CN114411863A

CN114411863A - Positive flow excavator and control method, control device and controller thereof

Info

Publication number: CN114411863A
Application number: CN202111650219.2A
Authority: CN
Inventors: 高见厂; 李帆; 吴元峰; 魏学平; 邓付军
Original assignee: Zoomlion Earth Moving Machinery Co Ltd
Current assignee: Zoomlion Earth Moving Machinery Co Ltd
Priority date: 2021-12-30
Filing date: 2021-12-30
Publication date: 2022-04-29
Anticipated expiration: 2041-12-30
Also published as: CN114411863B

Abstract

The embodiment of the invention provides a positive flow excavator and a control method, a control device and a controller thereof, wherein the control method for the positive flow excavator comprises the following steps: determining whether to turn on a preload function; under the condition that the preloading function is determined to be started, determining whether the positive flow excavator is in a working state; under the condition that the positive flow excavator is not in a working state, controlling a middle position bypass valve to be in a cut-off state so that hydraulic oil output by a main pump can not flow back to a hydraulic oil tank through the middle position bypass valve; and under the condition that the positive flow excavator is in a working state, controlling the middle position bypass valve to be in a conducting state so as to enable hydraulic oil to flow back to the hydraulic oil tank through the middle position bypass valve. The embodiment of the invention can solve the problem of flameout of the positive flow excavator in the plateau area under the condition of not reducing the absorption power of the main pump, namely not reducing the load rate of the engine, and simultaneously can not cause the problems of serious reduction of the dynamic property, slow action speed, low working efficiency and the like compared with the plateau area.

Description

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

Technical Field

The invention relates to the technical field of positive flow excavator control, in particular to a positive flow excavator and a control method, a control device and a controller thereof.

Background

In the normal flow rate excavator, the load factor of the engine is 20% or less in the idling state, and the load factor of the engine instantaneously rises to 70% or more after the operation of the normal flow rate excavator. When the positive flow excavator works in a high-altitude area, under the condition of an altitude of 4000- & ltSUB & gt plus 5000 meters, the air density is only about 60% of that of a plain area, so that the responsiveness of an engine is poor, and the phenomena of power mismatch such as weakness, falling speed, black smoke, vehicle holding and the like frequently occur when the positive flow excavator works in the high-altitude area. Not only influences work efficiency, but also the positive flow excavator works in the plateau area for a long time and seriously reduces the service life of the positive flow excavator. In order to enable a positive flow excavator to normally work in a plateau area, an existing positive flow excavator plateau self-adaptive Control system obtains atmospheric pressure through an ECM (Engine Control Module) or obtains working position information of the positive flow excavator through a TGU (remote Control Unit), the altitude is indirectly calculated through the position information, then whether the operation is plateau operation is judged through the altitude information, and the working condition of the plateau operation is adapted in a mode of reducing the absorbed power of a main pump under the condition of the plateau operation. Therefore, it is urgently needed to provide a technical solution to solve the above technical problems in the prior art.

Disclosure of Invention

The embodiment of the invention aims to provide a positive flow excavator and a control method, a control device and a controller thereof, and solves the technical problems that the conventional plateau self-adaptive control system of the positive flow excavator adopts a mode of reducing the absorbed power of a hydraulic system in a plateau area, and the dynamic property is seriously reduced compared with the plateau area, the action speed is slow and the working efficiency is low while the phenomenon of flameout of a car in the plateau area is solved.

In order to achieve the above object, a first aspect of the present invention provides a control method for a positive flow excavator, the positive flow excavator including a hydraulic system including a neutral bypass valve, a main pump, and a hydraulic oil tank, the control method comprising: determining whether to turn on a preload function; under the condition that the preloading function is determined to be started, determining whether the positive flow excavator is in a working state; under the condition that the positive flow excavator is not in a working state, controlling a middle position bypass valve to be in a cut-off state so that hydraulic oil output by a main pump can not flow back to a hydraulic oil tank through the middle position bypass valve; and under the condition that the positive flow excavator is in a working state, controlling the middle position bypass valve to be in a conducting state so as to enable hydraulic oil to flow back to the hydraulic oil tank through the middle position bypass valve.

