New energy engineering machinery and hydraulic braking system and method thereof

Abstract

The invention relates to the technical field of engineering machinery, and discloses new energy engineering machinery and a hydraulic braking system and method thereof, the engineering machinery comprises at least two execution elements, and the hydraulic braking system comprises a brake pedal, a brake oil way, an electric proportional regulating valve and a control module; the brake oil way comprises an oil supply way used for supplying oil to the multiple execution elements. The electric proportional regulating valve is arranged on the oil supply path and is used for regulating the working pressure of the execution element; the control module is electrically connected with the brake pedal and the electric proportioning valve and is configured to obtain an input voltage signal of the brake pedal; converting an input voltage signal into a control current signal; and controlling the opening degree of the electric proportioning valve according to the control current signal. According to the technical scheme, corresponding brake pressure can be matched for different drive axles, the model of the brake pedal does not need to be changed for different drive axles, and the universality of the brake pedal is improved.

Description

Technical Field

[0001] The present application belongs to the technical field of engineering machinery, and specifically relates to a new energy engineering machinery and a hydraulic braking system and method thereof. Background Art

[0002] In the braking system of construction machinery, such as the braking system of off-road tire cranes, full hydraulic braking is usually used, and the gear pump is used as the power source to provide power for the braking system. According to the current development trend of construction machinery, the new energy architecture has a certain scale, so the above-mentioned braking system can also be adapted to the new energy architecture. The brake pedal is used as a brake control element. It can output different brake pressures according to the different pedal angles of the brake pedal. The brake pressure acts on the drive axle to realize the driving brake function. During the braking process, the maximum brake pressure output by the brake pedal is generally a fixed value. The maximum brake pressure required for different axles is different. Different axles need to change the brake pedal model, and the universality is poor. Summary of the invention

[0003] The purpose of the present application is to provide a new energy engineering machinery and its hydraulic braking system and method, so as to distribute different braking pressures according to different front and rear drive axles.

[0004] In order to achieve the above-mentioned object, the present application provides a hydraulic brake system of an engineering machine on one hand, wherein the engineering machine includes at least two actuators, and the hydraulic brake system includes:

[0005] Brake pedal;

[0006] A brake oil circuit, comprising oil supply circuits for supplying oil to the plurality of actuators respectively;

[0007] An electric proportional regulating valve, arranged on the oil supply line and used for regulating the working pressure of the actuator;

[0008] A control module is electrically connected to the brake pedal and the electric proportional control valve and is configured as follows:

[0009] Acquiring an input voltage signal of the brake pedal;

[0010] Converting the input voltage signal into a control current signal;

[0011] The opening of the electric proportional control valve is controlled according to the control current signal.

[0012] In some embodiments, the control module includes a boarding control unit and an getting-off control unit that are communicatively connected, the boarding control unit is electrically connected to the brake pedal, the boarding control unit is used to receive the input voltage signal sent by the brake pedal and send it to the getting-off control unit, and the getting-off control unit is used to convert the input voltage signal into the control current signal.

[0013] In some embodiments, a connecting oil circuit is connected between the plurality of oil supply circuits, the connecting oil circuit is located between the actuator and the electric proportional control valve, a shuttle valve and a pressure detection element are provided on the connecting oil circuit, the pressure detection element is used to detect the working pressure of the plurality of actuators, the shuttle valve is used to obtain the maximum working pressure value among the plurality of working pressures and feed it back to the getting off control unit, and the getting off control unit is further configured as follows:

[0014] Obtaining a maximum working pressure value among the multiple working pressures;

[0015] Comparing the maximum working pressure value with the theoretical working pressure value;

[0016] Determine the working status of the hydraulic brake system based on the comparison results.

[0017] In some embodiments, the hydraulic braking system also includes an oil pump and a filling valve group, wherein the filling valve group is arranged on the connecting oil circuit between the electric proportional control valve and the oil pump, and within a preset pressure range, the filling valve group is used to conduct the connecting oil circuit between the electric proportional control valve and the oil pump.

