WO2023226289A1 - Positive flow excavator, control method and control device therefor, and controller - Google Patents

Abstract

Embodiments of the present application provide a positive flow excavator, a control method and control device therefor, and a controller. The control method for a positive flow excavator comprises: obtaining the arm-in pilot pressure of the positive flow excavator; determining an action type of the positive flow excavator; under the condition that the action type is a preset action type, determining the allowable maximum secondary pressure of an arm-in electromagnetic valve, and determining a control current of the arm-in electromagnetic valve according to the maximum secondary pressure and the arm-in pilot pressure; under the condition that the action type is not the preset action type, determining the control current of the arm-in electromagnetic valve according to the arm-in pilot pressure; and outputting the control current to the arm-in electromagnetic valve so as to control an arm-in speed. According to the embodiments of the present application, different control policies can be set for an arm valve core according to different actions and different loads, the ground leveling performance of the positive flow excavator during a ground leveling operation is improved, and moreover, the oil consumption and the operation efficiency during an excavation operation are both considered.

Description

Positive flow excavator and control method, control device and controller thereof

Cross-references to related applications

This application claims the rights and interests of Chinese patent application 202210565260.8 submitted on May 23, 2022. The contents of this application are incorporated herein by reference.

Technical field

The present application relates to the technical field of excavator control, and specifically to a positive flow excavator and its control method, control device and controller.

Background technique

The excavator achieves ground leveling by lifting the boom (oil is fed into the large cavity of the boom) and the bucket rod is fed (oil is fed into the small cavity of the stick). Since the boom is lifted to overcome gravity, the pressure in the large cavity of the boom is higher than that in the small cavity of the stick. In order to ensure the controllability of level operations, a boom priority logic valve is usually added to the chamber pressure. When the boom and stick move at the same time, the boom priority logic valve limits the opening of the stick valve core to ensure the lifting speed of the boom. However, when the excavator is performing other actions such as excavation, the boom priority logic valve will still work, resulting in throttling loss and affecting the overall machine working efficiency and fuel efficiency. Therefore, there is an urgent need to propose a technical solution to solve the above technical problems in the prior art.

Application content

The purpose of the embodiments of the present application is to provide a positive flow excavator and its control method, control device and controller to solve the above technical problems in the prior art.

In order to achieve the above purpose, the first aspect of this application provides a control method for a positive flow excavator. The positive flow excavator includes a bucket, a boom, a bucket and a stick retraction solenoid valve. The control method includes: obtaining the positive flow excavator. The stick retraction pilot pressure of the flow excavator; determine the action type of the positive flow excavator; when the action type is the preset action type, determine the maximum secondary pressure allowed by the stick retraction solenoid valve, and determine the maximum secondary pressure according to the maximum secondary pressure. The secondary pressure and the stick retraction pilot pressure determine the control current of the stick retraction solenoid valve; when the action type is not the preset action type, the control current of the stick retraction solenoid valve is determined based on the stick retraction pilot pressure. ; and output the control current to the stick retraction solenoid valve to control the speed of the stick retraction; wherein the preset action types include one or more of the following: single stick retraction action; leveling action; and The bucket arm retracts and the boom arm lifts the bucket retracting compound action.

In the embodiment of the present application, the positive flow excavator also includes a turntable. Determining the action type of the positive flow excavator includes: obtaining the arm swing pilot pressure, rotation pilot pressure, boom lifting pilot pressure, boom Decrease the pilot pressure, bucket retraction pilot pressure and bucket swing-out pilot pressure; when the stick retraction pilot pressure is greater than or equal to the preset opening pressure and the stick swing-out pilot pressure, rotary pilot pressure, boom lift pilot pressure, When the boom lowering pilot pressure, bucket retracting pilot pressure and bucket swinging out pilot pressure are all less than the preset opening pressure, the action type is determined to be a single action of arm retracting; when the arm retracting pilot pressure and boom The situation when the lifting pilot pressure is greater than or equal to the preset opening pressure and the arm swing-out pilot pressure, the swing pilot pressure, the boom lowering pilot pressure, the bucket retraction pilot pressure, and the bucket swing-out pilot pressure are all less than the preset opening pressure , determine the action type is flat ground action; and when the stick retraction pilot pressure, boom lifting pilot pressure and bucket retraction pilot pressure are all greater than or equal to the preset opening pressure and the stick outward swing pilot pressure, rotation pilot pressure, When the boom lowering pilot pressure and the bucket swinging out pilot pressure are both less than the preset opening pressure, the action type is determined to be the compound action of arm retracting, boom lifting, and bucket retracting.

In the embodiment of this application, the positive flow excavator also includes a first main pump and a second main pump. Determining the maximum secondary pressure allowed by the arm retraction solenoid valve includes: when the action type is the arm retraction action. Next, obtain the pressure of the first main pump and the pressure of the second main pump; determine the maximum secondary pressure based on the pressure of the first main pump and the pressure of the second main pump; when the action type is leveling action, determine the leveling action The stage type; determine the maximum secondary pressure according to the stage type; when the action type is the compound action of stick retraction, boom lift, bucket retraction, obtain the boom lift pilot pressure and bucket retraction of the positive flow excavator pilot pressure; and determine the maximum secondary pressure based on the boom lifting pilot pressure and the bucket retracting pilot pressure; wherein the stage type is selected from any one of the initial stage, the intermediate stage and the end stage.

In the embodiment of the present application, determining the maximum secondary pressure based on the pressure of the first main pump and the pressure of the second main pump includes: determining the average value of the pressure of the first main pump and the pressure of the second main pump; and based on the average value Determine the maximum secondary pressure.

In the embodiment of the present application, determining the maximum secondary pressure based on the average value includes: determining the maximum secondary pressure based on the following formula:

Among them, Set_ArmInPilot_Max is the maximum secondary pressure, Aver_Pp1andPp2 is the average value, Set_ArmInPilot_Max1 is the first preset maximum secondary pressure, Set_ArmInPilot_Max2 is the second preset maximum secondary pressure, Pp1 is the first preset main pump pressure, and Pp2 is the second Preset main pump pressure.

In the embodiment of the present application, determining the stage type of the ground leveling action includes: determining the stage type as the end stage when the pressure of the first main pump and the pressure of the second main pump are both greater than or equal to the third preset main pump pressure. ; When the pressure of the first main pump and the pressure of the second main pump are both less than the third preset main pump pressure, determine whether the stick retraction pilot pressure is greater than or equal to the preset full-open pressure and determine the boom lifting pilot pressure. Whether the pressure is greater than or equal to the preset full-open pressure; when it is determined that the boom lifting pilot pressure and the stick retraction pilot pressure are both greater than or equal to the preset full-open pressure, determine the stage type as the initial stage; and when determining the dynamic When the arm lifting pilot pressure is less than the preset full-open pressure and the stick retraction pilot pressure is greater than or equal to the preset full-open pressure, the stage type is determined to be the intermediate stage.

In the embodiment of the present application, determining the maximum secondary pressure according to the stage type includes: when the stage type is the initial stage, determining the maximum secondary pressure as the third preset maximum secondary pressure; when the stage type is the intermediate stage In this case, the maximum secondary pressure is determined based on the boom lift pilot pressure; and in the case where the stage type is the end stage, the maximum secondary pressure is determined based on the pressure of the first main pump and the pressure of the second main pump.

