Integrated hydraulic transmission system and intelligent monitoring and control method for skid steer loader

Abstract

The present invention provides an integrated hydraulic transmission system and intelligent monitoring and control method for a skid loader, and relates to the technical field of skid loaders. The integrated hydraulic transmission system for a skid loader of the present invention is designed for a skid loader innovatively designed by the applicant's research and development team. Through modular design, it integrates various hydraulic system modules to make the hydraulic transmission system efficient and energy-saving, compact and flexible, precisely controllable, reliable and durable, so as to achieve a good match between the hydraulic transmission system and the hydraulic terminal. It is suitable for engineering machinery such as skid loaders that have high requirements for space, energy efficiency and versatility, and meets the compact design requirements of skid loaders to the greatest extent. The intelligent monitoring and control method for the hydraulic transmission system of the present invention intelligently monitors the hydraulic transmission system and can automatically self-lock and warn when the hydraulic transmission system is working abnormally, thereby improving the intelligence level of the hydraulic transmission system of the skid loader and improving operation safety.

Description

Technical Field

[0001] The present invention relates to the technical field of skid-steer loaders, and in particular to an integrated hydraulic transmission system and an intelligent monitoring and control method for a skid-steer loader. Background Art

[0002] A skid-steer loader, also known as a multi-purpose engineering vehicle or multi-purpose engineering machine, is a compact, agile, and compact construction machine. Utilizing the linear speed difference between the wheels, a skid-steer loader achieves steering. It is primarily used in narrow, uneven terrain, and where the workload changes frequently. It is widely used in urban infrastructure, roads, construction sites, factory workshops, warehouses, docks, ship decks, and garden farms. By replacing various attachments, a skid-steer loader can perform various tasks, including scraping, stacking, lifting, excavating, drilling, crushing, grabbing, loosening and trenching, road sweeping, and road compaction.

[0003] The compact structure of existing skid-steer loaders limits their operating range, resulting in insufficient forklift reach, unloading height, and unloading distance, resulting in a limited operating range. Furthermore, most existing skid-steer loaders directly articulate the hydraulic cylinder with the boom front and attachment frame, limiting the attachment's freedom of movement and enabling only a single basic degree of freedom. This makes it difficult to connect different attachment types and adapt to various working conditions.

[0004] The applicant's R&D team innovatively designed a skid-steer loader to enhance its operating range and freedom of movement. However, the team also discovered that the hydraulic transmission systems of existing skid-steer loaders typically utilize multiple metering pumps to independently supply oil to each hydraulic terminal. This system is poorly matched to the hydraulic terminals of skid-steer loaders and cannot fully meet the skid-steer loader's compact design requirements. Furthermore, the hydraulic transmission system lacks intelligent monitoring, resulting in a low level of intelligence and operational safety, requiring further improvement.

[0005] The above information disclosed in this background technology is only used to increase the understanding of the background technology of this application. Therefore, it may contain information that does not constitute the prior art known to ordinary technicians in this field. Summary of the Invention

[0006] The purpose of the present invention is to provide an integrated hydraulic transmission system and intelligent monitoring and control method for a skid steer loader, so as to achieve a good match between the hydraulic transmission system and the hydraulic terminal, and to meet the compact design requirements of the skid steer loader to the greatest extent; and to perform intelligent monitoring of the hydraulic transmission system to improve operational safety.

[0007] In order to achieve the above objectives, the technical solutions adopted by the present invention are as follows:

[0008] An integrated hydraulic transmission system for a skid loader, comprising:

[0009] A hydraulic supply unit is used to supply hydraulic oil to the boom swing hydraulic unit, boom telescopic hydraulic unit, attachment flip hydraulic unit, and attachment rotation hydraulic unit connected in parallel;

[0010] The boom swing hydraulic unit includes a swing hydraulic cylinder. The boom swing hydraulic unit is used to drive the swing hydraulic cylinder to extend and retract, thereby driving the main boom to swing up and down relative to the vehicle chassis;

[0011] The boom telescopic hydraulic unit includes a telescopic hydraulic cylinder, which is used to drive the telescopic hydraulic cylinder to extend and retract, thereby driving the telescopic boom to move forward and backward relative to the main boom;

[0012] The attachment turning hydraulic unit includes a turning hydraulic cylinder, which is used to drive the turning hydraulic cylinder to extend and retract, thereby driving the attachment support base to swing up and down relative to the end of the telescopic boom;

[0013] An attachment rotation hydraulic unit includes a hydraulic motor, the attachment rotation hydraulic unit is used to drive the output end of the hydraulic motor to rotate, thereby driving the attachment to rotate relative to the attachment support base;

[0014] The hydraulic oil return unit is used to return oil to the boom swing hydraulic unit, boom telescopic hydraulic unit, attachment flip hydraulic unit and attachment rotation hydraulic unit.

[0015] Preferably, one end of the main boom is articulated to the vehicle chassis, one end of the swing hydraulic cylinder is articulated to the vehicle chassis, and the other end of the swing hydraulic cylinder is articulated to the other end of the main boom;

[0016] The telescopic boom is slidably matched with the main boom, and the telescopic boom can move forward and backward relative to the main boom, and the two ends of the telescopic hydraulic cylinder are respectively connected to the main boom and the telescopic boom;

[0017] The lower end of the attachment support base is hinged to the end of the telescopic boom, and the two ends of the tilting hydraulic cylinder are hinged to the upper end of the attachment support base and the telescopic boom respectively;

[0018] The attachment is rotatably connected to the attachment support base, the hydraulic motor is arranged on the attachment support base, and the output end power of the hydraulic motor is connected to the attachment.

[0019] Preferably, the hydraulic supply unit includes a hydraulic pump, an oil inlet pipeline and an oil outlet pipeline;

[0020] The oil inlet end of the hydraulic pump is connected to the oil tank via an oil inlet pipeline, the oil outlet end of the hydraulic pump is connected to one end of an oil outlet pipeline, and the oil outlet pipeline is connected to the oil tank via a first oil return pipeline. A proportional overflow valve is provided on the first oil return pipeline.