[0018] In some embodiments, the filling valve group includes a reversing valve assembly and a filling valve that are integrated into one body, the reversing valve assembly includes two parallel reversing valves, one side working oil ports of the two reversing valves are respectively connected to the two electric proportional control valves, one side oil port of the filling valve is connected to the other side working oil port of the reversing valve, and the other side oil port of the filling valve is switched and connected to the oil pump or other oil circuits.

[0019] In some embodiments, the hydraulic brake system further includes an accumulator, and the accumulator is disposed on the connecting oil circuit between the charging valve and the proportional control valve.

[0020] A second aspect of the present application provides a braking control method for an engineering machine, which is applied to the braking system as described above. The braking control method comprises the following steps:

[0021] Acquiring an input voltage signal of the brake pedal;

[0022] Converting the input voltage signal into a control current signal;

[0023] controlling the opening of the electric proportional control valve according to the control current signal;

[0024] The working pressure of the corresponding actuator is adjusted according to the opening degree of the electric proportional control valve.

[0025] In some embodiments, the step of converting the input voltage signal into a control current signal comprises:

[0026] Acquiring the current operating condition of the engineering machinery;

[0027] Selecting a corresponding braking curve according to the current operating condition of the engineering machinery;

[0028] The input voltage signal is input into the braking curve to obtain the control current signal.

[0029] In some embodiments, the braking control method further comprises the steps of:

[0030] Calculating a theoretical working pressure value of the actuator according to a stepping angle of the brake pedal;

[0031] Obtaining a maximum working pressure value among the working pressures of the plurality of actuators;

[0032] Comparing the maximum working pressure value with the theoretical working pressure value;

[0033] Determine the working status of the hydraulic brake system based on the comparison results.

[0034] In some embodiments, the step of determining the working state of the hydraulic brake system according to the comparison result includes:

[0035] Acquire a working pressure error value according to the maximum working pressure value and the theoretical working pressure value;

[0036] When the working pressure error value is in the range of -5% to 5%, it is judged that the hydraulic brake system is working normally;

[0037] When the working pressure error value ranges from -10% to -5% or from 5% to 10%, it is determined that the hydraulic brake system is abnormal.

[0038] In some embodiments, the step of determining the working state of the hydraulic brake system according to the comparison result further includes:

[0039] When the maximum working pressure value is greater than the theoretical working pressure value, and the working pressure error value is greater than 10%, it is determined that the hydraulic brake system is abnormal and an alarm is issued;

[0040] When the maximum working pressure value is greater than the theoretical working pressure value, and the working pressure error value is greater than 20%, the hydraulic brake system is judged to be abnormal and an alarm is sounded, and at the same time, the driving function of the engineering machinery is cut off and emergency braking is performed;

[0041] When the maximum working pressure value is less than the theoretical working pressure value, and the working pressure error value is greater than 10%, the hydraulic brake system is judged to be abnormal and an alarm is issued, and at the same time, the driving function of the engineering machinery is cut off and emergency braking is performed.

[0042] A third aspect of the present application provides a new energy engineering machinery, comprising the braking system as described above.

[0043] Through the above technical scheme, the hydraulic brake system of the present application includes a brake pedal and a brake oil circuit, the brake oil circuit includes an oil supply circuit for supplying oil to multiple actuators respectively; an electric proportional control valve is arranged on the oil supply circuit and is used to adjust the working pressure of the actuator; when adjusting the working pressure of the actuator, the input voltage signal of the brake pedal is first obtained, and then the input voltage signal is converted into a control current signal, and finally the opening of the electric proportional control valve is controlled according to the control current signal; by changing the opening of the electric proportional control valve to affect the hydraulic oil pressure entering the drive axle, the purpose of adjusting the working pressure of different actuators can be achieved, so that different brake pressures can be allocated to different actuators, thereby improving the versatility of the entire system.