In the embodiment of this application, the positive flow excavator also includes a first boom valve core. Determining the maximum secondary pressure according to the boom lifting pilot pressure includes: determining the maximum secondary pressure according to the following formula:

Among them, Set_ArmInPilot_Max is the maximum secondary pressure, Pilot_BoomUp is the boom lifting pilot pressure, Set_ArmInPilot_Max1 is the first preset maximum secondary pressure, Set_ArmInPilot_Max3 is the third preset maximum secondary pressure, and Pbu1 is required when the first boom valve core is opened. The minimum secondary pressure, Pbu2 is the minimum secondary pressure required when the first boom valve core is fully open.

In the embodiment of the present application, determining the maximum secondary pressure based on the boom lifting pilot pressure and the bucket retracting pilot pressure includes: determining the maximum value of the boom lifting pilot pressure and the bucket retracting pilot pressure; and determining based on the maximum value. Maximum secondary pressure.

In the embodiment of the present application, determining the maximum secondary pressure based on the maximum value includes: determining the maximum secondary pressure based on the following formula:

Among them, Set_ArmInPilot_Max is the maximum secondary pressure, BUandAIPilot_Max is the maximum value, Set_ArmInPilot_Max1 is the first preset maximum secondary pressure, Set_ArmInPilot_Max4 is the fourth preset maximum secondary pressure, Pba1 is the first preset pressure, and Pba2 is the second preset pressure.

In the embodiment of this application, determining the control current of the arm retraction solenoid valve based on the maximum secondary pressure and the arm retraction pilot pressure includes: when the arm retraction pilot pressure is less than or equal to the maximum secondary pressure, according to The stick retraction pilot pressure determines the control current of the stick retraction solenoid valve; and when the stick retraction pilot pressure is greater than the maximum secondary pressure, the control current of the stick retraction solenoid valve is determined based on the maximum secondary pressure.

In the embodiment of this application, the positive flow excavator also includes a first arm spool. Determining the control current of the arm retraction solenoid valve according to the arm retraction pilot pressure includes: determining the control current according to the following formula:

Among them, Set_Current is the control current, Pilot_ArmIn is the pilot pressure for arm retraction, Pilot_Min is the minimum secondary pressure required when the first arm valve core is opened, and Pilot_Max is the minimum secondary pressure required when the first arm valve core is fully opened. , Current_Max is the upper limit of the value range of the control current, and Current_Min is the lower limit of the value range of the control current.

In the embodiment of this application, determining the control current of the stick retraction solenoid valve according to the maximum secondary pressure includes: determining the control current according to the following formula:

Among them, Set_Current is the control current, Set_ArmInPilot_Max is the maximum secondary pressure, Pilot_Min is the minimum secondary pressure required when the first arm valve core is opened, Pilot_Max is the minimum secondary pressure required when the first arm valve core is fully opened, and Current_Max is the upper limit value of the value range of the control current, and Current_Min is the lower limit value of the value range of the control current.

A second aspect of the present application provides a controller configured to execute the control method for a positive flow excavator of the aforementioned embodiment.

The third aspect of the present application provides a control device for a positive flow excavator. The positive flow excavator includes a boom, a stick, a stick retraction solenoid valve, a turntable, a bucket, a first boom valve core, a first The control device of the stick spool, the first main pump and the second main pump includes: a stick retraction pilot pressure sensor configured to detect the stick retraction pilot pressure; a stick outward swing pilot pressure sensor configured to detect the stick retraction pilot pressure sensor. The arm swings out pilot pressure; the swing pilot pressure sensor is configured to detect the swing pilot pressure; the boom lift pilot pressure sensor is configured to detect the boom lift pilot pressure; the boom down pilot pressure sensor is configured to detect the boom Decrease pilot pressure; the bucket retraction pilot pressure sensor is configured to detect the bucket retraction pilot pressure; the bucket swing-out pilot pressure sensor is configured to detect the bucket swing-out pilot pressure; the first main pump pressure sensor is configured to detect the pressure of the first main pump; a second main pump pressure sensor configured to detect the pressure of the second main pump; and the controller of the aforementioned embodiment.

The fourth aspect of this application provides a positive flow excavator, including: a boom; a stick; a stick retraction solenoid valve; a turntable; a bucket; a first boom valve core; a first stick valve core; a first main a pump; a second main pump; and a control device for a positive flow excavator of the previous embodiment.

The embodiments of the present application can improve the ground leveling performance of a positive flow excavator during ground leveling operations through the aforementioned technical solutions while taking into account the fuel consumption and operating efficiency during excavation operations.

Other features and advantages of the embodiments of the present application will be described in detail in the following detailed description.

Description of the drawings

The drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the description. Together with the following specific implementation modes, they are used to explain the embodiments of the present application, but do not constitute a limitation to the embodiments of the present application. In the attached picture:

Figure 1 is a schematic flowchart of a control method 100 for a positive flow excavator according to an embodiment of the present application;

Figure 2 is a schematic structural diagram of a control device 200 for a positive flow excavator according to an embodiment of the present application;

Figure 3 is a schematic structural diagram of the positive flow excavator 300 according to the embodiment of the present application;

Figure 4 is a schematic structural diagram of a positive flow excavator control system based on bucket arm electronic control as an example of this application;

Figure 5 is a schematic flowchart of the positive flow excavator control method based on bucket rod electronic control in the example of this application;

Figure 6 is a schematic timing diagram of the arm retracting action judgment signal in an example of this application;

Figure 7 is a schematic timing diagram of the flat ground action judgment signal in an example of this application;

Figure 8 is a schematic timing diagram of the three-action composite judgment signal in this application example.

Figure 9 is a schematic diagram of a corresponding relationship between the control current of the arm retraction solenoid valve and the arm retraction pilot pressure in the example of this application;

Figure 10 is a schematic diagram of the relationship between the maximum secondary pressure allowed by the stick retraction solenoid valve and the average pressure of the main pump 205 and the main pump 206 in the example of this application;

Figure 11 is a schematic diagram of the flat ground action trajectory of the example of this application;

Figure 12 is a schematic diagram of the relationship between the maximum secondary pressure allowed by the stick retraction solenoid valve and the boom lifting pilot pressure in the example of this application; and

Figure 13 is a schematic diagram of the relationship between the maximum secondary pressure allowed by the arm retraction solenoid valve and the maximum value of the boom lifting pilot pressure and the bucket retraction pilot pressure in the example of this application.

Detailed ways

The specific implementation manners of the embodiments of the present application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific implementations described here are only used to illustrate and explain the embodiments of the present application, and are not used to limit the embodiments of the present application.

It should be noted that if there are directional instructions (such as up, down, left, right, front, back...) in the embodiments of the present application, the directional instructions are only used to explain the position of a certain posture (as shown in the accompanying drawings). The relative positional relationship, movement conditions, etc. between the components under the display). If the specific posture changes, the directional indication will also change accordingly.

In addition, if there are descriptions involving “first”, “second”, etc. in the embodiments of the present application, the descriptions of “first”, “second”, etc. are only for descriptive purposes and shall not be understood as indications or implications. Its relative importance or implicit indication of the number of technical features indicated. Therefore, features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the realization by those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that such a combination of technical solutions does not exist. , nor is it within the scope of protection required by this application.