[0021] Preferably, the boom swing hydraulic unit further includes a first proportional directional valve, a first solenoid valve, a first one-way valve and a first accumulator;

[0022] The rodless chamber oil port and the rod chamber oil port of the swing hydraulic cylinder are respectively connected to the A1 port and B1 port of the first proportional directional valve, the P1 port and T1 port of the first proportional directional valve are respectively connected to the A2 port and B2 port of the first solenoid valve, the P2 port of the first solenoid valve is connected to the other end of the oil outlet pipeline via the first oil outlet branch, a first check valve is arranged on the first oil outlet branch, a first accumulator is connected between the P2 port of the first solenoid valve and the first check valve on the first oil outlet branch, and the T2 port of the first solenoid valve is connected to the hydraulic oil return unit.

[0023] Preferably, the boom telescopic hydraulic unit further includes a second proportional directional valve, a second solenoid valve, a second one-way valve and a second accumulator;

[0024] The rodless chamber oil port and the rod chamber oil port of the telescopic hydraulic cylinder are respectively connected to the A2 port and B2 port of the second proportional directional valve, the P2 port and T2 port of the second proportional directional valve are respectively connected to the A3 port and B3 port of the second solenoid valve, the P3 port of the second solenoid valve is connected to the other end of the oil outlet pipeline via the second oil outlet branch, a second one-way valve is arranged on the second oil outlet branch, a second accumulator is connected between the P3 port of the second solenoid valve and the second one-way valve on the second oil outlet branch, and the T3 port of the second solenoid valve is connected to the hydraulic oil return unit.

[0025] Preferably, the attachment turning hydraulic unit further includes a third proportional directional valve, a third solenoid valve, a third one-way valve and a third accumulator;

[0026] The rodless chamber oil port and the rod chamber oil port of the flip hydraulic cylinder are respectively connected to the A5 port and B5 port of the third proportional directional valve, the P5 port and T5 port of the third proportional directional valve are respectively connected to the A6 port and B6 port of the third solenoid valve, the P6 port of the third solenoid valve is connected to the other end of the oil outlet pipeline via the third oil outlet branch, a third check valve is arranged on the third oil outlet branch, a third accumulator is connected between the P6 port of the third solenoid valve and the third check valve on the third oil outlet branch, and the T6 port of the third solenoid valve is connected to the hydraulic oil return unit.

[0027] Preferably, the attachment rotation hydraulic unit further includes a fourth proportional directional valve, a fourth solenoid valve, a fourth one-way valve and a fourth accumulator;

[0028] The two oil ports of the hydraulic motor are respectively connected to the A7 port and B7 port of the fourth proportional directional valve, the P7 port and T7 port of the fourth proportional directional valve are respectively connected to the A8 port and B8 port of the fourth solenoid valve, the T8 port of the fourth solenoid valve is connected to the other end of the oil outlet pipeline via the fourth oil outlet branch, a fourth check valve is arranged on the fourth oil outlet branch, the fourth accumulator is connected between the T8 port of the fourth solenoid valve and the fourth check valve on the fourth oil outlet branch, and the P8 port of the fourth solenoid valve is connected to the hydraulic oil return unit.

[0029] Preferably, the hydraulic oil return unit includes a collecting valve and an oil return pipeline;

[0030] The T2 port of the first solenoid valve is connected to the oil inlet of the collecting valve via the first oil return branch, the T3 port of the second solenoid valve is connected to the oil inlet of the collecting valve via the second oil return branch, the T6 port of the third solenoid valve is connected to the oil inlet of the collecting valve via the third oil return branch, the P8 port of the fourth solenoid valve is connected to the oil inlet of the collecting valve via the fourth oil return branch, and the oil outlet of the collecting valve is connected to the oil tank via the oil return pipeline.

[0031] Preferably, a heater is provided on the oil inlet pipeline, a first temperature difference switch is connected to the oil inlet and the oil outlet of the heater, and a first flow sensor is provided on the oil outlet pipeline;

[0032] The pipeline between the rodless chamber oil port of the swing hydraulic cylinder and the A1 port of the first proportional directional valve is connected with a first pressure sensor, a first temperature sensor and a second flow sensor;

[0033] The pipeline between the rodless chamber oil port of the telescopic hydraulic cylinder and the A2 port of the second proportional directional valve is connected with a second pressure sensor, a second temperature sensor and a third flow sensor;

[0034] The pipeline between the rod chamber oil port of the tilting hydraulic cylinder and the B5 port of the third proportional directional valve is connected to a third pressure sensor, a third temperature sensor and a fourth flow sensor;

[0035] A fourth pressure sensor, a fourth temperature sensor, and a fifth flow sensor are connected to the pipeline between an oil port of the hydraulic motor and the B7 port of the fourth proportional directional valve;

[0036] A cooler is provided on the oil return pipeline, and a second temperature difference switch is connected to the oil inlet and the oil outlet of the cooler;

[0037] The oil return line is connected to the oil inlet of the electromagnetic reversing valve, and the two oil outlets of the electromagnetic reversing valve are connected to the oil tank through the fifth oil return branch and the sixth oil return branch respectively. A filter is provided on the fifth oil return branch, and the differential pressure switch is connected to the oil inlet and oil outlet of the filter;

[0038] The controller respectively connects the heater, the first temperature differential switch, the first flow sensor, the first pressure sensor, the first temperature sensor, the second flow sensor, the second pressure sensor, the second temperature sensor, the third flow sensor, the third pressure sensor, the third temperature sensor, the fourth flow sensor, the fourth pressure sensor, the fourth temperature sensor, the fifth flow sensor, the cooler, the second temperature differential switch, the electromagnetic reversing valve and the pressure differential switch.

[0039] A method for intelligent monitoring and control of a hydraulic transmission system is provided for monitoring and controlling the above-mentioned integrated hydraulic transmission system of a skid loader. The method operates as follows:

[0040] The controller monitors the oil temperature at the oil inlet and oil outlet of the heater in real time via the first temperature differential switch, and monitors the flow rate in real time via the first flow sensor; when the oil temperature at the oil inlet of the heater is within a set temperature range, the heater does not operate; when the oil temperature at the oil inlet of the heater is lower than the set temperature, the controller controls the heater to operate; when the oil temperature at the oil inlet and / or oil outlet of the heater exceeds the set temperature, or when the oil temperature difference between the oil inlet and oil outlet of the heater deviates from the set temperature range, or when the flow rate exceeds a set threshold, the controller triggers the hydraulic supply unit to self-lock and issues a warning signal;

[0041] The controller monitors the oil pressure, oil temperature and flow rate in real time via the first pressure sensor, the first temperature sensor and the second flow rate sensor. When any one of the oil pressure, oil temperature and flow rate exceeds the set threshold, the controller triggers the boom swing hydraulic unit to self-lock and issues a warning signal.

