Rear power take-off assembly and rear power take-off assembly brake control method

Abstract

This invention proposes a rear power take-off (PTO) assembly and a braking control method for the PTO assembly. The PTO assembly includes an output component, an input component, a clutch, and a brake ring. When the friction plate assembly disengages, the brake ring provides a force opposite to the reset force to the drive mechanism. The braking control method includes the following steps: controlling the drive mechanism to exert a first pushing force on the friction plate assembly of the clutch, causing the friction plate assembly to disengage under the reset force of the reset mechanism; receiving the input shaft speed and output shaft speed of the clutch; calculating a first speed difference based on the input shaft speed and output shaft speed; and controlling the drive mechanism based on the speed difference to cause the friction plate assembly of the clutch to tend towards engagement or disengagement. This control method monitors the clutch speed, and the controller determines the magnitude of the load drag force based on the clutch speed difference. Based on the magnitude of the drag force, it controls the clutch to engage or disengage, thus protecting the brake ring when the load drag force is large and braking the PTO assembly in a timely manner when the load drag force is small.

Description

Technical Field

[0001] This invention relates to the field of vehicle technology, and more particularly to a rear power take-off assembly and a braking control method for the rear power take-off assembly. Background Technology

[0002] This section provides only background information relevant to this disclosure and is not necessarily prior art.

[0003] In existing PTO (Power Take Off) systems, the PTO assembly is mainly used to realize the PTO function on the tractor, that is, by combining the PTO wet clutch and the PTO gear, the engine power is transmitted to the implement through the output shaft of the PTO.

[0004] When the vehicle needs to be started in PTO mode, first engage the PTO clutch. At this time, the clutch will disengage from the brake lever, and the two will no longer be under pressure for braking. Then engage the PTO gear, which will mesh a pair of gears, so that power can be transmitted from the clutch shaft to the gear shaft. The gear shaft is connected to the output shaft, which will ultimately output the power.

[0005] When it's necessary to terminate the PTO function, first disengage the PTO gear to interrupt power to the drive shaft and output shaft. Then, disengage the PTO clutch to disconnect engine power from the drive shaft. At this point, the disengaged clutch end will press against the brake lever. Since the brake lever is held in place by a spring, the spring is further compressed, and the resulting spring force ultimately generates braking torque. Theoretically, the output shaft will stop rotating and no longer transmit power.

[0006] Current CVT braking systems simply rely on the hydraulic cylinder of the clutch to release pressure, disengaging the clutch under the force of the reset spring, and directly pressing the brake lever to generate braking torque. This approach has a significant control risk: when there is equipment with high inertia or significant drag force following the output shaft, because the braking torque is not adjustable, if the braking torque falls below the drag torque at the output shaft position, the brake lever cannot quickly engage the clutch, and both the brake lever and clutch are prone to wear due to sliding friction. Summary of the Invention

[0007] The purpose of this invention is to at least solve the safety problem caused by the inability of the output shaft of existing rear power take-off devices to stop within a short period of time due to the drag force of the load. This purpose is achieved through the following technical solution:

[0008] A first aspect of the present invention provides a rear power take-off assembly, characterized in that it comprises:

[0009] Output components are used to provide power to external devices;

[0010] Input components for connection to the engine drivetrain;

[0011] A clutch includes a friction plate assembly, a drive mechanism, and a reset mechanism. The drive mechanism is capable of driving the friction plate assembly to engage so that the input component is driveably connected to the output component, or driving the friction plate assembly to disengage so that the input component is disengaged from the output component. The reset mechanism is connected to the drive mechanism and is driveably connected to the friction plate assembly through the drive mechanism, and provides a reset force to the friction plate assembly to tend towards separation.

[0012] A brake ring, wherein the drive mechanism abuts against the brake ring when the friction plate assembly separates, and the brake ring provides a force opposite to the reset force to the drive mechanism when the friction plate assembly separates;

[0013] A speed monitoring component, wherein the speed monitoring component is used to monitor the input speed and output speed of the clutch;

[0014] A control device is electrically connected to the drive mechanism and the speed monitoring component, respectively.

