Protection system and protection method for working device of crushing excavator

Abstract

The invention discloses a protection system and a protection method for a working device of a crushing excavator, and belongs to the technical field of crushing excavators. The system comprises a first overflow valve, a second overflow valve, a third overflow valve, a fourth overflow valve and a fourth overflow valve, and the first overflow valve is used for controlling overflow pressure of a rod cavity of a movable arm oil cylinder of the crushing excavator under control of control equipment; the second overflow valve is used for controlling overflow pressure of a rodless cavity of a movable arm oil cylinder of the crushing excavator under the control of the control equipment; the multi-way valve assembly is used for controlling the movement direction of a breaking hammer drill rod and lifting of a working device of the crushing excavator by changing the flow direction of hydraulic oil; the switch valve is used for detecting equipment for on-off control, and the control equipment is used for activating a crushing mode and controlling the pressing pressure of the working device by adjusting the pressure upper limit values of a rod cavity of the movable arm oil cylinder and a rodless cavity of the movable arm oil cylinder; and the display module is used for setting the crushing mode and the crushing parameters of the crushing excavator. The safety of the breaking excavator and the breaking hammer of the breaking excavator can be guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of crushing excavators, and in particular to a protection system and a protection method for a working device of a crushing excavator. Background Art

[0002] Currently, the use of explosives for crushing and blasting is prohibited in the crushing and blasting industry. A new blasting mode in which an excavator is equipped with a hydraulic breaker has become the mainstream and is widely used in fields such as building demolition, high-speed rail and airport construction, and mine exploitation.

[0003] When a traditional special crushing excavator is in the crushing operation condition, the driver manually adjusts the lifting of the hydraulic breaker according to experience and prevents the hydraulic breaker from bouncing by pressing the boom to obtain higher crushing efficiency. When encountering harder rocks, in order to enable the crushing excavator to hold down the hydraulic breaker during the crushing process for safe operation, a greater force is often required. Obviously, this will increase the interaction force between the hydraulic breaker and the rock. The pressures in the rod chamber and the non-rod chamber of the boom cylinder are prone to severe fluctuations due to the impact load of the hydraulic breaker, resulting in damage to the cylinder seals or bursting of the pipelines. If the force for pressing the hydraulic breaker is too large at this time, large pressure impacts will occur between the drill rod of the hydraulic breaker, the hydraulic breaker, and even the entire working device, increasing the risk of fracture of the drill rod and the working device and affecting the service life of the machine. Moreover, the lifting action of the hydraulic breaker is coupled with the boom control logic, and the operation flexibility is poor. Summary of the Invention

[0004] To solve some or all of the above-mentioned technical problems existing in the prior art, the present invention provides a protection system and a protection method for a working device of a crushing excavator, which can prevent excessive downward pressure by adjusting the upper limit values of the pressures in the large and small chambers of the boom cylinder to extend the service life of the machine and have better energy-saving effects on the basis of protecting the working device.

[0005] The technical solution of the present invention is as follows:

[0006] In a first aspect, a protection system for a working device of a crushing excavator is provided, including:

[0007] A first relief valve, the inlet of the first relief valve is connected to the pipeline connecting the rod chamber of the boom cylinder of the multi-way valve assembly, the outlet of the first relief valve is connected to the fuel tank, and the control oil port of the first relief valve is connected to the first control end of the control device to control the pressure in the rod chamber of the boom cylinder of the crushing excavator under the control of the control device;

[0008] A second overflow valve, the inlet port of the second overflow valve is connected to the connecting pipeline of the multi-way valve assembly connecting the rodless cavity of the boom cylinder, the return port of the second overflow valve is connected to the return port of the first overflow valve and then connected to the fuel tank, and the control oil port of the second overflow valve is connected to the second control end of the control device, so as to control the pressure of the rodless cavity of the boom cylinder of the breaker excavator under the control of the control device;

[0009] A multi-way valve assembly, one working oil port of the multi-way valve assembly is connected to the breaker of the breaker excavator, and is used to control the movement direction of the breaker rod by controlling the flow direction of the hydraulic oil. The other two working oil ports of the multi-way valve assembly are respectively connected to the rod cavity and the rodless cavity of the boom cylinder, and are used to control the telescopic movement of the boom cylinder by controlling the flow direction of the hydraulic oil, so as to control the rise or fall of the working device of the breaker excavator;

[0010] A detection device, the detection device is connected to the outlet connecting pipeline of the pilot port of the breaker spool of the multi-way valve assembly connecting the breaker foot pedal of the breaker excavator, and is used to detect the medium pressure in the connecting pipeline where the detection device is located;

[0011] A switching valve, the control end of the switching valve is connected to the third control end of the control device, the inlet port of the switching valve is connected to the connecting pipeline of the pilot pump connecting the boom pilot handle, and the outlet port of the switching valve is connected to the inlet port of the breaker foot pedal;

[0012] A control device, the control device is used to control the opening pressure or on-off of the first overflow valve, the second overflow valve and the switching valve, so that through the control device, the upper limit values of the pressure of the rod cavity and the rodless cavity of the boom cylinder can be adjusted by controlling the opening pressure of the first overflow valve and the second overflow valve, and the control device can also control the on-off of the oil inlet of the breaker foot pedal by controlling the on-off of the switching valve.

[0013] A display module, the display module is connected to the control device, and a setting page and a display interface for setting the breaker excavator to the breaker mode or setting breaker parameters are set on the display module, and controls for displaying adjustment and parameter setting are set on the setting page and the display interface, so that the breaker mode and breaker parameters of the breaker excavator can be set on the setting page and the display interface through the controls.