[0042] The controller monitors the oil pressure, oil temperature and flow rate in real time via the second pressure sensor, the second temperature sensor and the third flow rate sensor. When any one of the oil pressure, oil temperature and flow rate exceeds the set threshold, the controller triggers the boom extension hydraulic unit to self-lock and issues a warning signal.

[0043] The controller monitors the oil pressure, oil temperature, and flow rate in real time via the third pressure sensor, the third temperature sensor, and the fourth flow rate sensor. When any one of the oil pressure, oil temperature, and flow rate exceeds a set threshold, the controller triggers the attachment's turning hydraulic unit to self-lock and issues a warning signal.

[0044] The controller monitors the oil pressure, oil temperature, and flow rate in real time via the fourth pressure sensor, the fourth temperature sensor, and the fifth flow rate sensor. When any one of the oil pressure, oil temperature, and flow rate exceeds a set threshold, the controller triggers the attachment rotation hydraulic unit to self-lock and issues a warning signal.

[0045] The controller monitors the oil temperature at the oil inlet and outlet of the cooler in real time via the second temperature differential switch. When the oil temperature at the oil inlet of the cooler is within the set temperature range, the cooler does not operate. When the oil temperature at the oil inlet of the cooler is higher than the set temperature, the controller controls the cooler to operate. When the oil temperature at the oil inlet and / or outlet of the cooler exceeds the set temperature, or when the oil temperature difference between the oil inlet and outlet of the cooler deviates from the set temperature range, the controller triggers the hydraulic oil return unit to self-lock and issues a warning signal.

[0046] The controller monitors the oil pressure difference between the oil inlet and outlet of the filter in real time through the pressure differential switch; when the oil pressure difference does not exceed the set oil pressure, the electromagnetic reversing valve is activated to connect the return oil pipeline with the fifth return oil branch; when the oil pressure difference exceeds the set oil pressure, the electromagnetic reversing valve is activated to connect the return oil pipeline with the sixth return oil branch.

[0047] The beneficial technical effects of the present invention are:

[0048] 1. The integrated hydraulic transmission system for a skid loader of the present invention is innovatively designed by the applicant's R&D team for a skid loader. Through modular design, it integrates various hydraulic system modules to make the hydraulic transmission system efficient and energy-saving, compact and flexible, precisely controllable, reliable and durable, so as to achieve a good match between the hydraulic transmission system and the hydraulic terminal. It is suitable for engineering machinery such as skid loaders that have high requirements for space, energy efficiency and versatility, and meets the compact design requirements of skid loaders to the greatest extent.

[0049] 2. The intelligent monitoring and control method of the hydraulic transmission system of the present invention performs intelligent monitoring of the hydraulic transmission system and can automatically self-lock and warn when the hydraulic transmission system operates abnormally, thereby improving the intelligence level of the hydraulic transmission system of the skid loader and enhancing operation safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 This is a schematic structural diagram of an integrated hydraulic transmission system for a skid steer loader according to an embodiment of the present invention;

[0051] Figure 2 This is a structural diagram of a hydraulic supply unit according to an embodiment of the present invention;

[0052] Figure 3 This is a structural diagram of the boom swing hydraulic unit according to an embodiment of the present invention;

[0053] Figure 4 This is a schematic structural diagram of a boom telescopic hydraulic unit according to an embodiment of the present invention;

[0054] Figure 5 This is a structural diagram of a turning hydraulic unit for an attachment according to an embodiment of the present invention;

[0055] Figure 6 This is a structural diagram of a rotary hydraulic unit of an attachment according to an embodiment of the present invention;

[0056] Figure 7 This is a schematic structural diagram of a hydraulic oil return unit according to an embodiment of the present invention;

[0057] Figure 8 is a perspective view of a skid steer loader according to an embodiment of the present invention;

[0058] Figure 9 This is a front view of a skid steer loader according to an embodiment of the present invention. DETAILED DESCRIPTION

[0059] To make the objectives, technical solutions, and beneficial effects of the present invention more clearly understood, the present invention is further described below in conjunction with specific embodiments and with reference to the accompanying drawings. Certain embodiments of the present invention will be more fully described below with reference to the accompanying drawings, some, but not all, of which are illustrated. The various embodiments of the present invention may be implemented in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present invention satisfies applicable legal requirements.

[0060] In the description of the present invention, it should be noted that the terms "inner," "outer," "upper," "lower," "front," and "rear," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0061] Please refer to Figures 1 to 9 As shown, in an embodiment of the present invention, an integrated hydraulic transmission system and an intelligent monitoring and control method for a skid loader are provided.

[0062] An integrated hydraulic transmission system for a skid loader includes a hydraulic supply unit a, an arm swing hydraulic unit b, an arm telescopic hydraulic unit c, an attachment flip hydraulic unit d, an attachment rotation hydraulic unit e, a hydraulic oil return unit f, and an oil tank g.

[0063] The boom swing hydraulic unit b, the boom telescopic hydraulic unit c, the attachment flip hydraulic unit d and the attachment rotation hydraulic unit e are connected in parallel, and the hydraulic supply unit a is used to supply hydraulic oil to the boom swing hydraulic unit b, the boom telescopic hydraulic unit c, the attachment flip hydraulic unit d and the attachment rotation hydraulic unit e.

[0064] The boom swing hydraulic unit b includes a swing hydraulic cylinder 21 , and is used to drive the two parallel swing hydraulic cylinders 21 to extend and retract, thereby driving the main boom 82 to swing up and down relative to the vehicle chassis 81 .

[0065] The boom telescopic hydraulic unit c includes a telescopic hydraulic cylinder 31 , and is used to drive the two parallel telescopic hydraulic cylinders 31 to telescope, thereby driving the telescopic boom 83 to move forward and backward relative to the main boom 82 .

[0066] The attachment turning hydraulic unit d includes a turning hydraulic cylinder 41 , and is used to drive the two parallel turning hydraulic cylinders 41 to extend and retract, thereby driving the attachment support seat 84 to swing up and down relative to the end of the telescopic arm 83 .

[0067] The attachment rotation hydraulic unit e includes a hydraulic motor 51, and is used to drive the output end of the hydraulic motor 51 to rotate, thereby driving the attachment 85 to rotate relative to the attachment support 84. In this embodiment, the attachment 85 is configured as a bucket.

[0068] The hydraulic oil return unit f is used to return oil to the boom swing hydraulic unit b, the boom telescopic hydraulic unit c, the attachment flip hydraulic unit d and the attachment rotation hydraulic unit e.

