A wet PTO clutch operating device, system, and tractor

Abstract

This utility model discloses a control device, system, and tractor for a wet PTO clutch in the field of clutch operation. It includes a hydraulic pump, a PTO control valve, and a transmission oil tank. One end of the hydraulic pump is connected to the transmission oil tank, and the other end is connected to the PTO control valve. The output end of the PTO control valve is connected to the PTO clutch. The PTO control valve includes a switching valve and a relief valve. The relief valve includes an output port for hydraulic oil within a preset relief pressure and a return port for hydraulic oil beyond the preset relief pressure. The output port is connected to the switching valve, which is mechanically connected to a manual operating device. The control system provided by this utility model has a compact structure, uses hydraulic control to operate the PTO clutch, provides convenient and comfortable operation, reduces damage to the PTO clutch, and uses the relief valve and switching valve to control the output of hydraulic oil to the PTO clutch. Its compact structure occupies little space, eliminates the need for a complex electrical control system, and reduces manufacturing and maintenance costs.

Description

Technical Field

[0001] This utility model relates to the field of clutches, and more particularly to a control device, system, and tractor for a wet PTO clutch. Background Technology

[0002] A tractor PTO (Power Transfer Tolerance) device is a working device that transmits part or even all of the power of a tractor engine to agricultural implements in the form of rotational mechanical energy. It can provide power to harvesting machinery, seeders, fertilizer applicators, and spraying / dusting machinery that do not have their own power units.

[0003] In the PTO engagement control process, the commonly used solution in China is to use a dry clutch, directly engaging the PTO clutch via a clutch pedal or secondary clutch lever. However, the clutch pedal and secondary clutch lever cables are heavy, requiring significant operational effort. Dry clutches also generate enormous impact forces during PTO starting, potentially damaging the PTO and agricultural implements. With the development of electro-hydraulic technology, electronically controlled proportional valves and wet multi-plate clutches have been applied to tractors.

[0004] The solution using wet clutches and electronically controlled valves requires the use of controllers and various monitoring sensors, resulting in a large number of electronically controlled components and a complex system, leading to higher manufacturing and maintenance costs. Utility Model Content

[0005] The purpose of this utility model is to provide a control device, system and tractor for a wet PTO clutch. It has a simple structure, does not require an electronic control system to complete the hydraulic control of the PTO clutch, and has low manufacturing and maintenance costs.

[0006] To solve the above technical problems, the following technical solution is adopted:

[0007] In the first aspect, this utility model provides an operating system for a wet PTO clutch, including a hydraulic pump, a PTO control valve and a transmission oil tank. One end of the hydraulic pump is connected to the transmission oil tank and the other end is connected to the PTO control valve. The output end of the PTO control valve is connected to the PTO clutch.

[0008] The PTO control valve includes a switching valve and a relief valve. The outlet of the relief valve is set with a preset relief pressure according to the control pressure of the PTO clutch. It includes an output port for hydraulic oil passing through the preset relief pressure and a return port for hydraulic oil passing through a pressure greater than the preset relief pressure.

[0009] The output port is connected to the switching valve, which is connected to the manual operating device via mechanical transmission. The return port enters the transmission lubrication passage through the radiator and finally flows back to the transmission oil tank.

[0010] Optionally, the PTO control valve further includes a buffer valve, which controls the pressure build-up time of hydraulic oil to the PTO clutch through a damping orifice to achieve a buffering effect.

[0011] Optionally, an oil suction filter is provided between the hydraulic pump and the transmission oil tank, and an oil inlet filter is provided between the hydraulic pump and the PTO control valve.

[0012] Secondly, this utility model provides an operating device for a wet PTO clutch, including the operating system of the wet PTO clutch as described in any one of the first aspects. The switching valve is provided with a valve stem, which is connected to a manual operating device via a flexible shaft. The manual operating device includes a mounting bracket, a control lever, and a control handle. One end of the control lever is mounted on the mounting bracket via a rotating shaft, and the other end of the control lever is connected to the control handle. The control lever is driven to rotate around the rotating shaft via the control handle, thereby driving the opening and closing of the switching valve.