In an embodiment of the present invention, determining whether to turn on the preload function includes: determining whether a preload function on command is received; under the condition of receiving a preloading function starting command, acquiring the atmospheric pressure of the environment where the positive flow excavator is located; and determining whether to activate the preload function according to atmospheric pressure; the preloading function starting command is triggered by responding to the selection of an operator to start the preloading function operation.

In an embodiment of the present invention, determining whether to activate the preload function according to the atmospheric pressure includes: determining whether the atmospheric pressure is less than a preset atmospheric pressure threshold value; determining to start a preloading function under the condition that the atmospheric pressure is smaller than a preset atmospheric pressure threshold value; and determining not to start the preloading function under the condition that the atmospheric pressure is not less than the preset atmospheric pressure threshold value.

In an embodiment of the present invention, determining whether the positive flow excavator is in an operating state comprises: acquiring pilot pressure of an operating mechanism corresponding to an executing mechanism of the positive flow excavator; and determining whether the positive flow excavator is in a working state according to the pilot pressure.

In an embodiment of the present invention, determining whether a positive flow excavator is in a working state according to a pilot pressure comprises: determining that the positive flow excavator is not in a working state under the condition that pilot pressures of control mechanisms corresponding to all executing mechanisms of the positive flow excavator are smaller than a preset pressure threshold; and determining that the positive flow excavator is in a working state under the condition that the pilot pressure of the control mechanism corresponding to any one execution mechanism of the positive flow excavator is not less than a preset pressure threshold value.

In an embodiment of the present invention, an actuator includes: a movable arm; a bucket rod; a bucket; a boarding platform; and a traveling mechanism.

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

A third aspect of the present invention provides a control apparatus for a positive flow excavator, the positive flow excavator including a hydraulic system, the hydraulic system including a neutral bypass valve, a main pump, and a hydraulic oil tank, the control apparatus comprising: a preload solenoid valve configured to control the mid-position bypass valve to be in a conducting state or a blocking state; and the controller of the foregoing embodiment.

In an embodiment of the present invention, the control apparatus for a positive flow rate excavator further includes: the pre-loading function selection equipment is configured to respond to the selection of an operator to start the pre-loading function operation and send a pre-loading function starting command; and an atmospheric pressure detection device configured to detect an atmospheric pressure of an environment in which the positive flow shovel is located.

In an embodiment of the present invention, the control apparatus for a positive flow rate excavator further includes: and a pressure detection device configured to detect a pilot pressure of a steering mechanism corresponding to an actuator of the positive flow excavator.

In an embodiment of the present invention, a pressure detection apparatus includes: a boom pressure sensor configured to detect a pilot pressure of an operating mechanism corresponding to a boom of the positive flow excavator; an arm pressure sensor configured to detect a pilot pressure of an operating mechanism corresponding to an arm of the positive flow excavator; a bucket pressure sensor configured to detect a pilot pressure of an operating mechanism corresponding to a bucket of the positive flow excavator; a swing pressure sensor configured to detect a pilot pressure of an operating mechanism corresponding to a loading platform of the positive flow excavator; and a travel pressure sensor configured to detect a pilot pressure of an operation mechanism corresponding to a travel mechanism of the positive flow rate excavator.

A fourth aspect of the present invention provides a positive flow excavator comprising: the hydraulic system comprises a middle position bypass valve, a main pump and a hydraulic oil tank; and the control device for a positive flow rate excavator of the foregoing embodiment.