[0014] Further, in the above-mentioned protection system for the working device of a breaker excavator, both the first overflow valve and the second overflow valve include electro-hydraulic proportional overflow valves.

[0015] Further, in the above-mentioned protection system for the working device of a breaker excavator, the multi-way valve assembly includes:

[0016] The first reversing valve, the first working oil port of the first reversing valve serves as the first output port of the multi-way valve assembly, the second working oil port of the first reversing valve serves as the second output port of the multi-way valve assembly, the oil inlet of the first reversing valve serves as the first oil inlet of the multi-way valve assembly and is connected to the oil outlet of the first hydraulic pump, the oil outlet of the first reversing valve is connected to the connecting pipeline of the third overflow valve connecting the second reversing valve, the third working oil port of the first reversing valve is connected to the connecting pipeline of the oil inlet of the first reversing valve, the fourth working oil port of the first reversing valve is connected to the connecting pipeline of the second reversing valve connecting the third overflow valve, the first control of the first reversing valve serves as the third output port of the multi-way valve assembly and is connected to the oil outlet of the crushing foot pedal, and the second control end of the first reversing valve is blocked;

[0017] The second reversing valve, the first working oil port of the second reversing valve is connected to one end of the third overflow valve, the oil inlet of the second reversing valve serves as the second oil inlet of the multi-way valve assembly and is connected to the oil outlet of the second hydraulic pump, the second working oil port of the second reversing valve is connected to the connecting pipeline of the second oil inlet, the third working oil port of the second reversing valve serves as the fourth output port of the multi-way valve assembly and is connected to the rodless cavity of the boom cylinder, the fourth working oil port of the second reversing valve serves as the fifth output port of the multi-way valve assembly and is connected to the rodless cavity of the boom cylinder, the oil outlet of the second reversing valve is connected to the connecting pipeline of the third overflow valve connecting the second reversing valve, the first control end of the second reversing valve is connected to the oil outlet of one control valve in the boom pilot handle, and the second control end of the second reversing valve is connected to the oil outlet of the other control valve in the boom pilot handle;

[0018] Check valve;

[0019] The third overflow valve, the number of the third overflow valves and the check valves are both set to be multiple, multiple third overflow valves are correspondingly connected in parallel to multiple check valves, one ends of multiple third overflow valves are respectively correspondingly connected to the first working oil port and the second working oil port of the first reversing valve, and one ends of multiple third overflow valves are respectively correspondingly connected to the third working oil port and the fourth working oil port of the second reversing valve, and the other ends of multiple third overflow valves are all connected to the first working oil port of the second reversing valve;

[0020] The main overflow valve, one end of the main overflow valve is connected to the connecting pipeline of the oil return port of the multi-way valve assembly, and the other end of the main overflow valve is divided into two connecting pipelines and is respectively connected to the first oil inlet and the second oil inlet of the multi-way valve assembly through check valves.

[0021] Further, in the above-mentioned protection system for the working device of a crushing excavator, both the first reversing valve and the second reversing valve include three-position six-way hydraulic control reversing valves.

[0022] Further, in the above-mentioned protection system for the working device of a crushing excavator, the detection device includes any one or more of sensors or strain gauges.

[0023] Further, in the above-mentioned protection system for the working device of a crushing excavator, the display module includes a display, and the control elements include one or more of buttons, keys or switches provided on the display.

[0024] Further, in the above-mentioned protection system for the working device of a crushing excavator, a pilot relief valve is further included. One end of the pilot relief valve is connected to the fuel tank, and the other end is connected to the pipeline connecting the pilot pump to the boom pilot handle.

[0025] Further, in the above-mentioned protection system for the working device of a crushing excavator, a first hydraulic pump is further included. The suction port of the first hydraulic pump is connected to the fuel tank, and the oil outlet of the first hydraulic pump is connected to the first oil inlet of the multi-way valve assembly.

[0026] Further, in the above-mentioned protection system for the working device of a crushing excavator, a second hydraulic pump is further included. The second hydraulic pump is rigidly connected to the first hydraulic pump and the pilot pump. The suction port of the second hydraulic pump is connected to the fuel tank, and the oil outlet of the second hydraulic pump is connected to the second oil inlet of the multi-way valve assembly.

[0027] In a second aspect, a protection method applying the above-mentioned protection system for the working device of a crushing excavator is provided, including:

[0028] Controlling the on / off of the switching valve to switch the on / off of the oil circuit from the pilot pump to the crushing pedal, and activating or disabling the operation of the breaker;

[0029] Setting the corresponding upper pressure limit values and working modes for the rod chamber and the non-rod chamber of the boom cylinder according to different crushing modes of the crushing excavator;

[0030] Real-time detecting the medium pressure in the pipeline connecting the multi-way valve assembly to the crushing pedal, and feeding back the pressure signal to the control device;

[0031] According to the pressure signal and the preset parameters of the crushing mode of the excavator, dynamically adjusting the control signals of the first relief valve and the second relief valve to adjust the upper pressure limit values of the rod chamber and the non-rod chamber of the boom cylinder;

[0032] When the actual pressure in the rod chamber or the non-rod chamber of the boom cylinder reaches the corresponding upper pressure limit value, controlling the opening of the corresponding first relief valve or second relief valve, so that the breaker can drive the working device to perform a lowering or lifting action, and making the force of the working device pressing the hammer tend to be stable;

[0033] The boom oil chamber pressure and the working status information of the breaker are displayed in real time on the display module, and the parameter settings are updated according to the operation instructions, so that the breaker performs the breaking operation according to the set parameters and working modes.