[0044] Other features and advantages of the embodiments of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without creative work. In the drawings:

[0046] Figure 1 A schematic diagram of the hydraulic principle of a hydraulic brake system of an engineering machinery according to the present application;

[0047] Figure 2 A schematic diagram of the interaction relationship between various modules in the braking control method of engineering machinery according to the present application;

[0048] Figure 3 It is a braking curve diagram in the hydraulic braking system of the engineering machinery according to the present application.

[0049] Description of Reference Numerals

[0050] 1 Oil pump 61 Shuttle valve

[0051] 2 Filling valve group 62 Pressure detection part

[0052] 21 Filling valve 71 Front drive axle

[0053] 22 Directional valve 72 Rear drive axle

[0054] 3 Accumulator 81 Onboard control unit

[0055] 4 Brake pedal 82 Exit control unit

[0056] 5 Electric proportional control valve 90 GPS module DETAILED DESCRIPTION

[0057] The specific implementation of the present application is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present application, and is not used to limit the present application.

[0058] The following describes the new energy engineering machinery and its hydraulic braking system and method according to the present application with reference to the accompanying drawings. The hydraulic braking system of the present application can be applied to fuel architecture and new energy architecture, wherein the vehicle models of the new energy architecture generally include: pure electric, extended-range electric, hybrid, fuel cell electric, hydrogen engine, etc.

[0059] like Figure 1 As shown, the present application provides a hydraulic brake system for engineering machinery, the engineering machinery includes at least two actuators, the hydraulic brake system includes a brake pedal 4, a brake oil circuit, an electric proportional control valve 5 and a control module; the brake oil circuit includes an oil supply circuit for supplying oil to multiple actuators respectively; the electric proportional control valve 5 is arranged on the oil supply circuit and is used to adjust the working pressure of the actuator; the control module is electrically connected to the brake pedal 4 and the electric proportional control valve 5 and is configured to: obtain an input voltage signal of the brake pedal 4; convert the input voltage signal into a control current signal; and control the opening of the electric proportional control valve 5 according to the control current signal.

[0060] For the braking system of engineering machinery, the actuator can be a corresponding braking element. For example, in a crane, the actuator can be two and they are respectively the front drive axle 71 and the rear drive axle 72. The hydraulic braking system of the present application adopts a dual-circuit braking system. The front drive axle 71 and the rear drive axle 72 correspond to two independent oil supply circuits, respectively. An electric proportional control valve 5 is arranged on each oil supply circuit. The working oil port on one side of the electric proportional control valve 5 is connected to the front drive axle 71 / rear drive axle 72, and the working oil port on the other side is connected to the oil tank. In this way, the hydraulic oil pumped from the oil tank needs to pass through the electric proportional control valve 5 during the process of supplying to the drive axle. The opening of the electric proportional control valve 5 controls the pressure of the hydraulic oil entering the drive axle. Therefore, the present application obtains the corresponding input voltage signal according to the pedaling angle of the brake pedal 4, and converts the input voltage signal into a control current signal. The opening of the electric proportional control valve 5 is controlled by the control current signal, thereby achieving the purpose of adjusting the working pressure of different drive axles. By adopting the technical solution of the present application, corresponding brake pressures can be matched for different drive axles, and there is no need to change the model of the brake pedal 4 for different drive axles, thereby improving the versatility of the brake pedal 4.

[0061] like Figure 2 As shown, the control module includes a communication-connected boarding control unit 81 and a disembarking control unit 82, wherein the boarding control unit 81 is installed on the driver's cab of the engineering machinery, and the disembarking control unit 82 is installed on the disembarking assembly of the engineering machinery. The boarding control unit 81 is electrically connected to the brake pedal 4, wherein the brake pedal 4 is an electronic brake pedal 4, which can feedback a certain input voltage signal according to the operator's pedaling angle, and the boarding control unit 81 is used to receive the input voltage signal sent by the brake pedal 4 and send it to the disembarking control unit 82, and the disembarking control unit 82 is used to receive the input voltage signal sent by the boarding control unit 81 and can convert the input voltage signal into a control current signal. In this embodiment, through the communication and interaction setting between the boarding control unit 81, the disembarking control unit 82, and the first-level brake pedal 4, the drive axle can intelligently match the optimal braking force, thereby improving the driving experience.