As shown in Figure 1, in an embodiment of the present application, a control method 100 for a positive flow excavator is provided. The positive flow excavator includes a bucket, a boom, a bucket and a stick retraction solenoid valve for The control method 100 of the positive flow excavator includes the following steps:

Step S110: Obtain the arm retraction pilot pressure of the positive flow excavator.

Step S120: Determine the action type of the positive flow excavator.

Step S130: When the action type is the preset action type, determine the maximum secondary pressure allowed by the arm retraction solenoid valve, and determine the value of the arm retraction solenoid valve based on the maximum secondary pressure and the arm retraction pilot pressure. Control current.

Step S140: When the action type is not the preset action type, determine the control current of the arm retraction solenoid valve based on the arm retraction pilot pressure. as well as

Step S150: Output the control current to the arm retraction solenoid valve to control the speed of the arm retraction.

The preset action types include, for example, one or more of the following:

The action of closing the bucket inside the bucket;

flat ground maneuvers; and

The bucket arm retracts and the boom arm lifts the bucket retracting compound action. The compound action of bucket arm retraction and boom arm lifting bucket retraction is also called a three-action compound.

Further, the positive flow excavator also includes a turntable, for example. Correspondingly, determining the action type of the positive flow excavator, that is, step S120 includes, for example:

(a1) Obtain the arm swing-out pilot pressure, rotation pilot pressure, boom lifting pilot pressure, boom lowering pilot pressure, bucket retraction pilot pressure and bucket swing-out pilot pressure of the positive flow excavator.

(a2) When the arm retraction pilot pressure is greater than or equal to the preset opening pressure and the arm swing-out pilot pressure, rotation pilot pressure, boom lifting pilot pressure, boom lowering pilot pressure, bucket retraction pilot pressure and bucket retraction pilot pressure are When the swing-out pilot pressure is less than the preset opening pressure, the action type is determined to be the arm retracting action.

(a3) When the stick retraction pilot pressure and the boom lifting pilot pressure are both greater than or equal to the preset opening pressure and the stick outward swing pilot pressure, rotation pilot pressure, boom lowering pilot pressure, bucket retraction pilot pressure and shovel When the pilot pressure of the outer swing of the bucket is less than the preset opening pressure, the action type is determined to be a flat action. as well as

(a4) When the stick retraction pilot pressure, boom lifting pilot pressure and bucket retraction pilot pressure are all greater than or equal to the preset opening pressure and the stick outward swing pilot pressure, rotation pilot pressure, boom lowering pilot pressure and bucket retraction When the bucket swing-out pilot pressure is less than the preset opening pressure, the action type is determined to be the compound action of arm retraction, bucket retraction, and bucket retraction.

Specifically, the value range of the preset opening pressure is, for example, 5 bar to 7 bar, and specifically, the value is 5 bar.

Further, the positive flow excavator further includes a first main pump and a second main pump, for example. Correspondingly, determining the maximum secondary pressure allowed by the stick retraction solenoid valve in step S130 includes, for example, the following steps:

(b1) When the action type is the arm retracting action, obtain the pressure of the first main pump and the pressure of the second main pump.

(b2) Determine the maximum secondary pressure based on the pressure of the first main pump and the pressure of the second main pump.

(b3) When the action type is a flat action, determine the phase type of the flat action.

(b4) Determine the maximum secondary pressure according to the stage type.

(b5) When the action type is the compound action of arm retraction, boom lift, and bucket retraction, obtain the boom lift pilot pressure and bucket retraction pilot pressure of the positive flow excavator. as well as

(b6) Determine the maximum secondary pressure based on the boom lifting pilot pressure and the bucket retracting pilot pressure.

Wherein, the stage type is selected from any one of a starting stage, an intermediate stage and an ending stage, for example.

Specifically, the maximum secondary pressure is determined according to the pressure of the first main pump and the pressure of the second main pump, that is, step (b2) includes the following steps:

(b21) Determine the average value of the pressure of the first main pump and the pressure of the second main pump. as well as

(b22) Determine the maximum secondary pressure based on the average value.

Specifically, determining the maximum secondary pressure based on the average value, that is, step (b22) includes, for example:

Determine the maximum secondary pressure according to the following formula:

Among them, Set_ArmInPilot_Max is the maximum secondary pressure, Aver_Pp1andPp2 is the average value, Set_ArmInPilot_Max1 is the first preset maximum secondary pressure, Set_ArmInPilot_Max2 is the second preset maximum secondary pressure, Pp1 is the first preset main pump pressure, and Pp2 is the second Preset main pump pressure.

Specifically, the value range of the first preset maximum secondary pressure is, for example, 20 bar to 25 bar, and specifically, the value is 25 bar. The value range of the second preset maximum secondary pressure is, for example, 35 bar to 40 bar, and specifically, the value is 40 bar. The value range of the first preset main pump pressure is, for example, 15Mpa to 20Mpa, and specifically, the value is 15Mpa. The value range of the second preset main pump pressure is, for example, 25Mpa to 30Mpa, and specifically, the value is 25Mpa.

Specifically, determining the phase type of flat ground action, that is, step (b3), for example includes:

(b31) When the pressure of the first main pump and the pressure of the second main pump are both greater than or equal to the third preset main pump pressure, the stage type is determined to be the end stage.

(b32) When the pressure of the first main pump and the pressure of the second main pump are both less than the third preset main pump pressure, determine whether the stick retraction pilot pressure is greater than or equal to the preset full-open pressure and determine whether the boom Check whether the lifting pilot pressure is greater than or equal to the preset full-open pressure.

(b33) When it is determined that the boom lifting pilot pressure and the stick retracting pilot pressure are both greater than or equal to the preset full-open pressure, the stage type is determined to be the initial stage. as well as

(b34) When it is determined that the boom lifting pilot pressure is less than the preset full-open pressure and the stick retraction pilot pressure is greater than or equal to the preset full-open pressure, the stage type is determined to be the intermediate stage.

Specifically, the value range of the third preset main pump pressure is, for example, 15Mpa to 20Mpa, and specifically, the value is 15Mpa. The value range of the preset full-open pressure is, for example, 20bar to 25bar, and specifically, the value is 25bar.

Specifically, the maximum secondary pressure is determined according to the stage type, that is, step (b4) includes, for example:

(b41) When the stage type is the initial stage, the maximum secondary pressure is determined to be the third preset maximum secondary pressure.

(b42) When the stage type is the intermediate stage, the maximum secondary pressure is determined based on the boom lifting pilot pressure. as well as

(b43) When the stage type is the end stage, the maximum secondary pressure is determined based on the pressure of the first main pump and the pressure of the second main pump.

Further, the positive flow excavator further includes a first boom valve core, for example. Correspondingly, the maximum secondary pressure is determined according to the boom lifting pilot pressure, that is, step (b42) includes, for example:

Determine the maximum secondary pressure according to the following formula:

Among them, Set_ArmInPilot_Max is the maximum secondary pressure, Pilot_BoomUp is the boom lifting pilot pressure, Set_ArmInPilot_Max1 is the first preset maximum secondary pressure, Set_ArmInPilot_Max3 is the third preset maximum secondary pressure, and Pbu1 is required when the first boom valve core is opened. The minimum secondary pressure, Pbu2 is the minimum secondary pressure required when the first boom valve core is fully open.