[0015] The rear power take-off assembly proposed in this invention eliminates the traditional brake lever and brake lever spring, instead placing a brake ring on one side of the clutch. When the clutch disengages, the drive mechanism of the clutch friction plate assembly makes surface contact with the brake ring. The pressure on the brake ring comes from the reset force of the clutch reset mechanism, and the contact area also expands, increasing the braking torque and thus promptly stopping the output shaft rotation to avoid safety issues. Furthermore, a speed monitoring component monitors the input and output speeds of the clutch, and the controller determines the magnitude of the load's drag force based on the speed difference between the clutches. Based on the magnitude of the drag force, the controller controls the clutch engagement or disengagement to protect the brake ring when the load drag force is high.

[0016] In addition, the rear power take-off assembly according to the present invention may also have the following additional technical features:

[0017] In some embodiments of the present invention, the input component includes an input shaft and an input flange, the input shaft is used to connect to the engine output end, the input flange is sleeved on the input shaft, the output component includes an output shaft, the clutch is sleeved on the output shaft, and the output shaft is capable of drivingly connecting with the input flange when the clutch is engaged, or disconnecting from the driving connection with the input flange when the clutch is disengaged.

[0018] In some embodiments of the present invention, the friction pad assembly includes:

[0019] An intermediate shaft, which is sleeved on the output shaft;

[0020] The main friction plate is sleeved on the intermediate shaft and can slide along the axial direction of the intermediate shaft;

[0021] A secondary friction plate is internally connected to the input flange and can slide along the axial direction of the input flange. When the output shaft is disconnected from the input flange, there is a gap between the main friction plate and the secondary friction plate. When the output shaft is connected to the input flange, the main friction plate and the secondary friction plate are tightly engaged.

[0022] A drive assembly capable of moving toward the friction plate assembly and pushing the main friction plate to engage with the secondary friction plate.

[0023] In some embodiments of the present invention, the intermediate shaft includes an outer ring portion, a connecting portion, and an inner ring portion. The outer ring portion is connected to the inner ring portion through the connecting portion. A receiving cavity is defined between the outer ring portion, the connecting portion, and the inner ring portion. The main friction plate is slidably sleeved on the outer ring portion. The inner ring portion is sleeved on the output shaft. The reset mechanism is disposed within the receiving cavity.

[0024] In some embodiments of the present invention, the driving mechanism includes a hydraulic pump, a control valve, a hydraulic cylinder, and a hydraulic rod. The hydraulic pump and the hydraulic cylinder are connected via a hydraulic oil circuit. The control valve is disposed on the hydraulic oil circuit and electrically connected to the control device. The control valve is used to control the flow rate of the hydraulic oil output to the hydraulic cylinder. The hydraulic rod extends and retracts under the action of the hydraulic cylinder. The extension and retraction direction of the hydraulic rod is set along the sliding direction of the main friction plate, and the extension and retraction direction is opposite to the direction of the reset force provided by the reset mechanism.

[0025] A second aspect of the present invention provides a braking control method for a rear power take-off assembly. Based on the rear power take-off assembly proposed in the first aspect of the present invention, the braking control method includes the following steps:

[0026] The first pushing force of the control drive mechanism on the friction plate assembly of the clutch causes the friction plate assembly to separate under the action of the reset force of the reset mechanism;

[0027] The rotational speed of the input shaft and the rotational speed of the output shaft of the rear power take-off assembly are received.

[0028] The speed difference is calculated based on the rotational speed of the input shaft and the rotational speed of the output shaft;

[0029] The speed difference controls the drive mechanism to cause the friction plate assembly of the clutch to engage or disengage.

[0030] The second aspect of the present invention proposes a rear power take-off assembly braking control method that monitors the input shaft speed and output shaft speed of the clutch, and then the controller determines the magnitude of the load drag force based on the speed difference of the clutch, and controls the clutch to engage or disengage according to the magnitude of the drag force, so as to protect the brake ring when the load drag force is large and brake the rear power take-off assembly in time when the load drag force is small.

[0031] In some embodiments of the present invention, the step of controlling the drive mechanism to engage or disengage the friction plate assembly of the clutch based on the speed difference includes:

[0032] Based on the fact that the first speed difference in the speed difference is greater than the preset speed difference, the drive mechanism is controlled to apply a second pushing force to the friction plate assembly of the clutch, so that the friction plate assembly of the clutch tends to engage.