According to the embodiment of the invention, through the technical scheme, the hydraulic energy of the engine during operation in the plateau area can be fully utilized under the condition of not reducing the absorbed power of the main pump, namely the load rate of the engine, so that the output power of the engine can be more effectively applied to the operation, the problem that the plateau area of the positive flow excavator is subjected to flameout can be solved, and the problems of serious reduction of the dynamic property of the plateau area, low action speed, low working efficiency and the like can be avoided.

Additional features and advantages of embodiments of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the embodiments of the invention without limiting the embodiments of the invention. In the drawings:

FIG. 1 is a flow chart diagram of a control method 100 for a positive flow excavator according to an embodiment of the present disclosure;

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

FIG. 3 is a schematic structural diagram of a positive flow excavator 300 of an embodiment of the present invention; and

FIG. 4 is a schematic diagram of a positive flow excavator to which the present invention exemplary positive flow excavator preload control system is applied.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating embodiments of the invention, are given by way of illustration and explanation only, not limitation.

It should be noted that, if directional indications (such as up, down, left, right, front, and rear … …) are referred to in the embodiments of the present application, the directional indications are only used to explain the relative positional relationship between the components, the movement situation, and the like in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indications are changed accordingly.

In addition, if there is a description of "first", "second", etc. in the embodiments of the present application, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed 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 such feature. In addition, technical solutions between the various embodiments can be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present application.

As shown in fig. 1, in an embodiment of the present invention, there is provided a control method 100 for a positive flow excavator, the positive flow excavator including a hydraulic system including a mid-position bypass valve, a main pump, and a hydraulic tank, the control method 100 for the positive flow excavator including the steps of:

step S110: it is determined whether the preload function is turned on.

Step S120: in the case where it is determined that the preload function is turned on, it is determined whether the positive flow excavator is in an operating state.

Step S130: when the positive flow excavator is not in a working state, the middle position bypass valve is controlled to be in a cut-off state, so that hydraulic oil output by the main pump cannot flow back to the hydraulic oil tank through the middle position bypass valve. And

step S140: and under the condition that the positive flow excavator is in a working state, controlling the middle position bypass valve to be in a conducting state so as to enable the hydraulic oil to flow back to the hydraulic oil tank through the middle position bypass valve.

Specifically, it is determined whether to start the preloading function, that is, step S110 includes, for example:

(a1) it is determined whether a preload function on command is received. The preloading function starting command is triggered by responding to the selection of an operator to start the preloading function operation.

(a2) And acquiring the atmospheric pressure of the environment where the positive flow excavator is located under the condition that a preloading function starting command is received. Specifically, for example, the atmospheric pressure of the environment where the positive flow excavator is located is obtained by an atmospheric pressure detection device such as an atmospheric pressure sensor. And

(a3) whether to activate the preload function is determined based on atmospheric pressure.

Specifically, determining whether to activate the preload function according to the atmospheric pressure, that is, the step (a3), for example, includes:

(a31) it is determined whether the atmospheric pressure is less than a preset atmospheric pressure threshold. The preset barometric pressure threshold may be, for example, 65kpa, or other suitable value less than 65 kpa. The preset atmospheric pressure threshold value is pre-stored locally in advance or set through a display and other man-machine interaction equipment, for example.

(a32) And determining to start the preloading function under the condition that the atmospheric pressure is less than a preset atmospheric pressure threshold value. And

(a33) and under the condition that the atmospheric pressure is not less than the preset atmospheric pressure threshold value, determining not to start the preloading function.

Of course, the embodiment of the present invention is not limited to this, and for example, the preload function may be determined to be turned on when the atmospheric pressure is not greater than the preset atmospheric pressure threshold, and the preload function may not be turned on when the atmospheric pressure is greater than the preset atmospheric pressure threshold.