[0069] In a skid-steer loader, one end of the main boom 82 is articulated to the vehicle chassis 81. One end of the swing hydraulic cylinder 21 is articulated to the vehicle chassis 81, and the other end of the swing hydraulic cylinder 21 is articulated to the other end of the main boom 82. A telescopic boom 83 is nested within the main boom 82, slidingly fitting with the main boom 82 and capable of forward and backward movement relative to the main boom 82. The ends of the telescopic hydraulic cylinder 31 are connected to the main boom 82 and the telescopic boom 83, respectively. The distal end of the telescopic boom 83 is bent downward, forming an overall L-shape. The lower end of the attachment support 84 is articulated to the distal end of the telescopic boom 83, and the distal ends of the tilt hydraulic cylinder 41 are articulated to the upper end of the attachment support 84 and the telescopic boom 83, respectively. The attachment 85 is rotationally connected to the attachment support 84 via a rotating support 851. A hydraulic motor 51 is mounted on the attachment support 84, and the output end of the hydraulic motor 51 is connected to the attachment 85. The attachment 85 is provided with a ring gear, which is coaxially arranged with the rotating support 851. The output end of the hydraulic motor 51 is connected to a drive gear, which meshes with the ring gear. The output end of the hydraulic motor 51 drives the drive gear to rotate, which in turn meshes with the ring gear, driving the attachment 85 to rotate relative to the attachment support base 84.

[0070] In this embodiment of the skid-steer loader, the boom swing hydraulic unit b drives the swing cylinder 21 to extend and retract, causing the main boom 82 to swing up and down relative to the vehicle chassis 81, thereby driving the attachment 85 to swing up and down significantly. The boom extension hydraulic unit c drives the extension and retraction hydraulic cylinder 31 to extend and retract, driving the telescopic boom 83 to move forward and backward relative to the main boom 82, thereby driving the attachment 85 to move forward and backward. The attachment tilt hydraulic unit d drives the tilt hydraulic cylinder 41 to extend and retract, causing the attachment support 84 to swing up and down relative to the end of the telescopic boom 83, thereby driving the attachment 85 to swing up and down slightly. The attachment rotation hydraulic unit e drives the output end of the hydraulic motor 51 to rotate, causing the attachment 85 to rotate relative to the attachment support 84, thereby causing the attachment 85 to assume different angles relative to the horizontal, allowing the attachment 85 to adapt to different objects. This improves the skid-steer loader's operating range and operational freedom.

[0071] The hydraulic supply unit a includes a hydraulic pump 11, an oil inlet pipeline 12 and an oil outlet pipeline 13; the oil inlet end of the hydraulic pump 11 is connected to the oil tank g via the oil inlet pipeline 12, the oil outlet end of the hydraulic pump 11 is connected to one end of the oil outlet pipeline 13, and the oil outlet pipeline 13 is connected to the oil tank g via the first oil return pipeline 14. A proportional overflow valve 15 is provided on the first oil return pipeline 14.

[0072] The hydraulic pump 11 pumps the hydraulic oil in the oil tank g to the oil outlet line 13 through the oil inlet line 12, and sets the oil pressure of the oil outlet line 13 through the proportional relief valve 15. When the oil pressure exceeds the set threshold, it flows back to the oil tank g through the first return oil line 14.

[0073] The arm swing hydraulic unit b also includes a first proportional directional valve 22, a first solenoid valve 23, a first check valve 24 and a first accumulator 25; the rodless chamber oil port and the rod chamber oil port of the swing hydraulic cylinder 21 are respectively connected to the A1 port and B1 port of the first proportional directional valve 22, and the P1 port and T1 port of the first proportional directional valve 22 are respectively connected to the A2 port and B2 port of the first solenoid valve 23, and the P2 port of the first solenoid valve 23 is connected to the other end of the oil outlet pipeline 13 via the first oil outlet branch 26. A first check valve 24 is provided on the first oil outlet branch 26. The first accumulator 25 is connected between the P2 port of the first solenoid valve 23 and the first check valve 24 on the first oil outlet branch 26, and the T2 port of the first solenoid valve 23 is connected to the hydraulic oil return unit f.

[0074] The first solenoid valve 23 switches to the working position, connecting port P2 with port A2 and port T2 with port B2. With the first solenoid valve 23 switched to the working position, the first proportional directional valve 22 switches to the first working position, connecting port P1 with port A1 and port T1 with port B1. The hydraulic oil in the oil outlet line 13 is delivered to the rodless chamber of the swing hydraulic cylinder 21, driving the swing hydraulic cylinder 21 to extend. The hydraulic oil in the rodless chamber of the swing hydraulic cylinder 21 flows back through the hydraulic return unit f to the oil tank g. With the first solenoid valve 23 switched to the working position, the first proportional directional valve 22 switches to the second working position, connecting port P1 with port B1 and port T1 with port A1. The hydraulic oil in the oil outlet line 13 is delivered to the rodless chamber of the swing hydraulic cylinder 21, driving the swing hydraulic cylinder 21 to retract. The hydraulic oil in the rodless chamber of the swing hydraulic cylinder 21 flows back through the hydraulic return unit f to the oil tank g.

[0075] The first solenoid valve 23 switches to the closed position, disconnecting ports P2 from A2 and T2 from B2. Hydraulic oil from the first oil outlet branch 26 enters the first accumulator 25 for storage. The first solenoid valve 23 switches back to the working position, where the first accumulator 25 stores hydraulic oil, and the auxiliary oil outlet line 13 supplies hydraulic oil again. In this way, when the first solenoid valve 23 switches between the working and closed positions, the first accumulator 25 "smooths" the oil pressure, preventing hydraulic shock fluctuations caused by the oil supply from the oil outlet line 13 on the boom swing hydraulic unit b.

[0076] The arm telescopic hydraulic unit c also includes a second proportional directional valve 32, a second solenoid valve 33, a second one-way valve 34 and a second accumulator 35; the rodless chamber oil port and the rod chamber oil port of the telescopic hydraulic cylinder 31 are respectively connected to the A2 port and B2 port of the second proportional directional valve 32, and the P2 port and T2 port of the second proportional directional valve 32 are respectively connected to the A3 port and B3 port of the second solenoid valve 33, and the P3 port of the second solenoid valve 33 is connected to the other end of the oil outlet pipeline 13 via a second oil outlet branch 36. A second one-way valve 34 is provided on the second oil outlet branch 36. The second accumulator 35 is connected between the P3 port of the second solenoid valve 33 and the second one-way valve 34 on the second oil outlet branch 36, and the T3 port of the second solenoid valve 33 is connected to the hydraulic oil return unit f.