[0034] The main advantages of the technical solution of the present invention are as follows:

[0035] A protection system for the working device of a breaker excavator according to the present invention controls the rise and fall of the breaker of the breaker excavator by setting a first overflow valve and a second overflow valve respectively, so that the problem of damage caused by excessive downward pressure of the breaker can be prevented by adjusting the upper limit values of the pressures of the large and small chambers of the boom cylinder, thereby extending the service life of the breaker excavator and its breaker. At the same time, through the on-off control of the on-off valve, the on-off control of whether the breaker of the breaker excavator works is realized, the usage conditions of the breaker are increased. At the same time, through the display module, it is convenient for the operator to control the breaking mode and breaking parameters of the breaker excavator through the display adjustment and parameter setting controls arranged on the display module, so that when the breaker excavator performs the breaking operation, it can be avoided that the operator blindly presses down the breaker according to experience, resulting in damage to the breaker excavator and its breaker, thereby ensuring the safety of the breaker excavator and its breaker. Description of the Drawings

[0036] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, and constitute a part of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0037] Figure 1 is a hydraulic schematic diagram of a protection system for the working device of a breaker excavator provided by an embodiment of the present invention;

[0038] Figure 2 is a schematic diagram of a multi-way valve assembly in the hydraulic schematic diagram of a protection system for the working device of a breaker excavator provided by an embodiment of the present invention;

[0039] Figure 3 is a schematic diagram of the interaction interface of the display module in a protection system for the working device of a breaker excavator provided by an embodiment of the present invention;

[0040] Figure 4 is a schematic diagram of the process of setting different breaking modes on the interaction interface of the display module in a protection system for the working device of a breaker excavator provided by an embodiment of the present invention;

[0041] Figure 5 is a schematic diagram of the process of a protection method for the working device of a breaker excavator provided by an embodiment of the present invention.

[0042] Description of the Reference Numerals:

[0043] 1. Display module; 2. Control device; 3. Multi-way valve assembly;

[0044] 3.1. Third overflow valve; 3.2. Check valve; 3.3. First reversing valve; 3.4. Second reversing valve; 3.5. Main overflow valve;

[0045] 4. First overflow valve; 5. Boom cylinder; 6. Second overflow valve; 7. Detection device; 8. Breaker foot pedal; 9. Boom pilot handle; 10. Switch valve; 11. Pilot overflow valve; 12. Pilot pump; 13. Second hydraulic pump; 14. First hydraulic pump; 15. Fuel tank; 16. Breaker. Specific embodiments

[0046] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0047] The following combines the attached Figures 1-5 , and details the technical solutions provided by the embodiments of the present invention.

[0048] As shown in the attached Figure 1 and Figure 2 , the embodiments of the present invention provide a protection system for the working device of a breaker excavator. The protection system includes: a first overflow valve 4, a second overflow valve 6, a multi-way valve assembly 3, a detection device 7, a switch valve 10, a control device 2, and a display module 1, wherein:

[0049] The inlet port of the first relief valve 4 is connected to the connecting pipeline of the multi-way valve assembly 3 that connects to the rod chamber of the boom cylinder 5. The return port of the first relief valve 4 is connected to the fuel tank 15. The control oil port of the first relief valve 4 is connected to the first control end of the control device 2 to control the pressure in the rod chamber of the boom cylinder 5 of the breaker excavator under the control of the control device 2. The inlet port of the second relief valve 6 is connected to the connecting pipeline of the multi-way valve assembly 3 that connects to the rodless chamber of the boom cylinder 5. The return port of the second relief valve 6 is connected to the return port of the first relief valve 4 and then to the fuel tank 15. The control oil port of the second relief valve 6 is connected to the second control end of the control device 2 to control the pressure in the rodless chamber of the boom cylinder 5 of the breaker excavator under the control of the control device 2. One working oil port of the multi-way valve assembly 3 is connected to the breaker 16 of the breaker excavator to control the movement direction of the breaker rod by controlling the flow direction of the hydraulic oil. The other two working oil ports of the multi-way valve assembly 3 are respectively connected to the rod chamber and the rodless chamber of the boom cylinder 5 to control the telescopic movement of the boom cylinder 5 by controlling the flow direction of the hydraulic oil, thereby controlling the rise or fall of the working device of the breaker excavator. The detection device 7 is connected to the outlet pipeline of the breaker pilot valve core of the multi-way valve assembly that connects to the breaker pedal 8 of the breaker excavator to detect the medium pressure in the connecting pipeline where the detection device 7 is located. The control end of the switch valve 10 is connected to the third control end of the control device 2. The inlet port of the switch valve 10 is connected to the connecting pipeline of the pilot pump 12 that connects to the boom pilot handle 9. The outlet port of the switch valve 10 is connected to the inlet port of the breaker pedal 8. The control device 2 is used to control the opening pressure or on / off of the first relief valve 4, the second relief valve 6, and the switch valve 10, so that the control device 2 can adjust the upper limit values of the pressure in the rod chamber of the boom cylinder 5 and the rodless chamber of the boom cylinder 5 by controlling the opening pressure of the first relief valve 4, the second relief valve 6, and the switch valve 10, and the control device 2 can also control the on / off of the inlet of the breaker pedal by controlling the on / off of the switch valve 10. The display module 1 is connected to the control device 2. A setting page and a display interface for setting the breaker excavator to the breaker mode or setting breaker parameters are provided on the display module 1, and controls for displaying adjustment and parameter setting are provided on the setting page and the display interface, so that the breaker mode and breaker parameters of the breaker excavator can be set on the setting page and the display interface through the controls.