[0033] In some embodiments of the present invention, after the step of controlling the drive mechanism to engage or disengage the friction plate assembly of the clutch according to the first speed difference, the method further includes the following step:

[0034] The output shaft speed of the clutch is received again;

[0035] Based on the output shaft's rotational speed being within a preset speed range, the drive mechanism is controlled to apply a third pushing force to the clutch's friction plate assembly, causing the clutch's friction plate assembly to tend to separate.

[0036] In some embodiments of the present invention, after the step of controlling the drive mechanism to apply a third pushing force to the friction plate assembly of the clutch based on the output shaft rotation speed being within a preset rotation speed range, so as to cause the friction plate assembly of the clutch to tend to separate, the step further includes:

[0037] Based on the fact that the second speed difference in the speed difference is less than the first speed difference, the drive mechanism is controlled to disengage the friction plate assembly of the clutch.

[0038] In some embodiments of the present invention, the third pushing force is less than the second pushing force and greater than the difference between the reset force and the first pushing force. Attached Figure Description

[0039] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0040] In the attached diagram:

[0041] Figure 1A schematic diagram of the rear power take-off assembly according to an embodiment of the present invention is shown.

[0042] Figure 2 A schematic diagram of the drive structure of the rear power take-off assembly according to an embodiment of the present invention is shown.

[0043] Figure 3 A schematic diagram of the braking control method for the rear power take-off assembly according to an embodiment of the present invention is shown.

[0044] The attached figures are labeled as follows:

[0045] 100: Rear take-off assembly;

[0046] 10: Input shaft; 11: Input flange;

[0047] 20: Main friction plate; 21: Secondary friction plate; 22: Hydraulic cylinder; 23: Hydraulic rod; 24: Reset mechanism; 25: Intermediate shaft; 26: Control valve; 27: Hydraulic pump; 28: Oil tank;

[0048] 30: Output shaft:

[0049] 40: Brake ring;

[0050] 50: Gear shift device. Detailed Implementation

[0051] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0052] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0053] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0054] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented as "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0055] like Figure 1 and Figure 2 As shown, a first aspect of the present invention provides a rear power take-off assembly 100, including an output assembly, an input assembly, a clutch, and a brake ring 40. The output assembly is used to provide power to an external device; the input assembly is used to connect to the power output of an engine; the clutch includes a friction plate assembly, a drive mechanism, and a reset mechanism 24. The drive mechanism is capable of driving the friction plate assembly to engage so that the input assembly is connected to the output assembly, or driving the friction plate assembly to disengage so that the input assembly is disconnected from the output assembly. The reset mechanism 24 is connected to the drive mechanism and transmits a reset force that tends to separate the friction plate assembly through the drive mechanism; the drive mechanism abuts against the brake ring 40 when the friction plate assembly separates, and the brake ring 40 provides a force opposite to the reset force to the drive mechanism when the friction plate assembly separates.

[0056] It is understood that the output component is the sum of the shaft gears and other components connecting the rear power take-off assembly 100 to the external power take-off device, while the input component is the sum of the shaft system components receiving the engine's output power. The clutch can be a friction plate clutch, which connects the transmission structure connected to the main friction plate 20 and the transmission structure connected to the auxiliary friction plate 21 through the tight engagement of the main and auxiliary friction plates 21. The drive mechanism is the mechanism that pushes the main friction plate 20 and the auxiliary friction plate 21 to engage. It can be a hydraulic mechanism, in which hydraulic oil is output from a hydraulic pump to the hydraulic cylinder 22 to push the hydraulic rod 23, thereby pushing the friction plate assembly to engage and achieve clutch engagement to transmit power. Alternatively, it can be a pneumatic mechanism to drive the engagement; for details, please refer to existing technologies. The specific structure of the pneumatic mechanism will not be described here. The reset mechanism 24 is installed on the drive mechanism and provides a reverse elastic force to make the drive mechanism move in the direction of clutch disengagement. The reset mechanism 24 can be a spring or other elastic element, which is clamped between the drive mechanism and the fixed part so that when the hydraulic cylinder 22 stops, it provides a force opposite to the hydraulic cylinder 22, which indirectly drives the friction plate assembly to separate through the drive mechanism, thereby realizing clutch disengagement. The brake ring 40 is a fixed structure installed inside the housing of the rear power take-off assembly 100. The brake ring 40 can be annular or semi-annular and is fixed to the moving path of the drive mechanism through the housing. Specifically, the brake ring 40 can be installed on the path where the drive mechanism is pushed to move by the reset mechanism 24. After the hydraulic cylinder 22 stops, the reset mechanism 24 pushes the drive mechanism to move, and the connecting part of the drive mechanism abuts against the brake ring 40. At this time, the drive mechanism is clamped between the brake ring 40 and the reset mechanism 24. The drive mechanism of the clutch friction plate assembly makes surface contact with the brake ring 40. The pressure of the brake ring 40 comes from the reset force of the clutch reset mechanism 24. The reset force is several times greater than the original brake spring force, and the contact area is also expanded, which increases the braking torque and thus can stop the rotation of the output shaft 30 in time to avoid safety problems.