[0077] The second solenoid valve 33 switches to the working position, connecting port P3 with port A3 and port T3 with port B3. Upon switching to the working position, the second proportional directional valve 32 switches to the first working position, connecting port P2 with port A2 and port T2 with port B2. Hydraulic oil in the oil outlet line 13 is delivered to the rodless chamber of the telescopic hydraulic cylinder 31, driving the telescopic hydraulic cylinder 31 to extend. The hydraulic oil in the rodless chamber of the telescopic hydraulic cylinder 31 flows back through the hydraulic return unit f to the oil tank g. Upon switching to the working position, the second proportional directional valve 32 switches to the second working position, connecting port P2 with port B2 and port T2 with port A2. Hydraulic oil in the oil outlet line 13 is delivered to the rodless chamber of the telescopic hydraulic cylinder 31, driving the telescopic hydraulic cylinder 31 to retract. The hydraulic oil in the rodless chamber of the telescopic hydraulic cylinder 31 flows back through the hydraulic return unit f to the oil tank g.

[0078] The second solenoid valve 33 switches to the closed position, disconnecting ports P3 from A3 and T3 from B3. Hydraulic oil from the second oil outlet branch 36 enters the second accumulator 35 for storage. The second solenoid valve 33 switches back to the working position, where the second accumulator 35 stores hydraulic oil, and the auxiliary oil outlet line 13 supplies hydraulic oil again. In this way, when the second solenoid valve 33 switches between the working and closed positions, the second accumulator 35 smooths out oil pressure peaks and valleys, preventing hydraulic shock fluctuations from the oil outlet line 13 on the boom telescopic hydraulic unit c.

[0079] The attachment turning hydraulic unit d also includes a third proportional directional valve 42, a third solenoid valve 43, a third one-way valve 44 and a third accumulator 45; the rodless chamber oil port and the rod chamber oil port of the turning hydraulic cylinder 41 are respectively connected to the A5 port and B5 port of the third proportional directional valve 42, and the P5 port and T5 port of the third proportional directional valve 42 are respectively connected to the A6 port and B6 port of the third solenoid valve 43, and the P6 port of the third solenoid valve 43 is connected to the other end of the oil outlet pipeline 13 via the third oil outlet branch 46. A third one-way valve 44 is provided on the third oil outlet branch 46. The third accumulator 45 is connected between the P6 port of the third solenoid valve 43 and the third one-way valve 44 on the third oil outlet branch 46, and the T6 port of the third solenoid valve 43 is connected to the hydraulic return oil unit f.

[0080] The third solenoid valve 43 switches to the working position, connecting port P6 with port A6 and port T6 with port B6. Upon switching to the working position, the third proportional directional valve 42 switches to the first working position, connecting port P5 with port A5 and port T5 with port B5. Hydraulic oil in the oil outlet line 13 is delivered to the rodless chamber of the tilt hydraulic cylinder 41, causing the tilt hydraulic cylinder 41 to extend. The hydraulic oil in the rodless chamber of the tilt hydraulic cylinder 41 flows back through the hydraulic return unit f to the oil tank g. Upon switching to the working position, the third proportional directional valve 42 switches to the second working position, connecting port P5 with port B5 and port T5 with port A5. Hydraulic oil in the oil outlet line 13 is delivered to the rodless chamber of the tilt hydraulic cylinder 41, causing the tilt hydraulic cylinder 41 to retract. The hydraulic oil in the rodless chamber of the tilt hydraulic cylinder 41 flows back through the hydraulic return unit f to the oil tank g.

[0081] The third solenoid valve 43 switches to the closed position, disconnecting ports P6 from A6 and T6 from B6. The hydraulic oil in the third oil outlet branch 46 enters the third accumulator 45 for storage. The third solenoid valve 43 switches back to the active position, where the third accumulator 45 stores hydraulic oil, and the auxiliary oil outlet line 13 supplies hydraulic oil again. Thus, when the third solenoid valve 43 switches between the active and closed positions, the third accumulator 45 smooths out the oil pressure peaks and valleys, preventing hydraulic shock and fluctuations caused by the oil supply from the outlet line 13 to the attachment tilting hydraulic unit d.

[0082] The attachment rotation hydraulic unit e also includes a fourth proportional directional valve 52, a fourth solenoid valve 53, a fourth check valve 54 and a fourth accumulator 55; the two oil ports of the hydraulic motor 51 are respectively connected to the A7 port and B7 port of the fourth proportional directional valve 52, the P7 port and T7 port of the fourth proportional directional valve 52 are respectively connected to the A8 port and B8 port of the fourth solenoid valve 53, the T8 port of the fourth solenoid valve 53 is connected to the other end of the oil outlet pipeline 13 via the fourth oil outlet branch 56, a fourth check valve 54 is provided on the fourth oil outlet branch 56, and the fourth accumulator 55 is connected between the T8 port of the fourth solenoid valve 53 and the fourth check valve 54 on the fourth oil outlet branch 56, and the P8 port of the fourth solenoid valve 53 is connected to the hydraulic oil return unit f.

[0083] The fourth solenoid valve 53 switches to the working position, connecting port P8 with port A8 and port T8 with port B8. Upon switching the fourth solenoid valve 53 to the working position, the fourth proportional directional valve 52 switches to the first working position, connecting port P7 with port A7 and port T7 with port B7, and the hydraulic oil drives the hydraulic motor 51 in the forward direction. Upon switching the fourth solenoid valve 53 to the working position, the fourth proportional directional valve 52 switches to the second working position, connecting port P7 with port B7 and port T7 with port A7, and the hydraulic oil drives the hydraulic motor 51 in the reverse direction.

[0084] The fourth solenoid valve 53 switches to the closed position, disconnecting ports P8 from A8 and T8 from B8. The hydraulic oil in the fourth oil outlet branch 56 enters the fourth accumulator 55 for storage. The fourth solenoid valve 53 switches back to the active position, where the fourth accumulator 55 stores hydraulic oil, and the auxiliary oil outlet line 13 supplies hydraulic oil again. This way, when the fourth solenoid valve 53 switches between the active and closed positions, the fourth accumulator 55 smooths out the oil pressure peaks and valleys, preventing hydraulic shock and fluctuations caused by the oil supply from the outlet line 13 to the attachment rotation hydraulic unit e.

