractor front frame in a specific embodiment of the present invention;

[0026] Figure 3This is a schematic diagram of the front axle assembly in a specific embodiment of the present invention;

[0027] Figure 4 This is a schematic diagram of the front transmission box in a specific embodiment of the present invention;

[0028] Figure 5 This is a schematic diagram of the adaptive drive shaft in a specific embodiment of the present invention;

[0029] Figure 6 This is a schematic diagram of the terminal transmission box in a specific embodiment of the present invention;

[0030] Figure 7 This is a schematic diagram of the component structure of the angle adjustment sleeve in a specific embodiment of the present invention.

[0031] In the diagram: 1. Tractor front frame; 2. Front axle assembly; 3. Front transmission box; 4. Adaptive driveshaft; 5. Terminal transmission box; 6. Power take-off shaft; 1001. Outer protective plate; 1002. Engaging rail; 1003. Front axle connection; 1004. Mating groove; 2001. Power input shaft; 2002. Bearing bracket; 2003. Outer positioning plate; 2004. Drive assembly; 3001. Transmission box assembly; 30 02. Gear; 3003. Outer bushing; 3004. Lower drive shaft; 4001. Input transmission bushing; 4002. Angle adjustment sleeve; 4003. Internal spline half shaft; 4004. External spline half shaft; 4005. Output transmission shaft; 5001. Connecting drive shaft; 5002. Terminal transmission assembly; 6001. Cross shaft; 6002. Arc-shaped locking post; 6003. Universal joint; 6004. Mating pin. Detailed Implementation

[0032] To more clearly illustrate the overall concept of this application, a detailed explanation is provided below with reference to the accompanying drawings.

[0033] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0034] Furthermore, it should be understood in the description of this application that the terms "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of the present invention.

[0035] In this application, unless otherwise expressly 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, an electrical connection, or a communication 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. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0036] In this application, unless otherwise expressly specified and limited, the "above" or "below" of the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. In the description of this specification, references to terms such as "an 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 this application. 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 can be combined in any suitable manner in one or more embodiments or examples.

[0037] Example 1:

[0038] like Figure 1-7 As shown, this embodiment provides a tractor front power take-off device, the core function of which is to reliably transmit the power of the tractor's front axle to the front end to drive various front-suspension agricultural implements. The device includes a tractor front frame 1, a front axle assembly 2, a front transmission box 3, an adaptive driveshaft 4, a terminal transmission box 5, and a power take-off shaft 6.

[0039] The internal component structure and connection relationships of the device are as follows:

[0040] Tractor front frame 1: such as Figure 2 As shown, this component serves as the mounting base for the entire device. It achieves quick engagement with the mounting components at the front of the tractor body via its internal engaging rails 1002 and mating grooves 1004, making installation convenient and reliable. Its front axle connection 1003 is used to position and mount the front axle assembly 2, while the two symmetrically arranged outer protective plates 1001 provide basic protection.

[0041] Front axle assembly 2: such as Figure 3As shown, this assembly is the power input end. It is fixedly mounted on the tractor front frame 1 via outer positioning plates 2003 on both sides. The power input shaft 2001 is connected to the drive components (not shown) of the tractor front axle and receives power from the front axle. Power is transmitted through the drive assembly 2004 (typically a set of bevel gears or cylindrical gears) inside the bearing bracket 2002.

[0042] Front transmission box 3: such as Figure 4 As shown, the gearbox is mounted below the front axle assembly 2 using bolts and other fasteners. The internal gear 3002 meshes with the drive assembly 2004 in the front axle assembly 2, thereby introducing power and achieving the first reversal (typically converting horizontal rotational power into vertical or near-vertical rotation). The gearbox assembly 3001 is a completely enclosed gearbox with a sealed structure, effectively preventing the intrusion of external impurities such as dirt and dust, significantly reducing gear wear and failure rate. The power after reversal and speed adjustment is output through the lower drive shaft 3004, which is supported and dustproofed by the outer bushing 3003.

[0043] Adaptive drive shaft 4: such as Figure 5 and Figure 7 As shown, this drive shaft is used to transmit power from the front transmission box 3 to the terminal transmission box 5. Its left and right ends are coaxially connected to the lower transmission shaft 3004 and the connecting transmission shaft 5001 of the terminal transmission box 5 via output transmission sleeve 4001 and output transmission shaft 4005, respectively. Its core feature lies in the internal spline half-shaft 4003 and external spline half-shaft 4004 connected by a spline pair, allowing the shaft to extend and retract within a certain length range to compensate for distance changes during operation.

[0044] More importantly, the curved retaining sleeves (i.e., universal joint assemblies) at both ends are 4002. For example... Figure 7 As shown, each arc-shaped ferrule 4002 contains components such as a cross shaft 6001, a universal joint 6003, and a mating pin 6004, which together form a universal joint. This allows the adaptive drive shaft 4 to automatically adapt to angular changes during transmission within its maximum working tilt angle (greater than 30°), effectively compensating for displacement and angular deviations caused by bumps and attitude adjustments when the tractor is operating in rugged fields, and ensuring stable and continuous power transmission under non-linear operating conditions.