Specifically, the value range of the first preset maximum secondary pressure is, for example, 20 bar to 25 bar, and specifically, the value is 25 bar. The value range of the third preset maximum secondary pressure is, for example, 10 bar to 15 bar, and specifically, the value is 12 bar. The value range of the minimum secondary pressure required when the first boom valve core is opened is, for example, 5 bar to 7 bar, and specifically, the value is 5 bar. The minimum secondary pressure required when the first boom valve core is fully opened ranges from 20 bar to 25 bar, for example, and specifically the value is 25 bar.

Specifically, the maximum secondary pressure is determined based on the boom lifting pilot pressure and the bucket retracting pilot pressure, that is, step (b6) includes the following steps:

(b61) Determine the maximum value of the boom lifting pilot pressure and bucket retracting pilot pressure. as well as

(b62) Determine the maximum secondary pressure based on the maximum value.

Specifically, the maximum secondary pressure is determined based on the maximum value, that is, step (b62) includes, for example:

Determine the maximum secondary pressure according to the following formula:

Among them, Set_ArmInPilot_Max is the maximum secondary pressure, BUandAIPilot_Max is the maximum value, Set_ArmInPilot_Max1 is the first preset maximum secondary pressure, Set_ArmInPilot_Max4 is the fourth preset maximum secondary pressure, Pba1 is the first preset pressure, and Pba2 is the second preset pressure.

Specifically, the value range of the first preset maximum secondary pressure is, for example, 20 bar to 25 bar, and specifically, the value range is 25 bar. The value range of the fourth preset maximum secondary pressure is, for example, 10 bar to 15 bar, and specifically, the value range is 12 bar. The value range of the first preset pressure is, for example, 5 bar to 7 bar, and specifically, the value is 5 bar. The value range of the second preset pressure is, for example, 20 bar to 25 bar, and specifically, the value is 25 bar.

Specifically, determining the control current of the arm retraction solenoid valve based on the maximum secondary pressure and the arm retraction pilot pressure in step S130 includes the following steps:

(c1) When the stick retraction pilot pressure is less than or equal to the maximum secondary pressure, determine the control current of the stick retraction solenoid valve based on the stick retraction pilot pressure. as well as

(c2) When the stick retraction pilot pressure is greater than the maximum secondary pressure, determine the control current of the stick retraction solenoid valve based on the maximum secondary pressure.

Further, the positive flow excavator also includes, for example, a first arm valve core, which determines the control current of the arm retraction solenoid valve according to the arm retraction pilot pressure, that is, step S140 includes, for example:

Determine the control current according to the following formula:

Among them, Set_Current is the control current, Pilot_ArmIn is the pilot pressure for arm retraction, Pilot_Min is the minimum secondary pressure required when the first arm valve core is opened, and Pilot_Max is the minimum secondary pressure required when the first arm valve core is fully opened. , Current_Max is the upper limit of the value range of the control current, and Current_Min is the lower limit of the value range of the control current.

Specifically, the control current of the stick retraction solenoid valve is determined according to the maximum secondary pressure, that is, step (c2) includes, for example:

Determine the control current according to the following formula:

Among them, Set_Current is the control current, Set_ArmInPilot_Max is the maximum secondary pressure, Pilot_Min is the minimum secondary pressure required when the first arm valve core is opened, Pilot_Max is the minimum secondary pressure required when the first arm valve core is fully opened, and Current_Max is the upper limit value of the value range of the control current, and Current_Min is the lower limit value of the value range of the control current.

Specifically, the value range of the minimum secondary pressure required when the first arm valve core is opened is, for example, 5 bar to 7 bar, and specifically, the value is 5 bar. The minimum secondary pressure required when the first arm valve core is fully opened ranges from, for example, 20 bar to 25 bar, with a specific value of, for example, 25 bar. The value range of the upper limit of the value range of the control current is, for example, 600 mA to 800 mA, and specifically, the value is 800 mA. The lower limit value of the value range of the control current ranges from 200 mA to 400 mA, for example, and specifically, the value is 250 mA.

In an embodiment of the present application, a controller is provided, which is configured, for example, to execute the control method 100 for a positive flow excavator according to any one of the preceding embodiments.

For specific functions and details of the control method 100 for a positive flow excavator, reference may be made to the relevant descriptions of the foregoing embodiments and will not be described again here.

Specifically, the controller may be, for example, an industrial computer, an embedded system, a microprocessor, a programmable logic device and other control devices.

More specifically, the controller is, for example, a vehicle controller of a positive flow excavator.

As shown in Figure 2, in the embodiment of the present application, a control device 200 for a positive flow excavator is provided. The positive flow excavator includes a boom, a stick, a stick retraction solenoid valve, a turntable, and a bucket. The first boom valve core, the first stick valve core, the first main pump and the second main pump. The control device 200 for a positive flow excavator includes: a controller 210, a stick retraction pilot pressure sensor 220, a bucket Rod swing-out pilot pressure sensor 230, rotary pilot pressure sensor 240, boom lift pilot pressure sensor 250, boom down pilot pressure sensor 260, bucket retraction pilot pressure sensor 270, bucket swing-out pilot pressure sensor 280, first Main pump pressure sensor 291 and second main pump pressure sensor 292 .

Wherein, the controller 210 is, for example, a controller according to any of the foregoing embodiments. For the specific functions and details of the controller 210, please refer to the relevant descriptions of the foregoing embodiments, and will not be described again here.

The arm retraction pilot pressure sensor 220 is configured, for example, to detect the arm retraction pilot pressure.

The arm swing-out pilot pressure sensor 230 is configured, for example, to detect the arm swing-out pilot pressure.

Swing pilot pressure sensor 240 is configured, for example, to detect swing pilot pressure.

Boom lift pilot pressure sensor 250 is configured, for example, to detect boom lift pilot pressure.

The boom down pilot pressure sensor 260 is configured to detect the boom down pilot pressure, for example.

The bucket retraction pilot pressure sensor 270 is configured, for example, to detect the bucket retraction pilot pressure.

Bucket pitch-out pilot pressure sensor 280 is configured, for example, to detect bucket pitch-out pilot pressure.

The first main pump pressure sensor 291 is configured to detect the pressure of the first main pump, for example.

The second main pump pressure sensor 292 is configured, for example, to detect the pressure of the second main pump.

In the embodiment of the present application, a positive flow excavator 300 is provided, including: a control device 310, a boom 320, a stick 330, a stick retraction solenoid valve 340, a turntable 350, a bucket 360, and a first boom valve. core 370, the first stick valve core 380, the first main pump 391 and the second main pump 392.

Wherein, the control device 310 is, for example, the control device 200 for a positive flow excavator according to any of the foregoing embodiments. For specific functions and details of the control device 310, reference may be made to the relevant descriptions of the foregoing embodiments and will not be described again here.

The control method 100 for a positive flow excavator, the control device 200 for a positive flow excavator, and the positive flow excavator 300 according to the embodiment of the present application will be described in detail below with reference to a specific example. The specific content of the example of the present application is as follows:

In order to achieve both controllability and fuel efficiency for operations such as leveling, as shown in Figure 4, this application example provides a positive flow excavator control system and control method based on bucket arm electronic control. The control system mainly includes a left handle 101, Left walking pedal 102, right walking pedal 103, right handle 104, pilot pressure sensor group 200 (200-1 is the pilot pressure sensor for stick adduction, 200-2 is the pilot pressure sensor for stick outward swing, and 200-3 is the rotation Pilot pressure sensor, 200-4 is the left traveling pilot pressure sensor, 200-5 is the right traveling pilot pressure sensor, 200-6 is the boom lifting pilot pressure sensor, 200-7 is the boom lowering pilot pressure sensor, 200-8 is the Bucket retraction pilot pressure sensor, 200-9 is the bucket swing-out pilot pressure sensor), main pump pressure sensor 201, main pump pressure sensor 202, main pump solenoid valve 203, main pump solenoid valve 204, main pump 205, main pump Pump 206, boom cylinder 301, stick cylinder 302, stick 2 valve core 303, stick 1 valve core 304, boom 1 valve core 305, boom 2 valve core 306, display 401, controller 402, engine control 403, engine 404, stick retracting solenoid valve 501, stick swinging out solenoid valve 502.