[0050] A protection system for the working device of a crushing excavator according to the present invention controls the rise and fall of the breaker of the crushing excavator through the first overflow valve 4 and the second overflow valve 6 respectively, so that the problem of damage caused by excessive downward pressure of the breaker 16 can be prevented by adjusting the upper limit values of the pressures of the large and small chambers of the boom cylinder 5, thereby extending the service life of the crushing excavator and its breaker 16. At the same time, through the on-off control of the switching valve 10, the on-off control of whether the breaker 16 of the crushing excavator works is realized, increasing the operating conditions of the breaker. At the same time, through the display module 1, it is convenient for the operator to control the crushing mode and crushing parameters of the crushing excavator through the display adjustment and parameter setting controls arranged on the display module, so that when the crushing excavator is performing crushing operations, it is possible to avoid the operator blindly pressing down the breaker 16 according to experience, causing damage to the crushing excavator and its breaker 16, and thus ensuring the safety of the crushing excavator and its breaker 16.

[0051] In some alternative implementation manners of this embodiment, both the first overflow valve 4 and the second overflow valve 6 include electro-hydraulic proportional overflow valves.

[0052] With such a setting, when the boom cylinder 5 bears an impact load, the pressure of the rod chamber or the non-rod chamber rises to the set value of the first overflow valve 4 or the second overflow valve 6, and the first overflow valve 4 or the second overflow valve 6 opens. The high-pressure oil drives the breaker 16 to perform a downward or upward movement through the oil return port, and at the same time limits the cylinder pressure to avoid overload.

[0053] At the same time, due to the electro-hydraulic proportional characteristic, the pressure threshold can be adjusted in real time through the control device 2. By setting the first overflow valve 4 and the second overflow valve 6 as electro-hydraulic proportional overflow valves, the protection system for the working device of the special crushing excavator of the present invention can adapt to different working conditions.

[0054] In some alternative implementation manners of this embodiment, the display module includes a display, and the controls include one or more of buttons, keys or switches arranged on the display.

[0055] For the convenience of the operator's operation, the display module is arranged in the cab. Exemplarily, the display module includes a touch screen or physical buttons, so that preset parameters (such as upper pressure limit, overflow valve state adjustment) or custom parameters can be selected in the "crushing mode" through the physical buttons and the touch screen, and at the same time, information such as the pressure of the boom cylinder 5 and the working state of the breaker 16 can be displayed in real time through the touch screen.

[0056] In some alternative implementation manners of this embodiment, the detection device 7 includes any one or more of sensors or strain gauges.

[0057] Exemplarily, the detection device 7 is set as a piezoresistive pressure sensor with a measuring range of 0 - 40 MPa and an accuracy of ±0.1% FS. It detects the pilot pressure corresponding to the foot pedal operation signal in real time, such as 0.5 - 4 MPa, and converts it into an electrical signal (such as 0 - 5V) and transmits it to the control device 2.

[0058] Thus, the detection device 7 can provide quantitative data on the operator's operation intention, which is used for triggering the timing and force adjustment of the action of the breaker 16 in the closed-loop control.

[0059] As an example, the switching valve 10 adopts a two-position three-way electromagnetic reversing valve. Its control end is connected to the third control end of the control device 2 (receiving PWM signals), the oil inlet is connected to the pipeline from the pilot pump 12 to the boom pilot handle 9 (pressure range 2 - 5 MPa), and the oil outlet is connected to the pilot oil port of the breaker foot pedal 8.

[0060] It is switched on and off under the instruction of the control device 2 to realize the switching between the "breaker mode" and the "normal mode".

[0061] Exemplarily, for example, when the breaker mode is activated: the control device 2 outputs a high-level signal, the switching valve 10 changes its direction, and the pilot pressure oil drives the breaker foot pedal 8 through the oil outlet to activate the operation of the breaker 16;

[0062] When the normal mode is activated: the switching valve 10 resets, cutting off the pilot oil circuit, and the breaker 16 is in the disabled state.

[0063] In some optional implementation manners of this embodiment, the control device 2 is designed based on the ARM Cortex-M7 microcontroller device 2, integrating an AD acquisition module (for receiving sensor signals) and a DA output module (for driving the overflow valve). Its control methods include: pressure closed-loop control and breaker excavator breaker mode switching control, where:

[0064] The pressure closed-loop control includes: using the pressure signal of the detection device 7 as feedback, and dynamically adjusting the set value of the overflow valve through the PID algorithm. For example, when the sensor detects that the foot pedal pressure is 3 MPa (corresponding to high-intensity breaking requirements), the control device 2 outputs the corresponding voltage to the first overflow valve 4, raising the upper limit of the pressure in the rodless cavity to 28 MPa.