[0062] In some embodiments, a connecting oil circuit is connected between the multiple oil supply circuits, and the connecting oil circuit is located between the actuator and the electric proportional control valve 5. A shuttle valve 61 and a pressure detection element 62 are provided on the connecting oil circuit. The pressure detection element 62 is used to detect the working pressure of the multiple actuators. The shuttle valve 61 is used to obtain the maximum working pressure value among the multiple working pressures and feed it back to the getting off control unit 82. The getting off control unit 82 is further configured as follows:

[0063] Obtain the maximum working pressure value among multiple working pressures;

[0064] Compare the maximum working pressure value with the theoretical working pressure value;

[0065] Determine the working status of the hydraulic brake system based on the comparison results.

[0066] Among them, the pressure detection member 62 can be a pressure sensor. In this application, by adding a shuttle valve 61 and a pressure sensor to the oil supply line, the vehicle disembarkation control unit 82 can match the expected brake pressure value according to the working condition according to the voltage signal input by the brake pedal 4, and the pressure sensor can detect the working pressure values ​​of the front drive axle 71 and the rear drive axle 72 in real time. The vehicle disembarkation control unit 82 can diagnose the brake system state according to the difference between the expected theoretical working pressure value and the actual value, and the braking safety is better.

[0067] In addition, the control module also includes a GPS module 90 that is communicatively connected to both the getting-off control unit 82 and the getting-on control unit 81. The getting-off control unit 82 can provide feedback to the GPS module 90 based on the abnormal difference between the measured maximum working pressure value and the theoretical working pressure value. The GPS module 90 reports a vehicle abnormality alarm based on the feedback signal, and feeds back the abnormal signal to the customer, reminding the customer to perform vehicle inspection and maintenance.

[0068] In some embodiments, the hydraulic brake system further includes an oil pump 1 and a charging valve group 2. The charging valve group 2 is disposed on the connecting oil circuit between the electric proportional regulating valve 5 and the oil pump 1. Within a preset pressure range, the charging valve group 2 is used to conduct the connecting oil circuit between the electric proportional regulating valve 5 and the oil pump 1. In this embodiment, by providing the charging valve group 2, it is possible to ensure that the hydraulic oil in the oil supply circuits of the two drive axles is within a suitable range, thereby preventing emergency braking caused by excessive pressure or affecting the braking effect due to insufficient pressure.

[0069] In some embodiments, the filling valve group 2 includes a reversing valve 22 assembly and a filling valve 21 that are integrated into one body. The reversing valve 22 assembly includes two parallel reversing valves 22. The working oil ports on one side of the two reversing valves 22 are respectively connected to the two electric proportional control valves 5. The oil port on one side of the filling valve 21 is connected to the working oil port on the other side of the reversing valve 22. The oil port on the other side of the filling valve 21 is switched and connected to the oil pump 1 or other oil circuits.

[0070] like Figure 1As shown, the reversing valve 22 assembly includes two parallel reversing valves 22, and one side oil port of the two reversing valves 22 is separately connected to the front drive axle 71 and the rear drive axle 72 oil, and the two reversing valves 22 are switched at the same time, and the oil circuit is connected or cut off at the same time. The filling valve 21 has two switching positions. When the pressure of the hydraulic oil pumped by the oil pump 1 is within the preset range, the hydraulic oil is in the left position and the oil circuits where the front drive axle 71 and the rear drive axle 72 are located are preferentially supplied with oil; when the pressure of the hydraulic oil exceeds the preset pressure value, the filling valve 21 is pushed to the right position under the action of the hydraulic oil. At this time, the preset amount of hydraulic oil is used to supply oil to the oil circuits where the front drive axle 71 and the rear drive axle 72 are located, and the excess hydraulic oil is used to supply oil to other oil circuits.