[0085] Two hydraulic return units f are provided, each comprising a manifold valve 61 and a return line 62. Port T2 of the first solenoid valve 23 is connected to the oil inlet of the manifold valve 61 of the first hydraulic return unit f via a first return line branch, which is equipped with a fifth check valve. Port T3 of the second solenoid valve 33 is connected to the oil inlet of the manifold valve 61 of the first hydraulic return unit f via a second return line branch, which is equipped with a sixth check valve. Port T6 of the third solenoid valve 43 is connected to the oil inlet of the manifold valve 61 of the second hydraulic return unit f via a third return line branch, which is equipped with a seventh check valve. Port P8 of the fourth solenoid valve 53 is connected to the oil inlet of the manifold valve 61 of the second hydraulic return unit f via a fourth return line branch, which is equipped with an eighth check valve. The oil outlet of each manifold valve 61 of the hydraulic return unit f is connected to the fuel tank g via a return line 62.

[0086] In the hydraulic transmission system described above, a heater 711 is installed on the oil inlet pipeline 12. A first temperature differential switch 712 is connected to the oil inlet and outlet of the heater 711. A first flow sensor 713 is installed on the oil outlet pipeline 13. A first pressure sensor 721, a first temperature sensor 722, and a second flow sensor 723 are connected to the pipeline between the rodless chamber oil port of the swing hydraulic cylinder 21 and port A1 of the first proportional directional valve 22. A second pressure sensor 731, a second temperature sensor 732, and a third flow sensor 733 are connected to the pipeline between the rodless chamber oil port of the telescopic hydraulic cylinder 31 and port A2 of the second proportional directional valve 32. A third pressure sensor 741, a third temperature sensor 742, and a fourth flow sensor 743 are connected to the pipeline between the rodless chamber oil port of the tilt hydraulic cylinder 41 and port B5 of the third proportional directional valve 42. A fourth pressure sensor 751, a fourth temperature sensor 752, and a fifth flow sensor 753 are connected to the pipeline between one oil port of the hydraulic motor 51 and port B7 of the fourth proportional directional valve 52. A cooler 761 is provided on the oil return line 62, and a second temperature differential switch 762 is connected to the oil inlet and oil outlet of the cooler 761. The oil return line 62 is connected to the oil inlet of the solenoid reversing valve 763, and the two oil outlets of the solenoid reversing valve 763 are connected to the oil tank g via the fifth and sixth oil return branches, respectively. A filter 764 is provided on the fifth oil return branch, and a pressure differential switch 765 is connected to the oil inlet and oil outlet of the filter 764.

[0087] The controller respectively signals the heater 711, the first temperature differential switch 712, the first flow sensor 713, the first pressure sensor 721, the first temperature sensor 722, the second flow sensor 723, the second pressure sensor 731, the second temperature sensor 732, the third flow sensor 733, the third pressure sensor 741, the third temperature sensor 742, the fourth flow sensor 743, the fourth pressure sensor 751, the fourth temperature sensor 752, the fifth flow sensor 753, the cooler 761, the second temperature differential switch 762, the electromagnetic reversing valve 763 and the pressure differential switch 765.

[0088] A method for intelligent monitoring and control of a hydraulic transmission system is provided for monitoring and controlling the above-mentioned integrated hydraulic transmission system of a skid loader. The method operates as follows:

[0089] The controller monitors the oil temperature of the oil inlet and oil outlet of the heater 711 in real time through the first temperature difference switch 712, and monitors the flow rate in real time through the first flow sensor 713; when the oil temperature of the oil inlet of the heater 711 is within the set temperature range, the heater 711 does not operate; when the oil temperature of the oil inlet of the heater 711 is lower than the set temperature, the controller controls the heater 711 to operate to heat the hydraulic oil and improve the hydraulic characteristics of the hydraulic oil; when the oil temperature of the oil inlet and / or oil outlet of the heater 711 exceeds the set temperature, or when the oil temperature difference between the oil inlet and oil outlet of the heater 711 deviates from the set temperature range, or when the flow rate exceeds the set threshold, the controller triggers the hydraulic supply unit a to self-lock and sends a warning signal.

[0090] The controller monitors the oil pressure, oil temperature and flow in real time through the first pressure sensor 721, the first temperature sensor 722 and the second flow sensor 723. When any one of the oil pressure, oil temperature and flow exceeds the set threshold, the controller triggers the arm swing hydraulic unit b to self-lock and issues a warning signal.

[0091] The controller monitors the oil pressure, oil temperature and flow in real time through the second pressure sensor 731, the second temperature sensor 732 and the third flow sensor 733. When any one of the oil pressure, oil temperature and flow exceeds the set threshold, the controller triggers the boom telescopic hydraulic unit c to self-lock and issues a warning signal.

[0092] The controller monitors the oil pressure, oil temperature and flow in real time through the third pressure sensor 741, the third temperature sensor 742 and the fourth flow sensor 743. When any one of the oil pressure, oil temperature and flow exceeds the set threshold, the controller triggers the attachment flip hydraulic unit d to self-lock and issues a warning signal.

[0093] The controller monitors the oil pressure, oil temperature and flow in real time through the fourth pressure sensor 751, the fourth temperature sensor 752 and the fifth flow sensor 753. When any one of the oil pressure, oil temperature and flow exceeds the set threshold, the controller triggers the attachment rotation hydraulic unit e to self-lock and issues a warning signal.

[0094] The controller monitors the oil temperature of the oil inlet and oil outlet of the cooler 761 in real time via the second temperature difference switch 762; when the oil temperature of the oil inlet of the cooler 761 is within the set temperature range, the cooler 761 does not operate; when the oil temperature of the oil inlet of the cooler 761 is higher than the set temperature, the controller controls the cooler 761 to operate so as to cool the hydraulic oil returning to the oil tank g; when the oil temperature of the oil inlet and / or oil outlet of the cooler 761 exceeds the set temperature, or when the oil temperature difference between the oil inlet and oil outlet of the cooler 761 deviates from the set temperature range, the controller triggers the self-locking of the hydraulic oil return unit f and issues a warning signal;

[0095] The controller monitors the oil pressure difference between the oil inlet and the oil outlet of the filter 764 in real time through the pressure differential switch 765; when the oil pressure difference does not exceed the set oil pressure, the electromagnetic reversing valve 763 is actuated to connect the return oil pipeline 62 with the fifth return oil branch; when the oil pressure difference exceeds the set oil pressure, it is determined that the filter 764 is blocked, and the electromagnetic reversing valve 763 is actuated to connect the return oil pipeline 62 with the sixth return oil branch.