[0057] In some embodiments of the present invention, the input component includes an input shaft 10 and an input flange 11. The input shaft 10 is used to connect to the engine output end, and the input flange 11 is sleeved on the input shaft 10. The input flange 11 is coaxially arranged with the friction plate assembly and is connected in transmission. The output component includes an output shaft 30, and a clutch is sleeved on the output shaft 30. The output shaft 30 can be connected in transmission with the input flange 11 when the clutch is engaged, or disconnected from the input flange 11 when the clutch is disengaged.

[0058] Specifically, the input shaft 10 is driven and connected to the engine crankshaft to receive the engine's power output. The input flange 11 is fitted onto the input shaft 10, and the coaxial connection between the input flange 11 and the input shaft 10 can be achieved using splines, interference fits, or other methods. The outer edge of the input flange 11 can be connected to the housing of the friction plate assembly. The output shaft 30 is driven and connected to an external device, such as various agricultural machines on a tractor. The clutch is fitted onto the output shaft 30 to achieve a coaxial drive connection between the output shaft 30 and the input shaft 10. More specifically, the main friction plate 20 of the clutch can be connected to the output shaft 30 through the clutch's fixing structure, and the secondary friction plate 21 can be connected to the input flange 11 through another part of the clutch's fixing structure. The drive mechanism achieves a tight engagement of the main friction plate 20 and the secondary friction plate 21 to realize the clutch engagement state, thereby enabling the rotation of the input shaft 10 to be transmitted to the output shaft 30 for output through the clutch.

[0059] In some embodiments of the present invention, the friction pad assembly includes:

[0060] Intermediate shaft 25, which is sleeved on output shaft 30;

[0061] The main friction plate 20 is sleeved on the intermediate shaft 25 in a manner that allows it to slide relative to the intermediate shaft 25.

[0062] The auxiliary friction plate 21 is internally connected to the input flange 11 in a slidable manner relative to the input flange 11. When the output shaft 30 is disconnected from the input flange 11, there is a gap between the main friction plate 20 and the auxiliary friction plate 21. When the output shaft 30 is connected to the input flange 11, the main friction plate 20 and the auxiliary friction plate 21 are tightly engaged.

[0063] The drive assembly is capable of moving toward the friction plate assembly and pushing the main friction plate 20 and the secondary friction plate 21 to engage.

[0064] Understandably, the intermediate shaft 25 is designed according to the specific structure of the clutch. The intermediate shaft 25 can be interference-fitted or keyed onto the output shaft 30. The main friction plate 20 and the auxiliary friction plate 21 can be annular plate structures. The inner edge of the main friction plate 20 is provided with internal teeth that mesh with the external teeth on the intermediate shaft 25, so that the main friction plate 20 can rotate together with the intermediate shaft 25. Under the action of the drive mechanism, the main friction plate 20 can move along the axial direction of the intermediate shaft 25. The outer edge of the auxiliary friction plate 21 can be provided with external teeth that mesh with the internal teeth on the input flange 11, so that the auxiliary friction plate 21 rotates under the rotation of the input flange 11. The auxiliary friction plate 21 can move together with the main friction plate 20 along the axial direction of the input flange 11 under the movement of the main friction plate 20, and is tightly engaged with the main friction plate 20 during the movement. The drive assembly can be hydraulically driven or pneumatically driven. It abuts against the main friction plate 20 through the connecting part. Under the action of the driving force, it pushes the main friction plate 20 to move axially and engage with the secondary friction plate 21, and gradually engages tightly, thereby realizing the clutch engagement for power transmission.