Specifically, it is determined whether the positive flow excavator is in the working state, that is, step S120 includes, for example:

(b1) and acquiring pilot pressure of an operating mechanism corresponding to an actuating mechanism of the positive flow excavator. Specifically, a pilot pressure of an operating mechanism corresponding to an actuator of a positive flow excavator is acquired by a pressure detection device such as a pressure sensor. The actuating device assigned to an actuator is, for example, an actuating device for actuating the actuator. And

(b2) and determining whether the positive flow excavator is in a working state according to the pilot pressure.

More specifically, it is determined whether the positive flow excavator is in an operating state according to the pilot pressure, that is, the step (b2) includes, for example:

(b21) and under the condition that the pilot pressures of the control mechanisms corresponding to all the actuating mechanisms of the positive flow excavator are smaller than a preset pressure threshold value, determining that the positive flow excavator is not in a working state. The preset pressure threshold may be, for example, 5Bar, or other suitable value. The preset pressure threshold value is pre-stored locally in advance or set through a display and other man-machine interaction equipment, for example. And

(b22) and under the condition that the pilot pressure of the control mechanism corresponding to any one execution mechanism of the positive flow excavator is not less than a preset pressure threshold value, determining that the positive flow excavator is in a working state.

Of course, the embodiment of the present invention is not limited to this, and for example, it may be determined that the positive flow excavator is not in the operating state when the pilot pressures of the control mechanisms corresponding to all the actuators of the positive flow excavator are not greater than the preset pressure threshold, and determined that the positive flow excavator is in the operating state when the pilot pressure of the control mechanism corresponding to any one of the actuators of the positive flow excavator is greater than the preset pressure threshold.

Specifically, the actuator includes, for example: the device comprises a movable arm, a bucket rod, a bucket, a loading platform and a traveling mechanism. In particular, the actuating device is, for example, a handle or a foot pedal, and the actuating device assigned to the actuating device is, for example, a handle or a foot pedal for actuating the actuating device.

In an embodiment of the invention, a controller is provided, for example configured to perform a 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 related description of the foregoing embodiments, and further description is omitted here.

Specifically, the controller may be a control device such as an industrial personal computer, an embedded system, a microprocessor, and a programmable logic device, and specifically may be a VCU (Vehicle control unit) of a positive flow excavator.

As shown in fig. 2, in an embodiment of the present invention, there is provided a control apparatus 200 for a positive flow excavator, the positive flow excavator including a hydraulic system including a neutral bypass valve, a main pump, and a hydraulic tank, the control apparatus 200 for a positive flow excavator including: a controller 210 and a preload solenoid valve 230.

Wherein the controller 210 is, for example, a controller according to any one of the previous embodiments. The detailed functions and details of the controller 210 can be referred to the related descriptions of the foregoing embodiments, and are not repeated herein.

The preload solenoid valve 230 is configured to control the mid bypass valve to be in either a conducting state or a blocking state, for example.

Further, the control device 200 for a positive flow rate excavator, for example, further includes: a pre-load function selection device 250 and a barometric pressure sensing device 270.

The pre-loading function selecting device 250 is configured to send a pre-loading function starting command in response to the selection of the pre-loading function starting operation of an operator. The pre-loaded function selection device 250 may be, for example, a display, and may specifically be, for example, an in-vehicle display of a positive flow excavator.

The atmospheric pressure detection device 270 is configured to detect, for example, the atmospheric pressure of the environment in which the positive flow shovel is located. The atmospheric pressure detection device 270 may be, for example, an atmospheric pressure sensor.

Further, the control apparatus 200 for a positive flow rate excavator further includes, for example, a pressure detection device 290, and the pressure detection device 290 is configured to detect, for example, a pilot pressure of a steering mechanism corresponding to an actuator of the positive flow rate excavator. The pressure detection device 290 may be, for example, a pressure sensor. The actuating device assigned to an actuator is, for example, an actuating device for actuating the actuator. In particular, the actuating device is, for example, a handle or a foot pedal, and the actuating device assigned to the actuating device is, for example, a handle or a foot pedal for actuating the actuating device.