[0071] In some embodiments, the hydraulic brake system further includes an accumulator 3, which is disposed on the connecting oil circuit between the charging valve 21 and the proportional regulating valve. The accumulator 3 stores spare hydraulic oil. When the oil pump 1 or the charging valve group 2 fails, the hydraulic oil pumped from the oil tank cannot be delivered to the front drive axle 71 and the rear drive axle 72. The accumulator 3, as a spare auxiliary power source, can meet the normal braking function of the vehicle in the above emergency state and provide brake hydraulic oil power for the front drive axle 71 and the rear drive axle 72. There can be two accumulators 3, which provide auxiliary power sources for the front drive axle 71 and the rear drive axle 72 respectively.

[0072] A second aspect of the present application provides a braking control method for an engineering machine, which is applied to the braking system as described above. The braking control method comprises the following steps:

[0073] Acquiring an input voltage signal of the brake pedal 4;

[0074] Convert the input voltage signal into a control current signal;

[0075] Controlling the opening of the electric proportional control valve 5 according to the control current signal;

[0076] The working pressure of the corresponding actuator is adjusted according to the opening degree of the electric proportional control valve 5.

[0077] When braking the actuator of the construction machinery, first obtain the input voltage signal of the brake pedal 4, then convert the input voltage signal into a corresponding control current signal, send the control current signal to the electric proportional control valve 5, and control the opening of the electric proportional control valve 5 by controlling the current signal, thereby controlling the working pressure flowing to the actuator. The braking control method of the present application can realize automatic and intelligent regulation of the working pressure of the drive axle, so that different braking forces can be matched to different drive axles, thereby improving the versatility of the brake pedal 4 and the braking safety of the whole machine.

[0078] Since the braking power required for the front drive axle 71 and the rear drive axle 72 under different working conditions is different, in the prior art, hydraulic braking is usually unable to distribute the braking pressure of the front drive axle 71 and the rear drive axle 72 according to different working conditions. In order to solve the existing technical problems, the brake control method of the present application is further refined.

[0079] Specifically, in some embodiments, the step of converting the input voltage signal into a control current signal includes:

[0080] Obtain the current operating conditions of the construction machinery;

[0081] Select the corresponding braking curve according to the current working condition of the construction machinery;

[0082] The input voltage signal is input into the braking curve to obtain the control current signal.

[0083] In this embodiment, the present application can intelligently distribute the braking force of the front drive axle 71 and the rear drive axle 72 according to different operating conditions. Taking the construction machinery as an off-road tire crane as an example, since the off-road tire crane has two operating conditions: loaded driving and normal driving. The disembarkation control unit 82 can read the operating conditions set by the system in the on-board control unit 81. Since the front drive axle 71 bears the main load under the loaded driving condition, the disembarkation control unit 82 is adjusted under this condition to automatically match the braking curve under the loaded driving condition, increase the braking force proportion of the front drive axle 71, and thus improve the braking effect under the loaded driving condition. Under normal driving conditions, since the loads of the front drive axle 71 and the rear drive axle 72 are comparable, appropriately increasing the braking force proportion of the rear drive axle 72 can effectively avoid the brake nodding phenomenon during braking and improve the driving comfort of the chassis.

[0084] During matching, by inputting the input voltage signal of the brake pedal 4 into the brake curve of the corresponding working condition, a control current signal matching the input voltage signal under the current working condition can be obtained, so that the opening of the electric proportional control valve 5 can be controlled according to the control current signal, thereby adjusting the oil pressure entering the front drive axle 71 and the rear drive axle 72, thereby achieving the optimal matching effect of the brake pressure and improving the driving experience. Figure 3 As shown, as the angle of the brake pedal 4 gradually increases, the brake pressure of the drive axle gradually increases until it stabilizes. Since the input voltage of the brake pedal 4 affects the angle of the brake pedal 4, the greater the input voltage, the greater the angle of the brake pedal 4. It should be noted that Figure 3 Middle bridge 1 refers to the rear drive bridge 72, and bridge 2 refers to the front drive bridge.