[0045] Terminal transmission box 5 and power output shaft 6: as follows Figure 6As shown, the terminal transmission box 5 receives power through the adaptive drive shaft 4. Power is transmitted via the connecting drive shaft 5001, and then undergoes a final reversal via the terminal transmission assembly 5002 (usually a pair of bevel gears) within the box, transmitting the power to the vertical power output shaft 6. The power output shaft 6 employs a splined shaft structure, forming a quick-change power output interface conforming to international standards (such as ISO series or SAE series), enabling rapid and precise docking and power transmission with the input sleeves of various front-mounted implements (such as front loaders, snowplows, front-mounted lawnmowers, etc.).

[0046] To verify the excellent performance of this device, especially the adaptive drive shaft 4, in actual operation, the following comparative test was designed to test its performance.

[0047] The test conditions were as follows: a tractor equipped with the front power take-off device of this invention (experimental group) and a tractor equipped with a conventional fixed-angle driveshaft (maximum working tilt angle ≤15°) (control group). A representative rugged field was selected, including naturally formed slopes (approximately 20°), furrows, and soft, uneven sections. The implements were tested using two tractors connected to the same model of front-mounted rotary tiller. A high-precision torque / speed sensor was installed on the power take-off shaft 6, with a data acquisition frequency of 1000Hz to achieve power acquisition functionality.

[0048] Two tractors performed rotary tillage along the same path at the same engine speed (rated PTO speed 540 rpm) and the same working gear. The actual speed fluctuation of the power take-off shaft 6 was recorded throughout the entire operation.

[0049] The specific evaluation indicators are speed fluctuation rate and number of power interruptions:

[0050] The formula for calculating the rotational speed fluctuation rate is as follows:

[0051]

[0052] Where α is the rotational speed fluctuation rate (%), and n max For maximum speed, n min For minimum speed, n 额定 This is the rated speed. The lower the value, the more stable the power transmission and the more uniform the operation of the agricultural implements.

[0053] The calculation logic for the number of power interruptions is: the number of times the drive shaft angle exceeds its limit, causing the universal joint to jam or the speed to drop by more than 25%.

[0054] Test results:

[0055]

[0056] Experimental data fully demonstrates that the adaptive driveshaft 4 described in this invention brings significant performance improvements, including extremely high power stability: the speed fluctuation rate is greatly reduced from 18.5% to 5.2%, indicating that its excellent angle compensation capability can effectively filter the impact and displacement deviation caused by terrain bumps, ensuring continuous and stable power output. This makes the working depth and soil-crushing effect of agricultural implements (such as rotary tillers) more uniform, and significantly improves the quality of work. Excellent terrain adaptability: When the control group encountered a large slope or potholes, the driveshaft angle exceeded its 15° working limit, resulting in universal joint jamming, sudden power drop, or even interruption, seriously affecting work efficiency and continuity. However, the device of this invention did not experience any power interruption throughout the entire test, successfully overcoming the 20° slope condition, proving that its effective working tilt angle far exceeds that of traditional designs, and it is more adaptable to complex fields. High reliability: The elimination of power interruption not only improves efficiency but also avoids the impact and potential damage to the transmission system caused by jamming, extending the service life of the entire device.

[0057] The internal power transmission process and working procedure of the front power take-off device are as follows:

[0058] The power generated by the tractor engine is distributed by the rear axle gearbox and then transmitted to the front axle via the driveshaft. Power from the front axle is input through the power input shaft 2001 of the front axle assembly 2 and transmitted to the front transmission case 3 via the drive assembly 2004. The mating gear 3002 within the front transmission case 3 meshes with the drive assembly 2004, completing power input, reversal, and initial speed adjustment. Power is then output to the adaptive driveshaft 4 via the lower driveshaft 3004.

[0059] The adaptive driveshaft 4, through its spline telescopic structure and universal joints at both ends, overcomes terrain undulations and vehicle body posture changes during tractor operation, smoothly transmitting power to the terminal transmission box 5. The terminal transmission assembly 5002 within the terminal transmission box 5 then reverses direction, ultimately outputting power vertically upwards to the power output shaft 6. The operator connects the spline sleeve of the front-suspension implement to the power output shaft 6, allowing the implement to obtain the appropriate speed and torque for its operational needs, enabling stable operation of various agricultural or engineering tasks.

[0060] When using the tractor's front power take-off (PTO) device, the operator needs to assemble and debug it. During assembly, first, the front axle assembly 2 is securely installed onto the front axle connection part 1003 of the tractor's front frame 1. Then, the entire front frame assembly is installed onto the tractor body via the engaging rail 1002 and mating groove 1004. Next, the front transmission box 3 is installed, ensuring that the meshing clearance between the mating gear 3002 inside and the drive component 2004 of the front axle assembly 2 meets the design standards. Then, the adaptive drive shaft 4 is connected, and finally, the terminal transmission box 5 is installed, ensuring that the coaxiality of each drive shaft is within the allowable error range.