[0013] Optionally, the valve stem is provided with a positioning slot, which is used to fix the valve stem in the open or closed position.

[0014] Optionally, the manual operating device is further provided with a proximity switch, which is mounted on the mounting bracket. When the lever contacts the proximity switch, it is linked with the engine control system, and the engine can be ignited and started; otherwise, it cannot be started.

[0015] Optionally, the PTO control valve is connected to the PTO clutch via a pressure oil pipe and to the radiator via a lubricating oil pipe.

[0016] Optionally, the transmission oil tank is located inside the transmission, the PTO control is installed on the upper cover of the transmission, the PTO control valve is connected to the transmission oil tank through an oil inlet pipe, and an oil suction filter, the hydraulic pump and the oil inlet filter are installed on the oil inlet pipe.

[0017] Thirdly, this utility model provides a tractor that includes an operating device for a wet PTO clutch as described in any of the second aspects.

[0018] Compared with the prior art, the beneficial effects achieved by this utility model are as follows:

[0019] 1. The operating system provided by this utility model has a compact structure and adopts hydraulic control of the PTO clutch. It is convenient and comfortable to operate, reduces damage to the PTO clutch, and uses an overflow valve and a switching valve to control the output of hydraulic oil to the PTO clutch. The structure is compact and occupies little space. It does not require a complex electrical control system, thus reducing manufacturing and maintenance costs.

[0020] 2. The control device provided by this utility model has a proximity switch installed on the mounting bracket of the control lever. The proximity switch is connected to the engine control system. Whether the engine can be ignited and started is controlled by whether the proximity switch is in contact with the control lever, thus avoiding misoperation. The control lever is connected to the valve stem on the switch valve by a flexible shaft, making it easy to operate and simple in structure. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the operating system of the wet PTO clutch 5 in this embodiment of the present invention.

[0022] Figure 2 This is a schematic diagram of the PTO control valve structure in an embodiment of this utility model;

[0023] Figure 3 This is a schematic diagram of the overall structure of the operating device of the wet PTO clutch 5 in this embodiment of the present invention.

[0024] Figure 4 This is a partial structural diagram of the operating system of the wet PTO clutch 5 in an embodiment of this utility model.

[0025] Explanation of reference numerals in the attached figures:

[0026] 1. Gearbox; 2. Oil inlet pipe; 3. Oil inlet filter; 4. PTO control valve; 41. Relief valve; 42. Switch valve; 43. Buffer valve; 44. Valve stem; 5. Wet PTO clutch; 6. Gearbox upper cover; 7. Pressure oil pipe; 8. Mounting bracket; 9. Rotary shaft; 10. Control lever; 11. Control handle; 12. Flexible shaft; 13. Proximity switch; 14. Suction filter; 15. Hydraulic pump; 16. Radiator. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use.

[0028] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not 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 this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more. In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0029] Example 1

[0030] like Figure 1 , Figure 2 As shown, this embodiment provides an operating system for a wet PTO clutch 5, including a hydraulic pump 15, a PTO control valve 4, and a transmission oil tank. One end of the hydraulic pump 15 is connected to the transmission oil tank, and the other end is connected to the PTO control valve 4. The output end of the PTO control valve 4 is connected to the PTO clutch 5.

[0031] A suction filter 14 is also provided in the oil line between the hydraulic pump 15 and the gearbox oil tank, and an inlet filter 3 is also provided in the oil line between the hydraulic pump 15 and the PTO control valve 4. The hydraulic oil is filtered by the suction filter 14 and the inlet filter 3.

[0032] The PTO control valve 4 includes a switching valve 42, a relief valve 41, and a buffer valve 43. One end of the switching valve 42 is connected to the relief valve 41, and the other end is connected to the PTO clutch 5. By switching the hydraulic oil supply to the PTO clutch 5 on and off, it controls the operation of the PTO clutch 5. The switching valve 42 is mechanically connected to a manual operating device, allowing the operator to manually open and close it. The inlet of the relief valve 41 is connected to the suction filter 14, and the outlet is connected to the switching valve 42. The relief valve 41 controls the pressure of the hydraulic oil entering the PTO clutch 5.