[0085] In some embodiments, the braking control method further comprises the steps of:

[0086] Calculate the theoretical working pressure value of the actuator according to the stepping angle of the brake pedal 4;

[0087] Obtaining the maximum working pressure value among the working pressures of multiple actuators;

[0088] Compare the maximum working pressure value with the theoretical working pressure value;

[0089] Determine the working status of the hydraulic brake system based on the comparison results.

[0090] When obtaining the maximum working pressure value, the working pressure of the front drive axle 71 and the rear drive axle 72 is detected in real time through pressure sensing, and the shuttle valve 61 compares the maximum value of the two in real time and feeds back to the vehicle exit control unit 82. Since the brake pedal 4 corresponds to a theoretical working pressure value (i.e., brake pressure) at the current pedaling angle under different working conditions, the vehicle exit control unit 82 retrieves the theoretical working pressure value and compares it with the maximum working pressure value, and determines whether the current hydraulic brake system is in an abnormal state according to the comparison result.

[0091] Furthermore, when the angle range of the brake pedal 4 is 4°≤T<12°, the theoretical working pressure value can be obtained by the following calculation formula:

[0092] P2=1+(T-1)÷2×1.5

[0093] Wherein, P2 is the theoretical working pressure value, and T is the angle of the brake pedal 4 .

[0094] When the angle range of the brake pedal 4 is 12°≤T<22°, the theoretical working pressure value can be obtained by the following calculation formula:

[0095] P2=7+(P-7)÷12×(T-12)

[0096] When the angle of the brake pedal 4 is greater than or equal to 22°, P2=P1, wherein P1 is the maximum braking pressure value of the axle.

[0097] Furthermore, a display screen is also provided in the engineering machinery, which can display the difference between the theoretical working pressure value and the maximum working pressure value in real time to detect the result of the braking system state, and can timely alarm and remind the driver when abnormalities are found, and can perform emergency braking in necessary emergency situations, thereby improving safety. The braking control method of the present application realizes intelligent control, remote control and diagnosis functions, which not only improves the versatility of the brake pedal 4, but also improves the driving experience and safety of the vehicle.

[0098] In some embodiments, the step of determining the working state of the hydraulic brake system according to the comparison result includes:

[0099] Obtain the working pressure error value according to the maximum working pressure value and the theoretical working pressure value;

[0100] When the working pressure error value ranges from -5% to 5%, it is judged that the hydraulic brake system is working normally;

[0101] When the working pressure error value ranges from -10% to -5% or from 5% to 10%, it is determined that the hydraulic brake system is abnormal.

[0102] When the brake pedal 4 is stepped on, some oil will be lost in the hydraulic oil circuit during the transmission process. Therefore, there will be a certain error between the actual working pressure value reaching the drive axle and the theoretical working pressure value calculated theoretically. According to the analysis of the experimental results, it is believed that when the working pressure error value ranges from -5% to 5%, the hydraulic brake system is working normally.

[0103] When the working pressure error value is in the range of -10% to -5% or 5% to 10%, it indicates that the hydraulic brake system is abnormal; at this time, the abnormal situation may be that the pedaling angle of the brake pedal 4 cannot meet the actual braking demand of the drive axle, or the brake pedal 4 brakes the drive axle too much under normal pedaling conditions and there is a risk of emergency braking. The above situations can all be considered as abnormal states. At this time, the abnormal signal can be reported as vehicle abnormal alarm information, and the abnormal information can be fed back to the customer to remotely remind the customer to inspect and maintain the vehicle.

[0104] In some embodiments, the step of determining the working state of the hydraulic brake system according to the comparison result further includes:

[0105] When the maximum working pressure value is greater than the theoretical working pressure value, and the working pressure error value is greater than 10%, the hydraulic brake system is judged to be abnormal and an alarm is issued;

[0106] When the maximum working pressure value is greater than the theoretical working pressure value, and the working pressure error value is greater than 20%, the hydraulic brake system is judged to be abnormal and an alarm is sounded, and the driving function of the construction machinery is cut off and emergency braking is performed;

[0107] When the maximum working pressure value is less than the theoretical working pressure value and the working pressure error value is greater than 10%, the hydraulic brake system is judged to be abnormal and an alarm is issued, and the driving function of the construction machinery is cut off and emergency braking is performed.