[0065] Furthermore, referring to Figure 1 and 2 , in an embodiment of the present invention, the multi-way valve assembly 3 includes: a first reversing valve 3.3, a second reversing valve 3.4, a check valve 3.2, a third overflow valve 3.1, and a main overflow valve 3.5, where:

[0066] The first working oil port of the first directional valve 3.3 serves as the first output port of the multi-way valve assembly 3, the second working oil port of the first directional valve 3.3 serves as the second output port of the multi-way valve assembly 3, the oil inlet of the first directional valve 3.3 serves as the first oil inlet of the multi-way valve assembly 3 and is connected to the oil outlet of the first hydraulic pump 14, the oil outlet of the first directional valve 3.3 is connected to the connecting pipeline of the third relief valve 3.1 connecting the second directional valve 3.4, the third working oil port of the first directional valve 3.3 is connected to the connecting pipeline of the oil inlet of the first directional valve 3.3, the fourth working oil port of the first directional valve 3.3 is connected to the connecting pipeline of the second directional valve 3.4 connecting the third relief valve 3.1, the first control of the first directional valve 3.3 serves as the third output port of the multi-way valve assembly 3 and is connected to the oil outlet of the crushing foot pedal 8, and the second control end of the first directional valve 3.3 is blocked; the first working oil port of the second directional valve 3.4 is connected to one end of the third relief valve 3.1, the oil inlet of the second directional valve 3.4 serves as the second oil inlet of the multi-way valve assembly 3 and is connected to the oil outlet of the second hydraulic pump 13, the second working oil port of the second directional valve 3.4 is connected to the connecting pipeline of the second oil inlet, the third working oil port of the second directional valve 3.4 serves as the fourth output port of the multi-way valve assembly 3 and is connected to the rod chamber of the boom cylinder 5, the fourth working oil port of the second directional valve 3.4 serves as the fifth output port of the multi-way valve assembly 3 and is connected to the rodless chamber of the boom cylinder 5, the oil outlet of the second directional valve 3.4 is connected to the connecting pipeline of the third relief valve 3.1 connecting the second directional valve 3.4, the first control end of the second directional valve 3.4 is connected to the oil outlet of a control valve in the boom pilot handle 9, and the second control end of the second directional valve 3.4 is connected to the oil outlet of another control valve in the boom pilot handle 9; the number of the third relief valves 3.1 and the check valves 3.2 are both set to be multiple, multiple third relief valves 3.1 are correspondingly and juxtaposedly connected to multiple check valves 3.2, one ends of multiple third relief valves 3.1 are respectively correspondingly connected to the first working oil port and the second working oil port of the first directional valve 3.3, and one ends of multiple third relief valves 3.1 are respectively correspondingly connected to the third working oil port and the fourth working oil port of the second directional valve 3.4, and the other ends of multiple third relief valves 3.1 are all connected to the first working oil port of the second directional valve 3.4; one end of the main relief valve 3.5 is connected to the connecting pipeline of the oil return port of the multi-way valve assembly 3, and the other end of the main relief valve 3.5 is divided into two connecting pipelines and is respectively connected to the first oil inlet and the second oil inlet of the multi-way valve assembly 3 through the check valves 3.2.

[0067] In some alternative implementation manners of this embodiment, both the first directional valve 3.3 and the second directional valve 3.4 include three-position six-way hydraulically controlled directional valves.

[0068] In addition, in the multi-way valve assembly 3 provided in an embodiment of the present invention, there are also multiple other check valves 3.2, and the connection relationship and positional relationship of the multiple other check valves 3.2 are as Figure 1 andFigure 2 as shown

[0069] Thus, the multi-way valve assembly 3 in an embodiment of the present invention can switch the oil circuit direction according to the operation instruction, and coordinate the combined actions of the boom lifting and the breaker 16 striking.

[0070] Exemplarily, when the operating lever pushes the boom down, the multi-way valve assembly 3 distributes the main pump oil to the rod chamber of the boom cylinder 5, causing the rod chamber to be filled with oil, and at the same time feeding back the foot-operated operation signal to the control device 2 through port B.

[0071] Further, referring to Figure 1 and Figure 2 , in the working device protection system of the breaker-specialized excavator in an embodiment of the present invention, a pilot relief valve 11 is further included. One end of the pilot relief valve 11 is connected to the fuel tank 15, and the other end is connected to the connecting pipeline of the pilot pump 12 connecting the boom pilot handle 9.

[0072] With such a setting, by setting the pilot relief valve 11 in the system of an embodiment of the present invention, when the system of the present invention is working properly, the pilot relief valve 11 remains closed. When the system pressure of the present invention exceeds the set value, the pilot relief valve opens for overload protection to prevent the system pressure from rising further.

[0073] Further, referring to Figure 1 and Figure 2 , in the working device protection system of the breaker-specialized excavator in an embodiment of the present invention, a first hydraulic pump 14 is further included. The suction port of the first hydraulic pump 14 is connected to the fuel tank 15, and the oil outlet of the first hydraulic pump 14 is connected to the first oil inlet of the multi-way valve assembly 3.

[0074] With such a setting, through the first hydraulic pump 14, a stable pressure can be provided for the main oil circuit (for example, a stable pressure of rated pressure 35 MPa), ensuring the stable supply of high-pressure oil in the main oil circuit.

[0075] Further, referring to Figure 1 and Figure 2 , in the working device protection system of the breaker-specialized excavator in an embodiment of the present invention, a second hydraulic pump 13 is further included. The second hydraulic pump 13 is rigidly connected to the first hydraulic pump 14 and the pilot pump 12. The suction port of the second hydraulic pump 13 is connected to the fuel tank 15, and the oil outlet of the second hydraulic pump 13 is connected to the second oil inlet of the multi-way valve assembly 3.

[0076] With such a setting, by setting the second hydraulic pump 13 in the system of an embodiment of the present invention, by connecting its oil discharge port to the auxiliary oil port of the multi-way valve assembly 3, the control oil port is linked with the pilot pump 12 to achieve optimized flow distribution and reduce the load fluctuation of the first hydraulic pump 14 (main pump).