Specifically, the pressure detection device 290 includes, for example: a boom pressure sensor, a stick pressure sensor, a bucket pressure sensor, a swing pressure sensor, and a travel pressure sensor.

Among these, the boom pressure sensor is configured to detect a pilot pressure of a manipulation mechanism corresponding to a boom of a positive flow excavator, for example.

The arm pressure sensor is configured to detect a pilot pressure of a steering mechanism corresponding to an arm of a positive flow excavator, for example.

The bucket pressure sensor is configured to detect a pilot pressure of a steering mechanism corresponding to a bucket of the positive flow excavator, for example.

The swing pressure sensor is configured to detect a pilot pressure of a steering mechanism corresponding to a loading platform of the positive flow excavator, for example.

The travel pressure sensor is configured to detect a pilot pressure of a steering mechanism corresponding to a travel mechanism of a positive flow excavator, for example.

In an embodiment of the present invention, there is provided a positive flow excavator 300 including: a control device 310 and a hydraulic system 330.

Here, the control device 310 is, for example, the control device 200 for a positive flow rate excavator according to any one of the foregoing embodiments. The detailed functions and details of the control device 310 can be referred to the related descriptions of the foregoing embodiments, and are not repeated herein.

The hydraulic system 330 includes, for example, a neutral bypass valve, a main pump, and a hydraulic oil tank.

It should be noted that, for example, by obtaining the location information of the environment where the positive flow excavator is located, determining the altitude information at the location according to the location information, and determining whether to allow the preload function to be started according to whether the altitude is greater than a set altitude threshold, for example, 3500 m or an appropriate altitude threshold greater than 3500 m. Accordingly, the position information can be acquired by a position detection device such as a GPS, for example.

The operation of the control method 100 for a positive flow excavator according to an embodiment of the present invention is described in detail below with reference to a specific example, which includes the following specific contents:

in order to solve the problems that a positive flow excavator is powerless and emits black smoke during plateau operation, the invention provides a positive flow excavator preloading control system.

As shown in fig. 4, which is a schematic structural diagram of a positive flow excavator to which the preload control system of the positive flow excavator provided by the example of the present invention is applied, component names and corresponding reference numbers in fig. 4 are as follows:

the system comprises an on-board display 101, a VCU102, an ECM 103, a pressure sensor group 104, a master valve group 201, a master valve group 202, an overflow valve 203, an overflow valve 204, a master pump 205, a master pump 206, an engine 207, a preload neutral bypass valve 208, a preload neutral bypass valve 209, a barometric pressure sensor 211, a preload solenoid valve 304, a preload solenoid valve 305, a master pump power solenoid valve 301, a pump power solenoid valve 302, and a hydraulic reservoir 303. The pressure sensor group 104 includes a boom pressure sensor 104-1, a boom pressure sensor 104-2, an arm pressure sensor 104-3, an arm pressure sensor 104-4, a bucket pressure sensor 104-5, a bucket pressure sensor 104-6, a swing pressure sensor 104-7, a travel pressure sensor 104-8, and a travel pressure sensor 104-9.

The exemplary positive flow excavator preload control system of the present invention generally comprises: the hydraulic control system comprises a preloading neutral bypass valve 208, a preloading electromagnetic valve 305, a preloading neutral bypass valve 209, a preloading electromagnetic valve 304, an atmospheric pressure sensor 211, a main pump power electromagnetic valve 301, a main pump power electromagnetic valve 302, a VCU102 and a vehicle-mounted display 101, wherein the preloading neutral bypass valve 208 is installed between a main control valve group 201 and a hydraulic oil tank 303 and used for controlling neutral oil return of a hydraulic system, the preloading electromagnetic valve 305 is used for controlling backflow of the preloading neutral bypass valve 208, the preloading electromagnetic valve 304 is used for monitoring atmospheric pressure, and the main pump power electromagnetic valve 301, the main pump power electromagnetic valve 302, the VCU102 and the vehicle-mounted display 101 are used for human-computer interaction.