[0096] So far, the present embodiment has been described in detail in conjunction with the accompanying drawings. Based on the above description, those skilled in the art should have a clear understanding of the integrated hydraulic transmission system and intelligent monitoring and control method for a skid loader of the present invention. The integrated hydraulic transmission system for a skid loader of the present invention is aimed at a skid loader innovatively designed by the applicant's research and development team. Through modular design, it integrates the hydraulic system modules of various parts to make the hydraulic transmission system efficient and energy-saving, compact and flexible, precisely controllable, reliable and durable, so as to achieve a good match between the hydraulic transmission system and the hydraulic terminal. It is suitable for engineering machinery such as skid loaders that have high requirements for space, energy efficiency and versatility, and meets the compact design requirements of skid loaders to the greatest extent. The intelligent monitoring and control method for the hydraulic transmission system of the present invention performs intelligent monitoring of the hydraulic transmission system, and can automatically self-lock and warn when the hydraulic transmission system is working abnormally, thereby improving the intelligence level of the hydraulic transmission system of the skid loader and improving operational safety.

[0097] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An integrated hydraulic transmission system for a skid loader, characterized in that: include: A hydraulic supply unit is used to supply hydraulic oil to the boom swing hydraulic unit, boom telescopic hydraulic unit, attachment flip hydraulic unit, and attachment rotation hydraulic unit connected in parallel; The boom swing hydraulic unit includes a swing hydraulic cylinder. The boom swing hydraulic unit is used to drive the swing hydraulic cylinder to extend and retract, thereby driving the main boom to swing up and down relative to the vehicle chassis; The boom telescopic hydraulic unit includes a telescopic hydraulic cylinder, which is used to drive the telescopic hydraulic cylinder to extend and retract, thereby driving the telescopic boom to move forward and backward relative to the main boom; The attachment turning hydraulic unit includes a turning hydraulic cylinder, which is used to drive the turning hydraulic cylinder to extend and retract, thereby driving the attachment support base to swing up and down relative to the end of the telescopic boom; An attachment rotation hydraulic unit includes a hydraulic motor, the attachment rotation hydraulic unit is used to drive the output end of the hydraulic motor to rotate, thereby driving the attachment to rotate relative to the attachment support base; Hydraulic oil return unit, used to return oil to the boom swing hydraulic unit, boom telescopic hydraulic unit, attachment flip hydraulic unit, and attachment rotation hydraulic unit; One end of the main boom is articulated to the vehicle chassis, one end of the swing hydraulic cylinder is articulated to the vehicle chassis, and the other end of the swing hydraulic cylinder is articulated to the other end of the main boom; The telescopic boom is slidably matched with the main boom, and the telescopic boom can move forward and backward relative to the main boom, and the two ends of the telescopic hydraulic cylinder are respectively connected to the main boom and the telescopic boom; The lower end of the attachment support base is hinged to the end of the telescopic boom, and the two ends of the tilting hydraulic cylinder are hinged to the upper end of the attachment support base and the telescopic boom respectively; The attachment is rotatably connected to the attachment support base, the hydraulic motor is arranged on the attachment support base, and the output end power of the hydraulic motor is connected to the attachment.

2. The integrated hydraulic transmission system for a skid steer loader according to claim 1, characterized in that: The hydraulic supply unit includes a hydraulic pump, an oil inlet pipeline and an oil outlet pipeline; The oil inlet end of the hydraulic pump is connected to the oil tank via an oil inlet pipeline, the oil outlet end of the hydraulic pump is connected to one end of an oil outlet pipeline, and the oil outlet pipeline is connected to the oil tank via a first oil return pipeline. A proportional overflow valve is provided on the first oil return pipeline.

3. The integrated hydraulic transmission system for a skid steer loader according to claim 2, characterized in that: The boom swing hydraulic unit also includes a first proportional directional valve, a first solenoid valve, a first one-way valve and a first accumulator; The rodless chamber oil port and the rod chamber oil port of the swing hydraulic cylinder are respectively connected to the A1 port and B1 port of the first proportional directional valve, the P1 port and T1 port of the first proportional directional valve are respectively connected to the A2 port and B2 port of the first solenoid valve, the P2 port of the first solenoid valve is connected to the other end of the oil outlet pipeline via the first oil outlet branch, a first check valve is arranged on the first oil outlet branch, a first accumulator is connected between the P2 port of the first solenoid valve and the first check valve on the first oil outlet branch, and the T2 port of the first solenoid valve is connected to the hydraulic oil return unit.

4. The integrated hydraulic transmission system for a skid steer loader according to claim 3, characterized in that: The boom telescopic hydraulic unit also includes a second proportional directional valve, a second solenoid valve, a second one-way valve and a second accumulator; The rodless chamber oil port and the rod chamber oil port of the telescopic hydraulic cylinder are respectively connected to the A2 port and B2 port of the second proportional directional valve, the P2 port and T2 port of the second proportional directional valve are respectively connected to the A3 port and B3 port of the second solenoid valve, the P3 port of the second solenoid valve is connected to the other end of the oil outlet pipeline via the second oil outlet branch, a second one-way valve is arranged on the second oil outlet branch, a second accumulator is connected between the P3 port of the second solenoid valve and the second one-way valve on the second oil outlet branch, and the T3 port of the second solenoid valve is connected to the hydraulic oil return unit.

5. The integrated hydraulic transmission system for a skid steer loader according to claim 4, characterized in that: The attachment turning hydraulic unit also includes a third proportional directional valve, a third solenoid valve, a third one-way valve and a third accumulator; The rodless chamber oil port and the rod chamber oil port of the flip hydraulic cylinder are respectively connected to the A5 port and B5 port of the third proportional directional valve, the P5 port and T5 port of the third proportional directional valve are respectively connected to the A6 port and B6 port of the third solenoid valve, the P6 port of the third solenoid valve is connected to the other end of the oil outlet pipeline via the third oil outlet branch, a third check valve is arranged on the third oil outlet branch, a third accumulator is connected between the P6 port of the third solenoid valve and the third check valve on the third oil outlet branch, and the T6 port of the third solenoid valve is connected to the hydraulic oil return unit.