[0108] Furthermore, the vehicle disembarkation control unit 82 of the present application can provide feedback to the GPS module 90 based on the abnormality of the difference between the measured maximum working pressure value and the theoretical working pressure value. The GPS module 90 reports the vehicle abnormality alarm based on the feedback signal, and feeds back the abnormal signal to the customer to remind the customer to perform vehicle inspection and maintenance.

[0109] In this embodiment, when the working pressure error value is not within a reasonable preset range, it indicates that the hydraulic brake system is in an abnormal state. Specifically, when the maximum working pressure value is higher than the theoretical working pressure value and the error value is greater than 10%, the hydraulic brake system is judged to be abnormal, the computer alarms, and reminds the user to stop and check, but does not cut off the vehicle's driving function; the maximum working pressure value is higher than the theoretical working pressure value, and the error value is greater than 20%, the hydraulic brake system is judged to be seriously abnormal, the computer alarms, reminds the user to stop and check, and cuts off the vehicle's driving function and performs emergency braking; the maximum working pressure value is lower than the theoretical working pressure value, and the error value is greater than 10%, the hydraulic brake system is judged to be seriously abnormal, the computer alarms, reminds the user to stop and check, and cuts off the vehicle's driving function and performs emergency braking. Through the above-mentioned processing operations under abnormal conditions, the safety of the entire machine braking process is improved.

[0110] The third aspect of the present application provides a new energy engineering machinery, including the hydraulic brake system as described above. The engineering machinery adopts all the embodiments of the hydraulic brake system, and therefore has all the beneficial effects brought by the hydraulic brake system, which will not be described in detail here. Among them, the new energy engineering machinery can be an off-road tire crane, wherein the brake pedal 4 is installed on the upper vehicle assembly, and the axle brake is installed on the lower vehicle. The hydraulic braking system is connected by hydraulic pipelines, and the hydraulic pipeline distance between the upper vehicles is long and the hydraulic oil pressure transmission time is long. The electric proportional control valve 5 is installed on the lower vehicle assembly, and the electrical signal transmission rate is fast, the hydraulic pipeline distance is short, and the response speed is fast.

[0111] In the description of the present application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present application, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0112] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0113] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0114] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A hydraulic brake system for an engineering machine, the engineering machine comprising at least two actuators, characterized in that: The hydraulic brake system comprises: Brake pedal (4); A brake oil circuit, comprising oil supply circuits for supplying oil to the plurality of actuators respectively; An electric proportional regulating valve (5), arranged on each of the oil supply lines and used for regulating the working pressure of the actuator; A control module is electrically connected to the brake pedal (4) and the electric proportional control valve (5) and is configured as follows: Acquiring an input voltage signal of the brake pedal (4); Converting the input voltage signal into a control current signal; The opening degree of the electric proportional regulating valve (5) is controlled according to the control current signal.

2. The hydraulic brake system for construction machinery according to claim 1, characterized in that: The control module comprises a boarding control unit (81) and an alighting control unit (82) which are communicatively connected, the boarding control unit (81) being electrically connected to the brake pedal (4), the boarding control unit (81) being used to receive the input voltage signal sent by the brake pedal (4) and send it to the alighting control unit (82), and the alighting control unit (82) being used to convert the input voltage signal into the control current signal.

3. The hydraulic brake system for construction machinery according to claim 2, characterized in that: A connecting oil circuit is connected between the plurality of oil supply circuits, the connecting oil circuit is located between the actuator and the electric proportional control valve (5), a shuttle valve (61) and a pressure detection element (62) are provided on the connecting oil circuit, the pressure detection element (62) is used to detect the working pressure of the plurality of actuators, the shuttle valve (61) is used to obtain the maximum working pressure value among the plurality of working pressures and feed it back to the getting-off control unit (82), and the getting-off control unit (82) is further configured as follows: Obtaining a maximum working pressure value among the multiple working pressures; Comparing the maximum working pressure value with the theoretical working pressure value; Determine the working status of the hydraulic brake system based on the comparison results.