[0065] In some embodiments of the present invention, the intermediate shaft 25 includes an outer ring portion, a connecting portion and an inner ring portion. The outer ring portion is connected to the inner ring portion through the connecting portion. The outer ring portion, the connecting portion and the inner ring portion define a receiving cavity. The main friction plate 20 is sleeved on the outer ring portion in a manner that allows it to slide relative to the outer ring portion. The inner ring portion is sleeved on the output shaft 30. The reset mechanism 24 is disposed in the receiving cavity.

[0066] Specifically, the outer ring is a ring-shaped component located circumferentially outside the inner ring, extending in the same direction as the axial direction of the intermediate shaft 25. Similarly, the inner ring is located radially inside the outer ring and extends axially towards the intermediate shaft 25. The connecting portion integrates the outer ring and the inner ring. The receiving cavity is annularly arranged, and the reset mechanism 24 can be multiple springs arranged circumferentially within the receiving cavity, fixed in the cavity by snap-fit ​​or welding. One end of the spring can be fixedly connected to the connecting portion, and the other end of the spring faces the opening of the receiving cavity and abuts against the fixing portion of the drive mechanism (relative to the pushing friction plate assembly). The receiving cavity allows for a more compact structure of the rear power take-off assembly 100 and provides a fulcrum for the reset device.

[0067] In some embodiments of the present invention, the driving mechanism includes a hydraulic cylinder 22 and a hydraulic rod 23. The hydraulic cylinder 22 extends and retracts under its action. The extension and retraction direction of the hydraulic rod 23 is set along the slidable direction of the main friction plate 20. The reset mechanism 24 can provide a reset force to the hydraulic cylinder 22 opposite to the extension and retraction direction. The driving mechanism adopts a hydraulic drive method. The hydraulic rod 23 is lifted by a hydraulic pump or by outputting hydraulic oil from the oil tank to the hydraulic cylinder 22 to push the main friction plate 20 and the auxiliary friction plate 21 to engage. The driving mechanism is fixed to the output shaft 30 by a housing. One end of the driving mechanism housing abuts against the spring of the reset mechanism 24, and the other end extends radially outward along the output shaft 30 to the axial outer side of the friction plate assembly. The end of the driving mechanism housing away from the spring abuts against the boss on the output shaft 30, so that the driving mechanism is clamped between the spring and the boss of the output shaft 30. The boss is an annular platform structure surrounding the main body of the output shaft 30. The outer edge of the boss and the outer ring of the intermediate shaft 25 have a certain gap in the axial direction of the output shaft 30, so that the drive mechanism can move along the axial direction of the output shaft 30 within the gap.

[0068] Specifically, the drive mechanism also includes a hydraulic pump 27 and a control valve 26. The hydraulic pump 27 is connected to the hydraulic cylinder 22 via a hydraulic oil circuit. The control valve 26 is located on the hydraulic oil circuit and is electrically connected to the control device. The control valve 26 is used to control the flow rate of hydraulic oil output to the hydraulic cylinder 22. The control valve 26 can be a proportional valve. The inlet of the hydraulic pump 27 is connected to the oil tank, and the hydraulic pump 27 also provides hydraulic oil output to the gear shift device 50 of the power take-off.

[0069] In some embodiments of the present invention, the inner edge of the main friction plate 20 is provided with a first internal tooth, the outer edge of the intermediate shaft 25 is provided with a first external tooth that mates with the first internal tooth, the outer edge of the auxiliary friction plate 21 is provided with a second external tooth, and the input flange 11 is provided with a second internal tooth that mates with the second external tooth. The main friction plate 20 rotates synchronously with the intermediate shaft 25 by meshing with the first external tooth of its outer edge with the first external tooth of its inner edge, and the auxiliary friction plate 21 rotates synchronously with the input flange 11 by meshing with the second internal tooth of its outer edge with the second external tooth of its outer edge.