First, judging whether to start the preloading function

The VCU102 monitors an atmospheric pressure value of a current normal flow excavator working environment through the atmospheric pressure sensor 211, the VCU102 acquires data of the atmospheric pressure sensor 211 through the CAN bus, the VCU102 determines whether the atmospheric pressure value of the current normal flow excavator working environment is smaller than an atmospheric pressure threshold set by the system, after the atmospheric pressure value is smaller than the atmospheric pressure threshold set by the system, the system is allowed to start a preloading function, according to a corresponding relationship between the atmospheric pressure and an altitude, the atmospheric pressure in a plain area is about 101kpa, the altitude is 1000 meters per liter, the atmospheric pressure is about 10kpa, and the engine power is obviously reduced in the plateau area with the altitude of 3500 meters or more under a normal condition.

When a user drives the positive flow excavator to work in a plateau area, whether the preloading function is started is selected through a menu setting interface of the vehicle-mounted display 101, and after receiving the operation of the user, the vehicle-mounted display 101 sends an operation instruction to the VCU102 through the CAN bus. The VCU102 determines whether to start the pre-loading function according to whether the data of the barometric pressure sensor 211 is smaller than the barometric pressure threshold set by the system and whether the user selects to start the pre-loading function through the in-vehicle display 101. In the case where the atmospheric pressure value of the atmospheric pressure sensor 211 is smaller than the atmospheric pressure threshold set by the system and the user selects to turn on the preload function through the in-vehicle display 101, the system turns on the preload function.

Second, judging the working state of the positive flow excavator

As shown in fig. 4, the VCU102 may obtain detection data of all pressure sensors of the pressure sensor group 104, including the boom pressure sensor 104-1, the boom pressure sensor 104-2, the arm pressure sensor 104-3, the arm pressure sensor 104-4, the bucket pressure sensor 104-5, the bucket pressure sensor 104-6, the swing pressure sensor 104-7, the walking pressure sensor 104-8, and the walking pressure sensor 104-9, and if pressure values detected by all pressure sensors of the pressure sensor group 104 are less than 5Bar, it is determined that the whole positive flow excavator does not work, that is, is not in a working state, and if a pressure value detected by any pressure sensor of the pressure sensor group 104 is not less than 5Bar, it is determined that the whole positive flow excavator works, that is, in a working state.

Thirdly, when the preloading function is not started

When the preload function is not on, the VCU102 does not control the

preload solenoids

304, 305, and the

preload solenoids

304, 305 are in an unpowered state, at which time the spools of the

neutral bypass valves

208, 209 are both on the right side, and the

neutral bypass valves

208, 209 are in a conducting state.

When the VCU102 determines that the positive flow excavator does not work, that is, is not in a working state, by obtaining detection data of all pressure sensors of the pressure sensor group 104, the VCU102 outputs current to the main pump power

electromagnetic valves

301 and 302 to enable the

main pumps

205 and 206 to work in a minimum displacement state, and at this time, hydraulic oil output by the

main pumps

205 and 206 flows through the main control valve group 201 and the main control valve group 202 and then directly flows back to the oil tank 303 through the preloaded

neutral bypass valves

208 and 209. At this time, the displacements of the

main pumps

205, 206 are at a minimum, and the outlet pressures of the

main pumps

205, 206 are also at a minimum. While the load factor of the engine 207 is also at a minimum. Normally, the engine load rate is about 20% when the positive flow excavator complete machine is not in operation.

When the VCU102 judges that the overall state of the positive flow excavator is switched from the non-operation state to the working state by obtaining the detection data of all the pressure sensors of the pressure sensor group 104, the VCU102 outputs current to the main pump power

electromagnetic valves

301 and 302 to enable the

main pumps

205 and 206 to work in a set displacement state, at this time, hydraulic oil output by the

main pumps

205 and 206 mainly flows to corresponding execution devices after passing through the main control valve group 201 and the main control valve group 202, and a small part of middle-position leakage oil flows back to the oil tank 303 through the middle-

position bypass valves

208 and 209.