The positive flow excavator control system based on arm electronic control in the example of this application cancels the 307 boom priority logic valve and adds the arm retraction solenoid valve 501 and the arm swing out solenoid valve 502. The controller collects the pilot pressure of the control handle and the pressure of the main pump, identifies different actions and different loads, and sets different control strategies for the stick valve core according to different actions and loads, so as to ensure smooth operation such as flat ground. While improving the controllability, taking into account fuel consumption and operating efficiency, the execution process of the positive flow excavator control method based on arm electronic control in the example of this application will be explained below with reference to the accompanying drawings.

1. Action recognition

As shown in Figure 5, action recognition is first performed. Specifically, the controller 402 collects the signal of the pilot pressure sensor group 200 and identifies that the current action type is a single action of the arm, that is, a single action of the arm retracting, a leveling action, The three-action compound action means that the bucket arm is retracted, the boom arm is retracted, and the bucket is retracted. It is also an action other than the three actions mentioned above. The specific judgment rules are as follows:

1. The action of closing the bucket within the bucket:

As shown in Figure 6, which is a timing diagram of the stick retraction action judgment signal, the controller 402 collects the signals of the pilot pressure sensor group 200, specifically the signals corresponding to the two control handles, namely the left handle 101 and the right handle 104. The signal of the pilot pressure sensor, usually the pilot pressure range is 0-40bar, the opening pressure of the valve core is 5-7bar, the pilot pressure is 0 when the handle is not operated, so when the stick is retracted, the pilot pressure is greater than or equal to 5bar , and other pilot pressures corresponding to the control handle (including stick outward swing pilot pressure, rotary pilot pressure, boom lifting pilot pressure, boom lowering pilot pressure, bucket retracting pilot pressure and bucket swinging out pilot pressure) are all less than 5bar, then the controller 402 determines the current action type of the excavator as the arm retracting action.

2. Flat ground action

The operator realizes the leveling action by lifting the boom and retracting the stick at the same time. Figure 7 shows the timing diagram of the leveling action judgment signal. When the stick retraction pilot pressure is greater than or equal to 5bar, the boom lifting pilot pressure is greater than or equal to 5bar. is equal to 5bar, and other pilot pressures corresponding to the control handle (including stick outward swing pilot pressure, rotary pilot pressure, boom lowering pilot pressure, bucket retraction pilot pressure and bucket outward swing pilot pressure) are all less than 5bar, then control The detector 402 determines the current action type of the excavator as a ground leveling action.

3. Three-movement compound

Figure 8 shows the three-action composite state judgment signal timing diagram. When the stick retraction pilot pressure is greater than or equal to 5bar, the boom lifting pilot pressure is greater than or equal to 5bar, and the bucket retraction pilot pressure is greater than or equal to 5bar, And other pilot pressures corresponding to the control handle (including stick outward swing pilot pressure, rotation pilot pressure, boom lowering pilot pressure and bucket swing out pilot pressure) are all less than 5 bar, then the controller 402 will determine the current action type of the excavator It is the compound action of bucket arm retracting and boom arm lifting, which is also a three-action compound state.

4. Other actions

When the corresponding judgment conditions of the above three actions 1-3 are not satisfied, the controller 402 judges the current action type of the excavator as other actions, that is, all actions except the above three action types are other actions.

2. Stick retraction spool control

In order to ensure controllability while taking into account fuel consumption and operating efficiency, this application example adopts different control strategies for different action types and different loads. The specific control strategies are as follows:

1. The action of closing in the bucket rod

As shown in Figure 9, the conventional control strategy is to directly determine the control current of the stick retraction solenoid valve based on the stick retraction pilot pressure, that is, the control current output by the controller 402 to the stick retraction solenoid valve 501 is consistent with the stick retraction solenoid valve 501. Adduction pilot pressure has a linear relationship. The formula corresponding to the conventional control strategy is as follows:

Formula 1:

Among them, Set_Current is the control current output to the arm retraction solenoid valve 501, Pilot_ArmIn is the arm retraction pilot pressure, Pilot_Min is the minimum secondary pressure required when the arm 2 valve core 303 is opened, and Pilot_Max is the arm 2 valve core. The minimum secondary pressure required when 303 is fully open. The value range of Pilot_Min is 5bar-7bar, and the specific value is, for example, 5bar. The value range of Pilot_Max is 20bar-25bar, and the specific value is, for example, 25bar.

The initial stage of stick retraction is the work of gravity. If the opening of valve core 303 of stick 2 is too large, a vacuum phenomenon will occur due to insufficient flow. If the opening is too small, throttling loss will occur. In order to avoid this problem, in the example of this application, the controller 402 collects the pressure of the main pump 205 and the pressure of the main pump 206 through 201 and 202 while collecting the arm retraction pilot pressure. As shown in Figure 10, when the main pump When the average pressure of 205 and main pump 206 is less than 15Mpa, the controller 402 determines the current status of the excavator as a light load operation. In order to avoid the suction phenomenon, the controller 402 retracts the arm to the maximum secondary pressure allowed by the solenoid valve 501 Set to Set_ArmInPilot_Max1, Set_ArmInPilot_Max1 usually takes a value of 20bar-25bar, for example, it can take 25bar. When the average pressure of the main pump 205 and the main pump 206 is greater than or equal to 15Mpa, the controller 402 determines the current state as a heavy load action. In order to reduce the throttling loss, the controller 402 allows the stick retraction solenoid valve 501 to output the maximum secondary pressure at When the average pressure of the main pump 205 and the main pump 206 is within 15Mpa-25Mpa, it has a linear relationship with the average pressure of the main pump 205 and the main pump 206. When the average pressure of the main pump 205 and the main pump 206 is greater than or equal to 25Mpa, the controller 402 The maximum secondary pressure allowed by the stick retraction solenoid valve 501 is set to Set_ArmInPilot_Max2. The value range of Set_ArmInPilot_Max2 is, for example, 35 bar to 40 bar, and the specific value is, for example, 40 bar.

The specific process for calculating the control current of the stick retraction solenoid valve 501 is as follows:

(1) Based on the average pressure of the main pump 205 and the main pump 206, calculate the maximum secondary pressure allowed to be set by the stick retraction solenoid valve 501, specifically as formula 2.

Formula 2:

Among them, Set_ArmInPilot_Max is the maximum secondary pressure allowed to be set for the stick retraction solenoid valve 501, Aver_Pp1andPp2 is the average of the pilot pressure of the main pump 205 and the pilot pressure of the main pump 206, and the value range of Set_ArmInPilot_Max1 is, for example, 20bar to 25bar. The specific value is, for example, 25bar. The value range of Set_ArmInPilot_Max2 is, for example, 35bar to 40bar, and the specific value is, for example, 40bar.