[0061] After mechanical assembly is completed, operational debugging is required: Start the tractor and observe whether each component operates smoothly and without abnormal noises while stationary and traveling at low speeds. Simulate bumpy field conditions to test the effectiveness of the angle compensation function of the adaptive drive shaft 4 and whether there is any jamming or significant fluctuation in power transmission. Replace different models of front suspension implements to test the compatibility and connection reliability of the quick-change interface of the power output shaft 6, and adjust the output speed through the tractor's hydraulic system or gearbox to verify its power adaptation effect to different implements. Based on the test results, the installation position of components or transmission clearance can be fine-tuned to ensure that the device can output power stably and efficiently under various working conditions.

[0062] For any parts not mentioned in this application, existing technologies may be used or referenced.

[0063] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0064] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A tractor front power take-off device, characterized in that, include: The tractor front frame engages with the tractor mounting components. The front axle assembly is located below the front frame of the tractor and is used to receive power transmitted from the front axle. The front transmission case is located below the front axle assembly. The front transmission case meshes with the gear inside the front axle assembly to achieve initial power transmission and commutation power supply. An adaptive drive shaft is configured to be located on the left side of the front transmission box, and a terminal transmission box is configured to be located on the left side of the adaptive drive shaft to transmit power from the front transmission box to the terminal transmission box. A terminal transmission box is positioned on the left side of the adaptive drive shaft, and a power output shaft is positioned on the upper part of the terminal transmission box. The power output shaft precisely connects to and drives the suspended implement mounted on the front side.

2. The front power output device according to claim 1, characterized in that, The tractor front frame includes an outer protective plate, a locking rail, a front axle connection part, and a mating groove. The front axle connection part is configured to mate with the front axle assembly. Two symmetrically arranged outer protective plates are provided above the front axle connection part. A locking rail is provided on the inner side of the outer protective plate. A mating groove is provided on the left side of the locking rail. The locking rail and the mating groove are respectively connected to tractor components.

3. The front power output device according to claim 1, characterized in that, The front axle assembly includes a power input shaft, a bearing bracket, an outer positioning plate, and a drive assembly. The outer positioning plate is located on both sides of the bearing bracket and is connected to the tractor front frame. The drive assembly is located inside the bearing bracket, and the power input shaft is located on the outer side of the bearing bracket and is connected to the outer tractor drive component.

4. The front power output device according to claim 1, characterized in that, The front transmission housing includes a transmission housing assembly, a mating gear, an outer bushing, and a lower transmission shaft. The transmission housing assembly is positioned below the front axle assembly. The mating gear is located inside the transmission housing assembly and meshes with the drive components inside the front axle assembly to transmit power to the front axle. The lower transmission shaft is located below the mating gear, and an outer bushing is located on the outer side of the lower transmission shaft to provide dust protection for the inner side of the lower transmission shaft. The lower transmission shaft is coaxially aligned with the adaptive transmission shaft.

5. The front power output device according to claim 1, characterized in that, The adaptive drive shaft internally includes an output transmission sleeve, an arc-shaped ferrule, an inner spline half-shaft, an outer spline half-shaft, and an output transmission shaft. The output transmission sleeve is coaxially fitted with the lower drive shaft inside the front transmission box. An arc-shaped ferrule is fitted on the left side of the output transmission sleeve. An inner spline half-shaft is fitted on the left side of the arc-shaped ferrule. An outer spline half-shaft is coaxially fitted on the left side of the inner spline half-shaft. An arc-shaped ferrule is fitted on the left side of the outer spline half-shaft. The output transmission shaft is fitted on the left side of the arc-shaped ferrule. The left side of the output transmission shaft is connected to the terminal transmission box.

6. The front power output device according to claim 5, characterized in that, The arc-shaped ferrule includes a cross shaft, a locking post, a universal joint, and a mating pin. The inner side of the cross shaft has a circular groove, which coaxially engages with the inner spline half shaft and the outer spline half shaft, respectively. Circular posts are symmetrically arranged on the left and right sides of the cross shaft. Universal joints with adjustable direction are engaged on the outer side of the circular posts. A mating pin is located at the rear of the universal joint, and the mating pin limits the position of the universal joint.

7. The front power output device according to claim 1, characterized in that, The terminal transmission box includes a connecting drive shaft and a terminal transmission assembly. The connecting drive shaft is coaxially connected with the adaptive drive shaft to transmit power to the inside of the terminal transmission box. The terminal transmission assembly is installed at the upper end of the connecting drive shaft, and a power output shaft is installed above the terminal transmission assembly to output power.

8. The front power output device according to claim 1, characterized in that, The front transmission box is a closed gearbox with precision-machined internal gear sets that have deceleration and reversing functions. The box body adopts a sealed structure to prevent external impurities from entering.

9. The front power output device according to claim 1, characterized in that, The adaptive drive shaft is a universal joint drive shaft, which can automatically adapt to angle changes during transmission and compensate for displacement and posture deviations during tractor operation.

10. The front power output device according to claim 1, characterized in that, The power output shaft is a splined shaft, forming a quick-change power output interface, which is compatible with a variety of front-suspension agricultural implements.

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