[0077] The principle of a protection system for the working device of a crushing excavator according to the present invention includes:

[0078] Set the overflow pressure value of the main overflow valve 3.5 set by the manufacturer of the multi-way valve assembly 3 as A, and the overflow pressure values of the four third overflow valves 3.1 of the first reversing valve 3.3 and the second reversing valve 3.4 as B (usually B > A), the overflow pressure of the first overflow valve 4 as C, the overflow pressure of the second overflow valve 6 as D, the opening pressure of the first reversing valve 3.3 as K, and the pilot pressure output by the crushing foot pedal 8 as P;

[0079] Set the working device protection state as: the state where the external overflow valve pressures of the large and small chambers of the boom cylinder 5 are less than the pressure of the main overflow valve 3.5. At this time, the hydraulic circuit of the boom cylinder 5 is limited in pressure by the external overflow valves, the first overflow valve 4 and the second overflow valve 6; when the external overflow valve pressures of the large and small chambers of the boom cylinder 5 are both 0, both the large and small chambers of the boom cylinder 5 are connected to the fuel tank 15, and this is the floating state of the working device;

[0080] Set the shielding state of the overflow valve as: the external overflow valve pressure is set higher than the pressure of the third overflow valve 3.1. Due to the characteristics of the hydraulic circuit, the external overflow valve does not work at this time and is equivalent to being shielded. This shielding state includes: the large and small chambers of the boom, that is, the rodless chamber and the rod chamber of the boom cylinder 5 are correspondingly connected to the second overflow valve 6 and the first overflow valve 4, and are in the shielding state;

[0081] Pressing the boom is the boom lowering action. At this time, the small chamber of the boom cylinder is filled with oil. Therefore, the external electromagnetic valve for boom lowering adopts electro-hydraulic proportional control, enabling it to be adjusted in multiple levels to meet the requirements of different working conditions. In the shielding state, C > B, and in other cases, C ≤ A should be ensured;

[0082] The boom lifting is only used in the excavation working condition or when adjusting the working attitude. Therefore, the external overflow valve for boom lifting adopts two-point control, that is, there are only two states: D = 0 and D > B;

[0083] The necessary and sufficient conditions for the working device protection state include:

[0084] Crushing mode, P ≥ K, C < A, and D > B;

[0085] The necessary and sufficient conditions for the working device floating state include:

[0086] Crushing mode, P ≥ K, and C = D = 0.

[0087] It can be understood that the crushing excavator manufacturer can set signs to inform the driver of the recommended range of boom lowering pressure values for different rock working conditions. The driver can adjust according to the recommended values and the actual working conditions, and no setting and constraint are made on it in the embodiment of the present invention.

[0088] The specific working principle is as follows:

[0089] After the driver sets the excavator to the crushing mode through the display module 1, it automatically jumps to the crushing parameter setting page, and the control device 2 outputs a signal to the switching valve 10 to energize the coil of the switching valve 10 to work in the left position. At this time, the oil circuit between the pilot pump 12 and the crushing pedal 8 is opened, allowing the first reversing valve 3.3 in the multi-way valve assembly 3 to reverse. As Figure 3 shown, when the driver enters the crushing parameter setting page, the pressure adjustment slider and pressure value of the first overflow valve 4 can be visually seen. At the same time, the driver can read the status of the second overflow valve 6 through the lower indicator.

[0090] Working device floating state:

[0091] As Figure 3 and Figure 4 shown, after entering the crushing parameter setting page, the driver drags the pressure adjustment slider of the first overflow valve 4 to the floating end (the leftmost end), and the program control highlights the floating indicator point below the external overflow valve state of the boom lift. When the driver clicks the save button in the lower right corner of the display module 1, the control device 2 will record the data. After the driver steps on the crushing pedal 8, the detection device 7 transmits the detected pilot pressure data to the control device 2. The control device 2 compares the received pilot pressure data with the opening pressure of the spool of the multi-way valve assembly 3. When the pilot pressure is greater than or equal to the opening pressure of the spool of the multi-way valve assembly 3, the pressures C and D of the boom cylinder large and small chamber overflow valves are adjusted to 0 through an electrical signal. At this time, both the large and small chambers of the boom cylinder 5 are connected to the fuel tank 15, and the excavator relies on the gravity of the working device to press the hammer, playing a role in protection and energy saving. When the pilot pressure is less than the opening pressure of the spool of the multi-way valve assembly 3, both external solenoid valves return to the shielded state;

[0092] Working device protection state:

[0093] As Figure 3 and Figure 4As shown, after entering the crushing parameter setting page, the driver drags the pressure adjustment slider of the first overflow valve 4 to any position except the floating end and the shielding end. The program control will light up the shielding indication point below the external overflow valve state of the boom lift. When the driver clicks the save button at the lower right corner of the display module 1, the control device 2 will record the data. After the driver steps on the crushing foot pedal 8, the detection device 7 transmits the detected pilot pressure data to the control device 2. The control device 2 compares the received pilot pressure data with the opening pressure of the spool of the multi-way valve assembly 3. When the pilot pressure is greater than or equal to the opening pressure of the spool of the multi-way valve assembly 3, the control device 2 adjusts the pressure C of the first overflow valve 4 to the pressure value displayed above the slider through an electrical signal, and adjusts the pressure D of the external electro-hydraulic proportional overflow valve (serial number 6) of the boom lift to the shielding pressure. At this time, 0 < C < A < B, and the downward pressure of the boom cylinder 5 is controlled, avoiding excessive hammer pressing and protecting the working device. When the pilot pressure is less than the opening pressure of the spool of the multi-way valve assembly 3, both external solenoid valves return to the shielding state.