(2) When the measured arm retraction pilot pressure is less than or equal to the maximum allowable secondary pressure, which is the Set_ArmInPilot_Max determined in the previous step (1), the control current of the arm retraction solenoid valve 501 is as shown in Figure 9 Set the conventional control strategy.

(3) When the measured arm retraction pilot pressure is greater than the maximum allowable secondary pressure Set_ArmInPilot_Max, limit the control current of the arm retraction solenoid valve 501 to the maximum allowable setting according to the conventional control strategy shown in Figure 9 The control current corresponding to the secondary pressure Set_ArmInPilot_Max.

That is to say, if the arm retraction pilot pressure is less than or equal to the determined maximum secondary pressure Set_ArmInPilot_Max, then according to the conventional control strategy shown in Figure 9, the arm retraction pilot pressure corresponding to the control that needs to be output to the arm retraction solenoid valve is determined. Current, if the stick retraction pilot pressure is greater than the determined maximum secondary pressure Set_ArmInPilot_Max, combined with Figure 9 to determine the value of the stick retraction pilot pressure is the maximum secondary pressure Set_ArmInPilot_Max, the corresponding need to be output to the control of the stick retraction solenoid valve current.

Through the above method, the cavitation phenomenon at light load can be avoided, and the throttling loss at heavy load can be effectively reduced.

In summary, the control strategy for the single action of arm retraction is: first determine the maximum secondary pressure Set_ArmInPilot_Max allowed by the arm retraction solenoid valve 501 based on the average pressure of the two main pumps, and then determine the maximum secondary pressure Set_ArmInPilot_Max allowed by the arm retraction solenoid valve 501 based on the average pressure of the two main pumps. The pilot pressure and the determined maximum secondary pressure Set_ArmInPilot_Max allowed by the arm retraction solenoid valve 501 and the corresponding relationship between the arm retraction pilot pressure and the arm retraction solenoid valve set current in the conventional control strategy as shown in Figure 9 Determine the control current output to the stick retraction solenoid valve 501.

2. Flat ground action

The operator realizes the ground leveling action by lifting the boom and retracting the stick at the same time, as shown in Figure 11. The vertical axis in Figure 11 represents the height of the bucket tooth tip relative to the target working surface during leveling operations. If it is a positive value, is above the target working surface, if it is a negative value, it is below the target working surface. The effect of the ideal leveling action is that as the working device is operated, the bucket tip moves at the height of the target working surface. In order to improve the controllability of the leveling action and Taking into account fuel economy, the flat ground action process is divided into three stages for control. Compared with the control strategies of the flat ground action and the arm retraction single action, the only difference lies in the setting strategy of the maximum secondary pressure Set_ArmInPilot_Max that the arm retraction solenoid valve 501 is allowed to output. specifically:

(1)Initial stage

If the boom lifting pilot pressure and the bucket arm retracting pilot pressure are both greater than or equal to the preset full-open pressure such as 25bar, the arm swinging out pilot pressure, the swing pilot pressure, the boom lowering pilot pressure, the bucket retracting pilot pressure and the bucket If the bucket swing-out pilot pressure is both less than the preset opening pressure, such as 5 bar, and the pressures of the main pump 205 and the main pump 206 are both less than 15 MPa, it is judged to be the initial stage of the leveling action.

In the initial stage, if the valve core of stick 2 is opened too fast, the tip of the bucket will be directly hit on the target working surface, causing the trajectory of the tip of the bucket to be lower than the target working surface in leveling operations, resulting in a nodding phenomenon. If stick 2 If the valve core is opened too slowly, the bucket tip will directly leave the target working surface, causing the bucket tip trajectory to be higher than the target working surface for flat ground operations, resulting in bagging. Therefore, in order to ensure that the boom lifting speed is coordinated with the bucket arm retracting speed , when the controller 402 determines that the current operation intention is a flat ground action, in the initial stage, the maximum secondary pressure Set_ArmInPilot_Max allowed to be output by the stick retraction solenoid valve 501 will be directly set to Set_ArmInPilot_Max3. The value range of Set_ArmInPilot_Max3 is usually 10-15bar. The specific value is, for example, 12 bar, and the specific parameter value setting can be set according to the specific flat ground action effect, for example.

(2) Intermediate stage

If the arm retraction pilot pressure is greater than or equal to the preset full-open pressure, such as 25bar, and the boom lifting pilot pressure is greater than or equal to the preset opening pressure and less than the preset full-open pressure, the arm swing-out pilot pressure, rotary pilot pressure, and dynamic If the arm lowering pilot pressure, bucket retracting pilot pressure, and bucket swinging out pilot pressure are all less than the preset opening pressure, and the pressures of the main pump 205 and the main pump 206 are both less than 15 MPa, it is determined to be the intermediate stage of the ground leveling action.

As the ground leveling action progresses, in the intermediate stage, in order to ensure that the bucket tooth tips do not deviate from the target working surface, it is necessary to gradually reduce the boom lifting speed and speed up the bucket arm retraction speed. The boom lifting speed is reduced by the operator. The opening of the arm control handle is controlled, and the speed of the stick retraction is controlled by gradually increasing the current of the stick retraction solenoid valve 501, thereby ensuring a longer flat ground distance.

As shown in Figure 12, when the boom lifting pilot pressure is greater than or equal to 25 bar, the maximum secondary pressure Set_ArmInPilot_Max allowed to be output by the stick retraction solenoid valve 501 is directly set to Set_ArmInPilot_Max3. When the actual measured value of the boom lift pilot pressure is in the range of less than 25 bar and greater than or equal to 5 bar, the maximum secondary pressure Set_ArmInPilot_Max allowed to be output by the stick retraction solenoid valve 501 is inversely proportional to the boom lift pilot pressure. When the boom lifting pilot pressure is less than 5bar, the value is Set_ArmInPilot_Max1. Specifically as formula 3:

Formula 3:

Among them, Set_ArmInPilot_Max is the maximum secondary pressure allowed to be output by the stick retraction solenoid valve 501, and Pilot_BoomUp is the boom lifting pilot pressure. The value range of Set_ArmInPilot_Max1 is, for example, 20bar to 25bar, and the specific value is, for example, 25bar. The value range of Set_ArmInPilot_Max3 is usually between 10-15bar, and the specific value is, for example, 12bar.

(3) Ending stage

If the boom lifting pilot pressure and the stick retracting pilot pressure are both greater than or equal to the preset opening pressure such as 5bar, the stick outward swing pilot pressure, the swing pilot pressure, the boom lowering pilot pressure, the bucket retracting pilot pressure and the bucket If the swing-out pilot pressure is both less than the preset opening pressure, and the pressures of the main pump 205 and the main pump 206 are both greater than or equal to 15 MPa, it is determined to be the end stage of the leveling action.

In the end stage, in order to reduce fuel consumption, the maximum secondary pressure Set_ArmInPilot_Max allowed to be output by the arm retraction solenoid valve 501 is set in the same way as during the arm retraction single action. The controller 402 determines it based on the average pressure of the two main pumps. Corresponding Set_ArmInPilot_Max. For details, please refer to the foregoing descriptions and will not be repeated here.