6. The integrated hydraulic transmission system for a skid steer loader according to claim 5, characterized in that: The attachment rotation hydraulic unit also includes a fourth proportional directional valve, a fourth solenoid valve, a fourth one-way valve and a fourth accumulator; The two oil ports of the hydraulic motor are respectively connected to the A7 port and B7 port of the fourth proportional directional valve, the P7 port and T7 port of the fourth proportional directional valve are respectively connected to the A8 port and B8 port of the fourth solenoid valve, the T8 port of the fourth solenoid valve is connected to the other end of the oil outlet pipeline via the fourth oil outlet branch, a fourth check valve is arranged on the fourth oil outlet branch, the fourth accumulator is connected between the T8 port of the fourth solenoid valve and the fourth check valve on the fourth oil outlet branch, and the P8 port of the fourth solenoid valve is connected to the hydraulic oil return unit.

7. The integrated hydraulic transmission system for a skid steer loader according to claim 6, characterized in that: The hydraulic oil return unit includes a collecting valve and an oil return pipeline; The T2 port of the first solenoid valve is connected to the oil inlet of the collecting valve via the first oil return branch, the T3 port of the second solenoid valve is connected to the oil inlet of the collecting valve via the second oil return branch, the T6 port of the third solenoid valve is connected to the oil inlet of the collecting valve via the third oil return branch, the P8 port of the fourth solenoid valve is connected to the oil inlet of the collecting valve via the fourth oil return branch, and the oil outlet of the collecting valve is connected to the oil tank via the oil return pipeline.

8. The integrated hydraulic transmission system for a skid steer loader according to claim 7, characterized in that: A heater is provided on the oil inlet pipeline, a first temperature difference switch is connected to the oil inlet and the oil outlet of the heater, and a first flow sensor is provided on the oil outlet pipeline; The pipeline between the rodless chamber oil port of the swing hydraulic cylinder and the A1 port of the first proportional directional valve is connected with a first pressure sensor, a first temperature sensor and a second flow sensor; The pipeline between the rodless chamber oil port of the telescopic hydraulic cylinder and the A2 port of the second proportional directional valve is connected with a second pressure sensor, a second temperature sensor and a third flow sensor; The pipeline between the rod chamber oil port of the tilting hydraulic cylinder and the B5 port of the third proportional directional valve is connected to a third pressure sensor, a third temperature sensor and a fourth flow sensor; A fourth pressure sensor, a fourth temperature sensor, and a fifth flow sensor are connected to the pipeline between an oil port of the hydraulic motor and the B7 port of the fourth proportional directional valve; A cooler is provided on the oil return pipeline, and a second temperature difference switch is connected to the oil inlet and the oil outlet of the cooler; The oil return line is connected to the oil inlet of the electromagnetic reversing valve, and the two oil outlets of the electromagnetic reversing valve are connected to the oil tank through the fifth oil return branch and the sixth oil return branch respectively. A filter is provided on the fifth oil return branch, and the differential pressure switch is connected to the oil inlet and oil outlet of the filter; The controller respectively connects the heater, the first temperature differential switch, the first flow sensor, the first pressure sensor, the first temperature sensor, the second flow sensor, the second pressure sensor, the second temperature sensor, the third flow sensor, the third pressure sensor, the third temperature sensor, the fourth flow sensor, the fourth pressure sensor, the fourth temperature sensor, the fifth flow sensor, the cooler, the second temperature differential switch, the electromagnetic reversing valve and the pressure differential switch.

9. A method for intelligent monitoring and control of a hydraulic transmission system, for monitoring and controlling the integrated hydraulic transmission system of a skid loader according to claim 8, characterized in that: The method operates as follows: The controller monitors the oil temperature at the oil inlet and oil outlet of the heater in real time via the first temperature differential switch, and monitors the flow rate in real time via the first flow sensor; when the oil temperature at the oil inlet of the heater is within a set temperature range, the heater does not operate; when the oil temperature at the oil inlet of the heater is lower than the set temperature, the controller controls the heater to operate; when the oil temperature at the oil inlet and / or oil outlet of the heater exceeds the set temperature, or when the oil temperature difference between the oil inlet and oil outlet of the heater deviates from the set temperature range, or when the flow rate exceeds a set threshold, the controller triggers the hydraulic supply unit to self-lock and issues a warning signal; The controller monitors the oil pressure, oil temperature and flow rate in real time via the first pressure sensor, the first temperature sensor and the second flow rate sensor. When any one of the oil pressure, oil temperature and flow rate exceeds the set threshold, the controller triggers the boom swing hydraulic unit to self-lock and issues a warning signal. The controller monitors the oil pressure, oil temperature and flow rate in real time via the second pressure sensor, the second temperature sensor and the third flow rate sensor. When any one of the oil pressure, oil temperature and flow rate exceeds the set threshold, the controller triggers the boom extension hydraulic unit to self-lock and issues a warning signal. The controller monitors the oil pressure, oil temperature, and flow rate in real time via the third pressure sensor, the third temperature sensor, and the fourth flow rate sensor. When any one of the oil pressure, oil temperature, and flow rate exceeds a set threshold, the controller triggers the attachment's turning hydraulic unit to self-lock and issues a warning signal. The controller monitors the oil pressure, oil temperature, and flow rate in real time via the fourth pressure sensor, the fourth temperature sensor, and the fifth flow rate sensor. When any one of the oil pressure, oil temperature, and flow rate exceeds a set threshold, the controller triggers the attachment rotation hydraulic unit to self-lock and issues a warning signal. The controller monitors the oil temperature at the oil inlet and outlet of the cooler in real time via the second temperature differential switch. When the oil temperature at the oil inlet of the cooler is within the set temperature range, the cooler does not operate. When the oil temperature at the oil inlet of the cooler is higher than the set temperature, the controller controls the cooler to operate. When the oil temperature at the oil inlet and / or outlet of the cooler exceeds the set temperature, or when the oil temperature difference between the oil inlet and outlet of the cooler deviates from the set temperature range, the controller triggers the hydraulic oil return unit to self-lock and issues a warning signal. The controller monitors the oil pressure difference between the oil inlet and outlet of the filter in real time through the pressure differential switch; when the oil pressure difference does not exceed the set oil pressure, the electromagnetic reversing valve is activated to connect the return oil pipeline with the fifth return oil branch; when the oil pressure difference exceeds the set oil pressure, the electromagnetic reversing valve is activated to connect the return oil pipeline with the sixth return oil branch.

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