[0094] In summary, for the working device protection system of a crushing excavator according to the present invention, only after meeting the corresponding conditions above, the first overflow valve 4 and the second overflow valve 6 will intervene in the control. With such a setting, it can ensure that when not hammering, the boom cylinder 5 operates normally. And when the first overflow valve 4 intervenes in the control, the rest are all shielded, and the downward pressure of the boom is restricted, which can avoid excessive hammer pressing caused by improper operation of the driver, thereby reducing the pressure impact on the working device, effectively protecting the working device, and not affecting operations such as excavation and adjusting the posture of the breaker 16, taking into account the functions specific to traditional crushing excavators; at the same time, introducing the working device floating function on the crushing excavator, making the hammer pressing action rely on the self-weight of the working device and not being controlled by the driver, which has a good energy-saving effect on the basis of protecting the working device.

[0095] Thus, through the close cooperation of components such as the switching valve 10, the first overflow valve 4, the second overflow valve 6, and the detection device 7, the present invention realizes the control of the downward pressure of the working device of the crushing excavator, ensuring the safety of the crushing excavator and its breaker 16.

[0096] In a second aspect, as Figure 5 shown, the present invention also provides a protection method applying the above-mentioned working device protection system of a crushing excavator. The method includes:

[0097] Step S1: Control the switching valve 10 to open or close to switch the oil circuit connection between the pilot pump 12 and the crushing foot pedal 8, activating or disabling the operation of the breaker 16;

[0098] Step S2: Set the corresponding upper limit values of the pressure in the rod chamber and the non-rod chamber of the boom cylinder 5 according to different construction sites of the crushing excavator, such as different rock conditions;

[0099] Step S3: Continuously detect the medium pressure in the pipeline connecting the multi-way valve assembly 3 to the breaker foot pedal 8, and feedback the pressure signal to the control device 2;

[0100] Step S4: Dynamically adjust the control signals of the first relief valve 4 and the second relief valve 6 according to the pressure signal and the preset parameters of the excavator breaker mode, so as to adjust the upper limit values of the pressures in the rod chamber and the non-rod chamber of the boom cylinder 5;

[0101] Step S5: When the actual pressure in the rod chamber or the non-rod chamber of the boom cylinder 5 reaches the corresponding upper limit value of the pressure, control the opening of the corresponding first relief valve 4 or the second relief valve 6, so that the breaker 16 can drive the working device to perform a lowering or lifting action, making the force of the working device pressing the hammer tend to be stable, thereby reducing the impact force received by the working device;

[0102] Step S6: Real-time display the boom oil chamber pressure and the working state information of the breaker 16 on the display module 1, and update the parameter settings according to the operation instructions, so that the breaker 16 performs the breaking operation according to the set parameters and working modes.

[0103] Among them, dynamically adjusting the control signals of the first electro-hydraulic proportional relief valve and the second electro-hydraulic proportional relief valve specifically includes: converting the upper limit value of the pressure into a 0-10V voltage signal or a 4-20mA current signal according to the preset pressure-electric signal mapping relationship and outputting it to the corresponding relief valve; when it is detected that the pipeline pressure fluctuation exceeds the threshold, correcting the control signal through the PID algorithm to stabilize the pressure.

[0104] In addition, in the embodiment of the present invention, a pilot relief valve 11 is also included to limit the output pressure of the pilot pump 12. When the pilot pressure exceeds 3.9 MPa, the relief valve opens for unloading to protect the control oil circuit.

[0105] It should be noted that the pilot relief valve of general excavators is 3.9 MPa. Therefore, the pilot pressure is set to 3.9 MPa in the embodiment of the present invention, but it does not mean that 3.9 MPa is the only limitation to the present invention.

[0106] Thus, for a protection method of the working device of a breaker excavator according to the present invention, when the boom cylinder 5 bears an impact load, the pressure in the rod chamber or the non-rod chamber rises to the set value of the relief valve, and the relief valve opens to limit the cylinder pressure, so that the breaker 16 can drive the working device to perform a lowering or lifting action, thereby reducing the impact received by the working device. The first relief valve 4 and the second relief valve 6 with electro-hydraulic proportional characteristics enable the pressure threshold to be adjusted in real time by the controller to adapt to different working conditions, so as to prevent excessive downward pressure by adjusting the upper limit values of the pressures in the large and small chambers of the boom cylinder 5 to extend the machine life, and have a better energy-saving effect on the basis of protecting the working device.