4. The hydraulic brake system for construction machinery according to claim 1, characterized in that: The hydraulic brake system further comprises an oil pump (1) and a filling valve group (2); the filling valve group (2) is arranged on the connecting oil circuit between the electric proportional control valve (5) and the oil pump (1); within a preset pressure range, the filling valve group (2) is used to conduct the connecting oil circuit between the electric proportional control valve (5) and the oil pump (1).

5. The hydraulic brake system for engineering machinery according to claim 4, characterized in that: The charging valve group (2) comprises a reversing valve (22) assembly and a charging valve (21) which are integrated into one body. The reversing valve (22) assembly comprises two parallel reversing valves (22). One side working oil ports of the two reversing valves (22) are respectively connected to the two electric proportional control valves (5). One side oil port of the charging valve (21) is connected to the other side working oil port of the reversing valve (22). The other side oil port of the charging valve (21) is switchably connected to the oil pump (1) or other oil circuits.

6. The hydraulic brake system for engineering machinery according to claim 4, characterized in that: The hydraulic brake system further comprises an accumulator (3), wherein the accumulator (3) is arranged on the connecting oil circuit between the charging valve (21) and the proportional regulating valve.

7. A braking control method for engineering machinery, characterized in that: Applied to the braking system according to any one of claims 1 to 6, the braking control method comprises the steps of: Acquiring an input voltage signal of the brake pedal (4); Converting the input voltage signal into a control current signal; controlling the opening of the electric proportional control valve (5) according to the control current signal; The working pressure of the corresponding actuator is adjusted according to the opening degree of the electric proportional control valve (5).

8. The brake control method for construction machinery according to claim 7, characterized in that: The step of converting the input voltage signal into a control current signal comprises: Acquiring the current operating condition of the engineering machinery; Selecting a corresponding braking curve according to the current operating condition of the engineering machinery; The input voltage signal is input into the braking curve to obtain the control current signal.

9. The brake control method for construction machinery according to claim 7, characterized in that: The braking control method further comprises the steps of: Calculating a theoretical working pressure value of the actuator according to a stepping angle of the brake pedal (4); Obtaining a maximum working pressure value among the working pressures of the plurality of actuators; Comparing the maximum working pressure value with the theoretical working pressure value; Determine the working status of the hydraulic brake system based on the comparison results.

10. The brake control method for construction machinery according to claim 9, characterized in that: The step of judging the working state of the hydraulic brake system according to the comparison result comprises: Acquire a working pressure error value according to the maximum working pressure value and the theoretical working pressure value; When the working pressure error value is in the range of -5% to 5%, it is judged that the hydraulic brake system is working normally; When the working pressure error value ranges from -10% to -5% or from 5% to 10%, it is determined that the hydraulic brake system is abnormal.

11. The brake control method for construction machinery according to claim 10, characterized in that: The step of judging the working state of the hydraulic brake system according to the comparison result also includes: When the maximum working pressure value is greater than the theoretical working pressure value, and the working pressure error value is greater than 10%, it is determined that the hydraulic brake system is abnormal and an alarm is issued; When the maximum working pressure value is greater than the theoretical working pressure value, and the working pressure error value is greater than 20%, the hydraulic brake system is judged to be abnormal and an alarm is sounded, and at the same time, the driving function of the engineering machinery is cut off and emergency braking is performed; When the maximum working pressure value is less than the theoretical working pressure value, and the working pressure error value is greater than 10%, the hydraulic brake system is judged to be abnormal and an alarm is issued, and at the same time, the driving function of the engineering machinery is cut off and emergency braking is performed.

12. A new energy engineering machinery, characterized in that: Comprising a braking system according to any one of claims 1 to 6.

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