[0033] The outlet of the relief valve 41 is also connected to the radiator 16. By setting a preset relief pressure, the outlet of the relief valve 41 is divided into an output port and a return port. The output port is connected to the switching valve 42, through which hydraulic oil at the preset relief pressure passes. The return port is connected to the radiator 16, through which hydraulic oil at a pressure higher than the preset relief pressure passes. The hydraulic oil flowing out through the return port enters the radiator 16 for cooling. The other end of the radiator 16 is connected to the transmission lubrication passage. The cooled hydraulic oil enters the transmission lubrication passage for lubrication and finally flows back to the transmission oil tank.

[0034] The preset overflow pressure is generally set at around 2MPa. When the pressure is higher than this, the oil overflows and enters the transmission lubrication passage to lubricate the parts.

[0035] After the hydraulic oil acting on the PTO clutch 5 has finished driving the PTO clutch 5, it flows back into the transmission oil tank.

[0036] A buffer valve 43 is installed between the switching valve 42 and the reverse flow valve. The buffer valve 43 achieves the buffering effect through the damping orifice. The damping orifice controls the pressure build-up time of the hydraulic oil to the PTO clutch 5 to achieve the buffering effect, so as to avoid the hydraulic oil entering the PTO clutch 5 with excessive instantaneous impact force, which could damage the PTO clutch 5.

[0037] During operation, the hydraulic pump 15 pressurizes hydraulic oil from the transmission oil tank and pumps it to the PTO clutch 5 to drive it. The hydraulic oil circuit passes through the suction filter 14, the inlet filter 3 and the PTO control valve 4 in sequence. After the PTO clutch 5 finishes working, the hydraulic oil flows back to the transmission oil tank from the internal circuit of the PTO clutch 5. The hydraulic oil overflowing from the overflow valve 41 enters the radiator 16. After the engine drives the radiator 16 to cool and reduce the pressure of the hydraulic oil, the hydraulic oil enters the transmission lubrication passage to play a lubricating role, and finally flows back to the transmission oil tank.

[0038] The operating system provided in this embodiment eliminates the need for additional electronic control systems to hydraulically control the PTO clutch 5. It features a simple structure and low manufacturing and maintenance costs. The damping orifice provides the buffering effect of the PTO control valve 4, while the relief valve 41 provides hydraulic control. Two filters ensure that the hydraulic oil driving the PTO clutch 5 and entering the transmission lubrication channels is free of impurities. Compared to a dry clutch, the operating system for the wet PTO clutch 5 provided in this embodiment is lighter and more comfortable to operate.

[0039] Example 2

[0040] like Figure 3 , Figure 4As shown, this embodiment provides an operating device for a wet PTO clutch 5 based on embodiment one. The manual operating device includes a control lever 10 and a control handle 11. One end of the control lever 10 is rotatably connected to the mounting bracket 8 via a rotating shaft 9. The mounting bracket 8 is set in the vehicle cab. The other end of the control lever 10 is provided with a control handle 11, which is convenient for gripping.

[0041] like Figure 2 , Figure 4 As shown, a valve stem 44 is provided on the switching valve 42. The valve stem 44 is connected to the control lever 10 via a flexible shaft 12. By pushing and pulling the control handle 11 back and forth, the control lever 10 is rotated around the rotation axis 9, thereby driving the valve stem 44 to the closed or open position, realizing the opening or closing of the switching valve 42.

[0042] A positioning slot is provided on the valve stem 44. The positioning slot is used to fix the valve stem 44 in two positions: open and closed. When the control handle 11 is pulled back, the control lever 10 rotates and pulls the valve stem 44 out. When the positioning slot is in the open position, the PTO clutch 5 starts to work and is used to push the control handle 11 forward to close the valve. The PTO clutch 5 stops working.