[0070] In some embodiments of the present invention, there are multiple main friction plates 20 and multiple auxiliary friction plates 21, with the main friction plates 20 and auxiliary friction plates 21 spaced apart. The main friction plates 20 are equally spaced on the intermediate shaft 25 along its axial direction, and are connected by meshing to achieve synchronous rotation and axial sliding between the main friction plates 20 and the intermediate shaft 25. Similarly, the multiple auxiliary friction plates 21 are equally spaced on the inner side of the input flange 11 along its axial direction, and are connected by meshing to achieve synchronous rotation and axial sliding between the auxiliary friction plates 21 and the input flange 11. The arrangement of multiple friction plates enhances the engagement tightness of the clutch, improves the adaptability of power transmission, and enhances the reliability and durability of the entire vehicle.

[0071] In some embodiments of the present invention, the rear power take-off assembly 100 further includes a housing, within which a mounting cavity is formed. The input assembly, output assembly, brake ring 40, and clutch are all disposed within the mounting cavity. The housing may be composed of two half-shells, which together define the mounting cavity. The housing has inlets and outlets at both ends for the output shaft 30 and its extension. The interior of the housing has mounting structures such as snap-fit ​​and screw connections for securing internal components. Both the input shaft 10 and the output shaft 30 can be fixed to a mounting platform within the mounting cavity via bearings. Devices such as the hydraulic pump of the hydraulic drive component of the drive mechanism can also be fixed via the mounting structures within the mounting cavity. The contour of the mounting cavity is set according to actual needs and is not limited here.

[0072] In some embodiments of the present invention, the rear power take-off assembly 100 further includes fastening bolts, and the brake ring 40 is connected to the housing via the fastening bolts. By providing a mounting platform inside the housing, the brake ring 40 is fixed to the housing using fastening screws, preventing the brake ring 40 from moving during clutch braking and thus avoiding braking failure, thereby improving the reliability of the device.

[0073] The rear power take-off assembly of the present invention can be applied to agricultural vehicles. Specifically, the agricultural vehicle includes an engine, agricultural machinery and a rear power take-off assembly 100. The rear power take-off assembly 100 is the rear power take-off assembly 100 proposed in the first aspect of the present invention. The agricultural machinery is connected to the engine through the rear power take-off assembly 100.

[0074] When a rear take-off device is needed to provide power to agricultural machinery, the controller controls the hydraulic cylinder 22 of the drive mechanism to apply oil pressure to the hydraulic rod 23, causing the hydraulic rod 23 to extend outward, thereby pushing the main friction plate 20. The main friction plate 20 then closely engages with the secondary friction plate 21 to achieve power transmission. At this time, the input shaft 10 transmits the engine's power to the output shaft 30 via the clutch, and then to the agricultural machinery.

[0075] When power output needs to be stopped, the controller controls the hydraulic cylinder 22 to release hydraulic oil. Under the action of the reset mechanism 24, the hydraulic cylinder 22 moves away from the friction plate assembly, causing the clutch to disengage and the power output from the engine to be interrupted. Under the action of the reset mechanism 24, the drive mechanism abuts against the brake ring 40, so that the drive mechanism is clamped by the brake ring 40 and the reset mechanism 24, thereby slowing down the rotation of the output shaft 30 until it stops, thus achieving braking of the output shaft 30.

[0076] like Figure 3 As shown, a second aspect of the present invention provides a braking control method for a rear power take-off assembly 100. Implemented according to the rear power take-off assembly 100 of the first aspect of the present invention, the braking control method includes the following steps:

[0077] S1: Control the first pushing force of the drive mechanism on the friction plate assembly of the clutch, so that the friction plate assembly is separated under the action of the reset force of the reset mechanism 24;

[0078] S2: Receives the rotational speed of the input shaft 10 and the rotational speed of the output shaft 30 of the power take-off assembly;

[0079] S3: Calculate the speed difference based on the speed of input shaft 10 and the speed of output shaft 30;

[0080] S4: The first speed difference control drive mechanism causes the clutch friction plate assembly to tend to engage or disengage.

[0081] Understandably, the drive mechanism can be hydraulically or pneumatically driven, using pressure to push the push rod out, thereby engaging the main friction plate and the auxiliary friction plate to achieve clutch engagement. The speeds of the input shaft 10 and the output shaft 30 can be obtained by speed sensors installed on the input shaft 10 or the output shaft 30. After calculating the speed difference based on the speed, the controller can control the driving force of the drive mechanism on the friction plate assembly by controlling the flow rate of hydraulic oil output from the drive mechanism to the hydraulic cylinder 22, thereby causing the friction plate assembly of the clutch to tend to engage.