[0107] It should be noted that in this text, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device. In addition, in this text, "front", "rear", "left", "right", "upper" and "lower" are all referenced with respect to the placement state shown in the drawings.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A protection system for the working device of a crushing excavator, characterized in that, Comprising: A first overflow valve, the inlet port of the first overflow valve is connected to the connecting pipeline of the multi-way valve assembly connecting the rod chamber of the boom cylinder, the return port of the first overflow valve is connected to the fuel tank, and the control oil port of the first overflow valve is connected to the first control end of the control device, so as to control the pressure of the rod chamber of the boom cylinder of the crushing excavator under the control of the control device; A second overflow valve, the inlet port of the second overflow valve is connected to the connecting pipeline of the multi-way valve assembly connecting the rodless chamber of the boom cylinder, the return port of the second overflow valve is connected to the return port of the first overflow valve and then connected to the fuel tank, and the control oil port of the second overflow valve is connected to the second control end of the control device, so as to control the pressure of the rodless chamber of the boom cylinder of the crushing excavator under the control of the control device; A multi-way valve assembly, one working oil port of the multi-way valve assembly is connected to the breaker of the crushing excavator, and is used to control the movement direction of the breaker rod by controlling the flow direction of the hydraulic oil. The other two working oil ports of the multi-way valve assembly are respectively connected to the rod chamber and the rodless chamber of the boom cylinder, and are used to control the telescopic movement of the boom cylinder by controlling the flow direction of the hydraulic oil, thereby controlling the rise or fall of the working device of the crushing excavator; A detection device, the detection device is connected to the outlet connecting pipeline of the breaker pilot valve core of the multi-way valve assembly connecting the breaker pedal of the crushing excavator, and is used to detect the medium pressure in the connecting pipeline where the detection device is located; A switching valve, the control end of the switching valve is connected to the third control end of the control device, the inlet port of the switching valve is connected to the connecting pipeline of the pilot pump connecting the boom pilot handle, and the outlet port of the switching valve is connected to the inlet port of the breaker pedal; A control device, the control device is used to control the opening pressure or on-off of the first overflow valve, the second overflow valve and the switching valve, so that the control device can adjust the upper limit values of the pressure of the rod chamber of the boom cylinder and the rodless chamber of the boom cylinder by controlling the opening pressure of the first overflow valve and the second overflow valve, and the control device can also control the on-off of the oil inlet of the breaker pedal by controlling the on-off of the switching valve. A display module, the display module is connected to the control device, and a setting page and a display interface for setting the crushing excavator to the crushing mode or setting crushing parameters are set on the display module, and controls for displaying adjustment and parameter setting are set on the setting page and the display interface, so that the crushing mode and crushing parameters of the crushing excavator can be set on the setting page and the display interface through the controls.

2. The protection system for the working device of a crushing excavator according to claim 1, wherein, Both the first overflow valve and the second overflow valve include electro-hydraulic proportional overflow valves.

3. The protection system for the working device of a crushing excavator according to claim 1, characterized in that, The multi-way valve assembly includes: The first reversing valve, the first working oil port of the first reversing valve serves as the first output port of the multi-way valve assembly, the second working oil port of the first reversing valve serves as the second output port of the multi-way valve assembly, the oil inlet of the first reversing valve serves as the first oil inlet of the multi-way valve assembly and is connected to the oil outlet of the first hydraulic pump, the oil outlet of the first reversing valve is connected to the connecting pipeline where the third overflow valve is connected to the second reversing valve, the third working oil port of the first reversing valve is connected to the connecting pipeline where the oil inlet of the first reversing valve is located, the fourth working oil port of the first reversing valve is connected to the connecting pipeline where the second reversing valve is connected to the third overflow valve, the first control of the first reversing valve serves as the third output port of the multi-way valve assembly and is connected to the oil outlet of the crushing foot pedal, and the second control end of the first reversing valve is blocked; The second reversing valve, the first working oil port of the second reversing valve is connected to one end of the third overflow valve, the oil inlet of the second reversing valve serves as the second oil inlet of the multi-way valve assembly and is connected to the oil outlet of the second hydraulic pump, the second working oil port of the second reversing valve is connected to the connecting pipeline of the second oil inlet, the third working oil port of the second reversing valve serves as the fourth output port of the multi-way valve assembly and is connected to the rod chamber of the boom cylinder, the fourth working oil port of the second reversing valve serves as the fifth output port of the multi-way valve assembly and is connected to the rodless chamber of the boom cylinder, the oil outlet of the second reversing valve is connected to the connecting pipeline where the third overflow valve is connected to the second reversing valve, the first control end of the second reversing valve is connected to the oil outlet of one control valve in the boom pilot handle, and the second control end of the second reversing valve is connected to the oil outlet of the other control valve in the boom pilot handle; [[ID= ​ ​ 4. The protection system for the working device of a crushing excavator according to claim 3, characterized in that, ​ 5. The protection system for the working device of a crushing excavator according to claim 1, characterized in that, ​ 6. The protection system for the working device of a crushing excavator according to claim 1, characterized in that, ​ 7. A protection system for the working device of a crushing excavator according to claim 3, characterized in that, ​ 8. The protection system for the working device of a crushing excavator according to claim 7, characterized in that, ​ 9. The protection system for the working device of a crushing excavator according to claim 8, characterized in that, It further includes a second hydraulic pump, which is rigidly connected to the first hydraulic pump and the pilot pump. The oil suction port of the second hydraulic pump is connected to the fuel tank, and the oil outlet of the second hydraulic pump is connected to the second oil inlet of the multi-way valve assembly.

10. A protection method for a protection system of a working device of a crushing excavator applying the protection system according to any one of claims 1-9, characterized in that, Comprising: Controlling the opening or closing of the switch valve to switch the oil path connection between the pilot pump and the breaker foot pedal, activating or disabling the breaker operation; Setting the corresponding upper pressure limit values and working modes for the rod chamber and the non-rod chamber of the boom cylinder according to different breaker modes of the breaker excavator; Real-time detecting the medium pressure in the pipeline connecting the multi-way valve assembly to the breaker foot pedal and feeding back the pressure signal to the control device; Dynamically adjusting the control signals of the first relief valve and the second relief valve according to the pressure signal and the preset parameters of the excavator breaker mode to adjust the upper pressure limit values of the rod chamber and the non-rod chamber of the boom cylinder; When the actual pressure of the rod chamber or the non-rod chamber of the boom cylinder reaches the corresponding upper pressure limit value, controlling the opening of the corresponding first relief valve or the second relief valve so that the breaker can drive the working device to perform the lowering or lifting action, making the force of the working device pressing the hammer tend to be stable; Real-time displaying the boom oil chamber pressure and the breaker working state information on the display module, and updating the parameter settings according to the operation instruction, so that the breaker performs the breaking operation according to the set parameters and working modes.

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