[0043] A proximity switch 13 is also provided on the mounting bracket 8. The proximity switch 13 detects the position of the control lever 10. When the control lever 10 is rotated to contact the proximity switch 13, the proximity switch 13 is in the engaged state and connected to the engine control system, allowing ignition to be started. When the control lever 10 is rotated to not contact the proximity switch 13, the proximity switch 13 is in the closed state, and ignition cannot be started. The proximity switch 13 can prevent user misoperation.

[0044] The transmission 1 is connected to the oil inlet filter 3 via the oil inlet pipe 2. One end of the oil inlet pipe 2 is connected to the transmission oil tank inside the transmission 1, and the other end is connected to the oil inlet filter 3. A hydraulic pump and a suction filter are also installed on the oil inlet pipe 2. The oil inlet filter 3 is connected to the PTO control valve 4 via an oil circuit. The PTO control valve 4 is connected to the PTO clutch 5 via a pressure oil pipe 7. Both the PTO control valve 4 and the oil inlet filter 3 are mounted on the upper end cover 6 of the transmission.

[0045] The operating device of the wet PTO clutch 5 provided in this embodiment has a simple structure, is lighter and easier to operate and maintain than the dry clutch. The proximity switch 13 is connected to the engine control system to prevent misoperation.

[0046] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A control system for a wet PTO clutch, characterized in that, It includes a hydraulic pump, a PTO control valve, and a transmission oil tank. One end of the hydraulic pump is connected to the transmission oil tank, and the other end is connected to the PTO control valve. The output end of the PTO control valve is connected to the PTO clutch. The PTO control valve includes a switching valve and a relief valve. The outlet of the relief valve is set with a preset relief pressure according to the control pressure of the PTO clutch. It includes an output port for hydraulic oil passing through the preset relief pressure and a return port for hydraulic oil passing through a pressure greater than the preset relief pressure. The output port is connected to the switching valve, which is connected to the manual operating device via mechanical transmission. The return port enters the transmission lubrication passage through the radiator and finally flows back to the transmission oil tank.

2. The operating system for a wet PTO clutch according to claim 1, characterized in that, The PTO control valve also includes a buffer valve, which controls the pressure build-up time of the hydraulic oil to the PTO clutch through a damping orifice to achieve a buffering effect.

3. The operating system for a wet PTO clutch according to claim 1, characterized in that, An oil suction filter is also provided between the hydraulic pump and the transmission oil tank, and an oil inlet filter is also provided between the hydraulic pump and the PTO control valve.

4. An operating device for a wet PTO clutch, characterized in that, The operating system includes the wet PTO clutch according to any one of claims 1-3, wherein the switching valve is provided with a valve stem, the valve stem is connected to a manual operating device via a flexible shaft, the manual operating device includes a mounting bracket, a control lever and a control handle, one end of the control lever is mounted on the mounting bracket via a rotating shaft, and the other end of the control lever is connected to the control handle, the control lever is driven to rotate around the rotating shaft by the control handle, thereby driving the opening and closing of the switching valve.

5. The operating device for the wet PTO clutch according to claim 4, characterized in that, The valve stem is provided with a positioning slot, which is used to fix the valve stem in the open or closed position.

6. The operating device for a wet PTO clutch according to claim 4, characterized in that, The manual operating device is also equipped with a proximity switch, which is mounted on the mounting bracket. When the lever contacts the proximity switch, it is linked with the engine control system, and the engine can be ignited and started; otherwise, it cannot be started.

7. The operating device for a wet PTO clutch according to claim 4, characterized in that, The PTO control valve is connected to the PTO clutch via a pressure oil pipe and to the radiator via a lubricating oil pipe.

8. The operating device for a wet PTO clutch according to claim 4, characterized in that, The transmission oil tank is located inside the transmission. The PTO control valve is installed on the upper cover of the transmission. The PTO control valve is connected to the transmission oil tank through an oil inlet pipe. An oil suction filter, the hydraulic pump, and the oil inlet filter are installed on the oil inlet pipe.

9. A tractor comprising an operating device for a wet PTO clutch as described in any one of claims 5-8.

Images