[0082] Specifically, when the first speed difference is large, it can reflect that the load drag force is large, causing the output shaft 30 speed to not follow the input shaft 10 speed drop in time. At this time, the drive mechanism can be controlled to output the driving force again, so that the clutch tends to engage, and the clutch moves away from the brake ring 40 to avoid wear of the brake ring 40.

[0083] The braking control method for the rear power take-off assembly 100 proposed in the second aspect of the present invention monitors the speed of the input shaft 10 and the speed of the output shaft 30 of the clutch, and then the controller determines the magnitude of the drag force of the load based on the speed difference of the clutch, and controls the clutch to engage or disengage according to the magnitude of the drag force, so as to protect the brake ring 40 when the load drag force is large, and brake the rear power take-off assembly 100 in time when the load drag force is small.

[0084] In some embodiments of the present invention, the step of causing the friction plate assembly of the clutch to engage or disengage according to the first speed difference control drive mechanism includes:

[0085] Based on the fact that the first speed difference in the speed difference is greater than the preset speed difference, the control drive mechanism applies a second pushing force to the friction plate assembly of the clutch, causing the friction plate assembly of the clutch to tend to engage.

[0086] It can be understood that when the first speed difference is greater than the preset speed difference within a certain period of time, it is judged that the drag force of the load is large. At this time, in order to prevent wear, the control device will give the control valve 26 a specified current and adjust the hydraulic oil flow output to the hydraulic cylinder 22, so that the end of the clutch moves back to the clutch engagement direction. At this time, the brake ring 40 and the clutch will disengage, thereby preventing wear from occurring.

[0087] In some embodiments of the present invention, after the step of causing the friction plate assembly of the clutch to engage or disengage according to the first speed difference control drive mechanism, the method further includes the step of:

[0088] Based on the output shaft 30's rotational speed being within a preset speed range, the control drive mechanism applies a third pushing force to the clutch friction plate assembly, causing the clutch friction plate assembly to tend to separate.

[0089] When the speed sensor at the output end detects that the speed at the output end has decreased to the preset speed difference due to its own power loss, a specified current is given to the control valve 26 again to adjust the flow of hydraulic oil output to the hydraulic cylinder 22, so that the end of the clutch moves in the clutch separation direction. At this time, the brake ring 40 and the clutch will tend to contact, preparing for the subsequent complete contact between the brake ring 40 and the clutch, and the braking of the rear power take-off assembly 100.

[0090] In some embodiments of the present invention, after the step of controlling the drive mechanism to apply a third pushing force to the friction plate assembly of the clutch, based on the output shaft 30 rotating within a preset speed range, to cause the friction plate assembly of the clutch to tend to separate, the method further includes the following step:

[0091] Based on the fact that the second speed difference is less than the first speed difference, the control drive mechanism is used to separate the friction plate assembly of the clutch.

[0092] Understandably, after the output speed decreases, the speed difference is monitored. If the speed difference continues to decrease, it proves that the drag force of the load is within a reasonable range and the clutch can be fully braked. The control device completely closes the hydraulic oil circuit and drains the oil through the control valve 26, so that the main friction plate abuts against the brake ring 40 and the clutch is braked.

[0093] In some embodiments of the present invention, the third driving force is less than the second driving force and greater than the difference between the reset force and the first driving force. After the rotational speed at the output end decreases, a moderate driving force is output through the drive device, keeping the friction plate assembly in a state between engagement and disengagement, preparing for the next step of fully braking the clutch.