For the three stages of leveling action, after determining the maximum secondary pressure Set_ArmInPilot_Max that the arm retraction solenoid valve 501 is allowed to output, the controller 402 will determine the maximum secondary pressure Set_ArmInPilot_Max and the arm retraction pilot pressure based on the determined stage. To determine the control current output to the arm retraction solenoid valve 501, the controller 402 will determine the control current output to the arm retraction solenoid valve 501 based on the maximum secondary pressure Set_ArmInPilot_Max determined at this stage and the arm retraction pilot pressure. The specific method is the same as the action of closing in the bucket, so I won’t go into details here. You can refer to the description in the previous part.

Through the control of the above three stages of flat ground action, the controllability in the initial stage, the flat ground distance in the intermediate stage can be ensured, and the fuel economy in the final stage can be taken into consideration.

3. Three-movement compound

In the three-action composite state, in order to ensure the coordination of the boom lifting speed, bucket retraction speed and bucket rod retraction speed, as shown in Figure 13, the maximum of the boom lifting pilot pressure and bucket retraction pilot pressure is When the value is greater than or equal to 25bar, the maximum secondary pressure Set_ArmInPilot_Max output by the stick retraction solenoid valve 501 is set to Set_ArmInPilot_Max4. The value range of Set_ArmInPilot_Max4 is 10-15bar. For example, the value is 12bar. When the maximum value of the boom lifting pilot pressure and the bucket retracting pilot pressure is less than 25bar and greater than or equal to 5bar, the maximum secondary pressure Set_ArmInPilot_Max allowed to be output by the stick retracting solenoid valve 501 is the same as the boom lifting pilot pressure and the bucket retracting pilot pressure. Bucket retraction pilot pressure is inversely proportional to the maximum value of the two. When the maximum value of the boom lifting pilot pressure and the bucket retracting pilot pressure is less than 5 bar, the value of the maximum secondary pressure Set_ArmInPilot_Max allowed to be output by the stick retracting solenoid valve 501 is Set_ArmInPilot_Max1, and the value range of Set_ArmInPilot_Max1 is as follows: It is 20bar to 25bar, and the specific value is 25bar, for example.

Among them, Set_ArmInPilot_Max is the maximum secondary pressure allowed to be output by the arm retraction solenoid valve 501, and Max is the maximum value of the boom lifting pilot pressure and the bucket retraction pilot pressure.

4. Other actions

When it is determined that the current action of the excavator is other actions, the controller 402 does not limit the maximum secondary pressure allowed to be output by the stick retraction solenoid valve 501. The controller 402 directly calculates the required output to the bucket according to the conventional control strategy shown in Figure 9. The control current of the rod adduction solenoid valve 501.

To sum up, the embodiment of the present application uses an electronically controlled valve core through the bucket arm, and collects the pilot pressure of the control handle and the pressure of the main pump to identify different action types and different load conditions, and according to different action types and loads According to the situation, different control strategies are set for the stick valve core, and the control current output to the stick retraction solenoid valve that controls the opening size of the stick valve core is ensured to ensure the controllability of various actions including flat ground movements. At the same time, it can take into account fuel consumption and operating efficiency.

Those skilled in the art will understand that embodiments of the present application may be provided as methods, systems, or computer program products. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment that combines software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each process and/or block in the flowchart illustrations and/or block diagrams, and combinations of processes and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions executed by the processor of the computer or other programmable data processing device produce a use A device for realizing the functions specified in one process or multiple processes of the flowchart and/or one block or multiple blocks of the block diagram.

These computer program instructions may also be stored in a computer-readable memory that causes a computer or other programmable data processing apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including the instruction means, the instructions The device implements the functions specified in a process or processes of the flowchart and/or a block or blocks of the block diagram.

These computer program instructions may also be loaded onto a computer or other programmable data processing device, causing a series of operating steps to be performed on the computer or other programmable device to produce computer-implemented processing, thereby executing on the computer or other programmable device. Instructions provide steps for implementing the functions specified in a process or processes of a flowchart diagram and/or a block or blocks of a block diagram.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

Memory may include non-volatile memory in computer-readable media, random access memory (RAM) and/or non-volatile memory in the form of read-only memory (ROM) or flash memory (flash RAM). Memory is an example of a computer-readable medium.

Computer-readable media includes both persistent and non-volatile, removable and non-removable media that can be implemented by any method or technology for storage of information. Information may be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), and read-only memory. (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, Magnetic tape cassettes, tape magnetic disk storage or other magnetic storage devices or any other non-transmission medium can be used to store information that can be accessed by a computing device. As defined in this article, computer-readable media does not include transitory media, such as modulated data signals and carrier waves.

It should also be noted that the terms "comprises," "comprises," or any other variation thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements not only includes those elements, but also includes Other elements are not expressly listed or are inherent to the process, method, article or equipment. Without further limitation, an element qualified by the statement "comprises a..." does not exclude the presence of additional identical elements in the process, method, good, or device that includes the element.

The above are only examples of the present application and are not used to limit the present application. To those skilled in the art, various modifications and variations may be made to this application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of this application shall be included in the scope of the claims of this application.

Claims (16)

1. A control method for a positive flow excavator. The positive flow excavator includes a bucket, a boom, a bucket and a stick retraction solenoid valve. The control method includes:

   Obtain the arm retraction pilot pressure of the positive flow excavator;

   Determine the action type of the positive flow excavator;

   When the action type is a preset action type, determine the maximum secondary pressure allowed by the arm retraction solenoid valve, and determine the arm retraction pilot pressure based on the maximum secondary pressure and the arm retraction pilot pressure. The control current of the stick retraction solenoid valve;

   When the action type is not the preset action type, determine the control current of the arm retraction solenoid valve according to the arm retraction pilot pressure; and

   Output the control current to the arm retraction solenoid valve to control the speed of the arm retraction;

   Wherein, the preset action types include one or more of the following:

   The action of closing the bucket inside the bucket;

   flat ground maneuvers; and

   The bucket arm retracts and the boom arm lifts the bucket retracting compound action.
2. The control method according to claim 1, wherein the positive flow excavator further includes a turntable, and determining the action type of the positive flow excavator includes:

   Obtain the arm swing-out pilot pressure, rotation pilot pressure, boom lifting pilot pressure, boom lowering pilot pressure, bucket retraction pilot pressure and bucket swing-out pilot pressure of the positive flow excavator;

   When the arm retracting pilot pressure is greater than or equal to the preset opening pressure and the arm swinging out pilot pressure, the swing pilot pressure, the boom lifting pilot pressure, the boom lowering pilot pressure, the When the bucket retraction pilot pressure and the bucket swing-out pilot pressure are both less than the preset opening pressure, the action type is determined to be the arm retraction single action;

   When the arm retracting pilot pressure and the boom lifting pilot pressure are both greater than or equal to the preset opening pressure and the arm swinging out pilot pressure, the swing pilot pressure, the boom lowering pilot pressure, all When the bucket retraction pilot pressure and the bucket swing-out pilot pressure are both less than the preset opening pressure, the action type is determined to be the leveling action; and

   When the arm retraction pilot pressure, the boom lifting pilot pressure and the bucket retraction pilot pressure are all greater than or equal to the preset opening pressure and the arm swing-out pilot pressure, the rotary pilot pressure When the pressure, the boom lowering pilot pressure and the bucket swinging out pilot pressure are all less than the preset opening pressure, the action type is determined to be the arm retracting, boom lifting, bucket retracting compound action.
3. The control method according to claim 2, wherein the positive flow excavator further includes a first main pump and a second main pump, and determining the maximum secondary pressure allowed by the stick retraction solenoid valve includes:

   When the action type is the arm retracting action, obtain the pressure of the first main pump and the pressure of the second main pump;

   Determine the maximum secondary pressure based on the pressure of the first main pump and the pressure of the second main pump;

   When the action type is the flat ground action, determine the phase type of the flat ground action;

   Determine the maximum secondary pressure according to the stage type;

   When the action type is the compound action of arm retracting, boom lifting, and bucket retracting, obtain the boom lifting pilot pressure and bucket retracting pilot pressure of the positive flow excavator; and

   The maximum secondary pressure is determined based on the boom lifting pilot pressure and the bucket retracting pilot pressure;

   Wherein, the stage type is selected from any one of a starting stage, an intermediate stage and an ending stage.
4. The control method according to claim 3, wherein determining the maximum secondary pressure according to the pressure of the first main pump and the pressure of the second main pump includes:

   determining an average of the pressure of the first main pump and the pressure of the second main pump; and

   The maximum secondary pressure is determined based on the average value.
5. The control method according to claim 4, wherein determining the maximum secondary pressure according to the average value includes:

   The maximum secondary pressure is determined according to the following formula:

   

   Among them, Set_ArmInPilot_Max is the maximum secondary pressure, Aver_Pp1andPp2 is the average value, Set_ArmInPilot_Max1 is the first preset maximum secondary pressure, Set_ArmInPilot_Max2 is the second preset maximum secondary pressure, and Pp1 is the first preset main pump pressure, Pp2 is the second preset main pump pressure.
6. The control method according to claim 3, wherein the determining the phase type of the flat ground action includes:

   In the case where the pressure of the first main pump and the pressure of the second main pump are both greater than or equal to the third preset main pump pressure, determine the stage type to be the end stage;

   When the pressure of the first main pump and the pressure of the second main pump are both less than the third preset main pump pressure, it is determined whether the stick retraction pilot pressure is greater than or equal to the preset pressure. Full opening pressure and determining whether the boom lifting pilot pressure is greater than or equal to the preset full opening pressure;

   When it is determined that the boom lifting pilot pressure and the stick retracting pilot pressure are both greater than or equal to the preset full opening pressure, the stage type is determined to be the initial stage; and

   When it is determined that the boom lifting pilot pressure is less than the preset full-open pressure and the stick retraction pilot pressure is greater than or equal to the preset full-open pressure, the stage type is determined to be the intermediate stage. .
7. The control method according to claim 3, wherein determining the maximum secondary pressure according to the stage type includes:

   In the case where the stage type is the initial stage, determining the maximum secondary pressure to be the third preset maximum secondary pressure;

   In the case where the stage type is the intermediate stage, the maximum secondary pressure is determined based on the boom lift pilot pressure; and

   In the case where the stage type is the end stage, the maximum secondary pressure is determined based on the pressure of the first main pump and the pressure of the second main pump.
8. The control method according to claim 7, wherein the positive flow excavator further includes a first boom valve core, and determining the maximum secondary pressure according to the boom lifting pilot pressure includes:

   The maximum secondary pressure is determined according to the following formula:

   

   Among them, Set_ArmInPilot_Max is the maximum secondary pressure, Pilot_BoomUp is the boom lifting pilot pressure, Set_ArmInPilot_Max1 is the first preset maximum secondary pressure, Set_ArmInPilot_Max3 is the third preset maximum secondary pressure, and Pbu1 is the third preset maximum secondary pressure. The minimum secondary pressure required when the first boom valve core is opened, Pbu2 is the minimum secondary pressure required when the first boom valve core is fully opened.
9. The control method according to claim 3, wherein determining the maximum secondary pressure based on the boom lifting pilot pressure and the bucket retraction pilot pressure includes:

   Determining the maximum value of the boom lift pilot pressure and the bucket retraction pilot pressure; and

   The maximum secondary pressure is determined based on the maximum value.
10. The control method according to claim 9, wherein determining the maximum secondary pressure according to the maximum value includes:

    The maximum secondary pressure is determined according to the following formula:

    

    Among them, Set_ArmInPilot_Max is the maximum secondary pressure, BUandAIPilot_Max is the maximum value, Set_ArmInPilot_Max1 is the first preset maximum secondary pressure, Set_ArmInPilot_Max4 is the fourth preset maximum secondary pressure, Pba1 is the first preset pressure, and Pba2 is Second preset pressure.
11. The control method according to claim 1, wherein determining the control current of the arm retraction solenoid valve based on the maximum secondary pressure and the arm retraction pilot pressure includes:

    When the arm retraction pilot pressure is less than or equal to the maximum secondary pressure, determine the control current of the arm retraction solenoid valve according to the arm retraction pilot pressure; and

    When the arm retraction pilot pressure is greater than the maximum secondary pressure, the control current of the arm retraction solenoid valve is determined based on the maximum secondary pressure.
12. The control method according to claim 11, wherein the positive flow excavator further includes a first arm valve core, and determining the control current of the arm retraction solenoid valve according to the arm retraction pilot pressure includes:

    The control current is determined according to the following formula:

    

    Among them, Set_Current is the control current, Pilot_ArmIn is the pilot arm retraction pressure, Pilot_Min is the minimum secondary pressure required when the first arm valve core is opened, and Pilot_Max is the full pressure of the first arm valve core. The minimum secondary pressure required when opening, Current_Max is the upper limit of the value range of the control current, and Current_Min is the lower limit of the value range of the control current.
13. The control method according to claim 12, wherein determining the control current of the stick retraction solenoid valve according to the maximum secondary pressure includes:

    The control current is determined according to the following formula:

    

    Among them, Set_Current is the control current, Set_ArmInPilot_Max is the maximum secondary pressure, Pilot_Min is the minimum secondary pressure required when the first arm valve core is opened, and Pilot_Max is when the first arm valve core is fully opened. The required minimum secondary pressure, Current_Max is the upper limit of the value range of the control current, and Current_Min is the lower limit of the value range of the control current.
14. A controller configured to perform the control method for a positive flow excavator according to any one of claims 1 to 13.
15. A control device for a positive flow excavator. The positive flow excavator includes a boom, a bucket rod, a bucket rod retracting solenoid valve, a turntable, a bucket, a first boom valve core, and a first bucket rod valve core. , the first main pump and the second main pump, the control device includes:

    The stick retraction pilot pressure sensor is configured to detect the stick retraction pilot pressure;

    The arm swing-out pilot pressure sensor is configured to detect the arm swing-out pilot pressure;

    a rotary pilot pressure sensor configured to detect rotary pilot pressure;

    a boom lift pilot pressure sensor configured to detect boom lift pilot pressure;

    a boom down pilot pressure sensor configured to detect boom down pilot pressure;

    a bucket retraction pilot pressure sensor configured to detect bucket retraction pilot pressure;

    The bucket swing-out pilot pressure sensor is configured to detect the bucket swing-out pilot pressure;

    a first main pump pressure sensor configured to detect the pressure of the first main pump;

    A second main pump pressure sensor configured to detect the pressure of the second main pump; and

    The controller of claim 14.
16. A positive flow excavator including:

    Boom;

    Stick;

    Stick retraction solenoid valve;

    turntable;

    Bucket;

    first boom valve core;

    The first stick valve core;

    first main pump;

    second main pump; and

    The control device for a positive flow excavator according to claim 15.

Images