[0094] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A rear power take-off assembly, characterized in that, include: Output components are used to provide power to external devices; Input components for connection to the engine drivetrain; A clutch includes a friction plate assembly, a drive mechanism, and a reset mechanism. The drive mechanism is capable of driving the friction plate assembly to engage so that the input component is driveably connected to the output component, or driving the friction plate assembly to disengage so that the input component is disengaged from the output component. The reset mechanism is connected to the drive mechanism and is driveably connected to the friction plate assembly through the drive mechanism, and provides a reset force to the friction plate assembly to tend towards separation. A brake ring, wherein the drive mechanism abuts against the brake ring when the friction plate assembly separates, and the brake ring provides a force opposite to the reset force to the drive mechanism when the friction plate assembly separates; A speed monitoring component, wherein the speed monitoring component is used to monitor the input speed and output speed of the clutch; The control device is electrically connected to both the drive mechanism and the speed monitoring component. The drive mechanism includes a hydraulic pump, a control valve, a hydraulic cylinder, and a hydraulic rod. The hydraulic pump and the hydraulic cylinder are connected via a hydraulic oil circuit. The control valve is located on the hydraulic oil circuit and electrically connected to the control device. The control valve is used to control the flow rate of the hydraulic oil output to the hydraulic cylinder. The hydraulic rod extends and retracts under the action of the hydraulic cylinder. The extension and retraction direction of the hydraulic rod is set along the sliding direction of the friction plate assembly. The extension and retraction direction is opposite to the direction of the reset force provided by the reset mechanism. The control device is used to determine the magnitude of the load's drag force based on the difference between the input speed and the output speed, and to control the clutch to engage or disengage based on the magnitude of the drag force. The brake ring is a fixed structure disposed within the housing of the rear power take-off assembly. The brake ring is annular or semi-annular and is fixed to the moving path of the drive mechanism by the housing.

2. The rear power take-off assembly according to claim 1, characterized in that, The input assembly includes an input shaft and an input flange. The input shaft is used to connect to the engine output end, and the input flange is sleeved on the input shaft. The output assembly includes an output shaft, and the clutch is sleeved on the output shaft. The output shaft can be driven to the input flange when the clutch is engaged, or disconnected from the input flange when the clutch is disengaged.

3. The rear power take-off assembly according to claim 2, characterized in that, The friction pad assembly includes: An intermediate shaft, which is sleeved on the output shaft; The main friction plate is sleeved on the intermediate shaft and can slide along the axial direction of the intermediate shaft; A secondary friction plate is internally connected to the input flange and can slide along the axial direction of the input flange. When the output shaft is disconnected from the input flange, there is a gap between the main friction plate and the secondary friction plate. When the output shaft is connected to the input flange, the main friction plate and the secondary friction plate are tightly engaged. A drive assembly capable of moving toward the friction plate assembly and pushing the main friction plate to engage with the secondary friction plate.

4. The rear power take-off assembly according to claim 3, characterized in that, The intermediate shaft includes an outer ring portion, a connecting portion, and an inner ring portion. The outer ring portion is connected to the inner ring portion through the connecting portion. A receiving cavity is defined between the outer ring portion, the connecting portion, and the inner ring portion. The main friction plate is sleeved on the outer ring portion in a manner that allows it to slide relative to the outer ring portion. The inner ring portion is sleeved on the output shaft. The reset mechanism is disposed within the receiving cavity.

5. A braking control method for a rear power take-off assembly, implemented according to any one of claims 1 to 4, characterized in that, The braking control method includes the following steps: The first pushing force of the control drive mechanism on the friction plate assembly of the clutch causes the friction plate assembly to separate under the action of the reset force of the reset mechanism; The rotational speed of the input shaft and the rotational speed of the output shaft of the rear power take-off assembly are received. The speed difference is calculated based on the rotational speed of the input shaft and the rotational speed of the output shaft; The speed difference controls the drive mechanism to cause the friction plate assembly of the clutch to engage or disengage. The step of controlling the drive mechanism to engage or disengage the clutch friction plate assembly based on the speed difference includes: Based on the fact that the first speed difference in the speed difference is greater than the preset speed difference, the drive mechanism is controlled to apply a second pushing force to the friction plate assembly of the clutch, so that the friction plate assembly of the clutch tends to engage; The step of controlling the drive mechanism to engage or disengage the clutch friction plate assembly based on the speed difference further includes the following step: Based on the output shaft speed being within a preset speed range, the drive mechanism is controlled to apply a third pushing force to the friction plate assembly of the clutch, causing the friction plate assembly of the clutch to tend to separate. The step of controlling the drive mechanism to apply a third pushing force to the friction plate assembly of the clutch based on the output shaft speed within a preset speed range, so that the friction plate assembly of the clutch tends to separate, further includes the following step: Based on the fact that the second speed difference in the speed difference is less than the first speed difference, the drive mechanism is controlled to disengage the friction plate assembly of the clutch.

6. The rear power take-off assembly braking control method according to claim 5, characterized in that, The third pushing force is less than the second pushing force and greater than the difference between the reset force and the first pushing force.

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