Fourth, when the preloading function is started

1. When the positive flow excavator does not work

When the VCU102 determines that the current positive flow excavator does not operate by acquiring the detection data of all the pressure sensors of the pressure sensor group 104, it outputs a 24V voltage signal to the preload solenoid valve 305, and at this time, the electric spool of the middle bypass valve 208 is located on the left side, and the middle bypass valve 208 is in the off state. The VCU102 outputs current to the main pump power solenoid valve 301 to enable the main pump 205 to operate in a minimum displacement state, at this time, since the middle position bypass valve 208 is in a cut-off state, the main pump 205 outputs hydraulic oil to return to the hydraulic oil tank 303 through the overflow valve 203, the overflow pressure of the overflow valve 203 is normally set to 34Mpa, and the overflow pressure of the overflow valve 203 may be set to other suitable values within a range from 31Mpa to 37 Mpa. The states of the components at this time are as follows: the displacement of the main pump 205 is at a minimum, and at the same time, because the neutral bypass valve 208 is at a cut-off state, so that the neutral oil return through the neutral bypass valve 208 is cut off, the main pump 205 is at a relief state, the outlet pressure of the main pump 205 is also at 34Mpa, and the absorbed power of the main pump 205 is higher due to the increase of the outlet pressure of the main pump 205, and the load factor of the engine 207 is increased by about 10% compared with the prior art.

Similarly, when the VCU102 determines that the current positive flow excavator does not operate by acquiring the detection data of all the pressure sensors of the pressure sensor group 104, it outputs a 24V voltage signal to the preload solenoid valve 304, and at this time, the electric spool of the middle bypass valve 209 is located on the left side, and the middle bypass valve 209 is in the off state. The VCU102 outputs current to the main pump power solenoid valve 302 to enable the main pump 206 to operate in a minimum displacement state, at this time, since the neutral bypass valve 209 is in a cut-off state, the main pump 206 outputs hydraulic oil to return to the hydraulic oil tank 303 through the overflow valve 204, the overflow pressure of the overflow valve 204 is normally set to 34Mpa, and the overflow pressure of the overflow valve 204 may be set to other suitable values within a range from 31Mpa to 37 Mpa. The states of the components at this time are as follows: the displacement of the main pump 206 is at a minimum state, and at the same time, because the neutral bypass valve 209 is in a cut-off state, the neutral return oil passing through the neutral bypass valve 209 is cut off, the main pump 206 is in a relief state, the outlet pressure of the main pump 206 is also 34Mpa, the power absorption of the main pump 206 is higher due to the increase of the outlet pressure of the main pump 206, and the load factor of the engine 207 is further increased by about 10% compared with the prior art. The VCU102 can increase the engine load rate by about 20% compared to the prior art as a whole by controlling the preload solenoid valve 304 and the preload solenoid valve 305 so that both the main pump 205 and the main pump 206 are in the flooding state, and the engine load rate of the conventional positive flow excavator is about 20% when in the non-operating state, so that the engine load rate can be increased from about 20% to about 40% when in the non-operating state.

In particular implementations, engine responsiveness and actual measured engine load rate may be combined, selected via the on-board display 101, with one of the

primary pumps

205 or 206 selected for preloading or both

primary pumps

205 and 206 preloaded at the same time.

In the case where the VCU102 floods the main pump 205 by controlling only the preload solenoid valve 305, or floods the main pump 206 by controlling only the preload solenoid valve 304, i.e., selects one of the

main pumps

205 or 206 for preloading, the engine load rate may be increased by about 10% over the prior art as a whole, i.e., the engine load rate may be increased from about 20% to about 30% of the prior art.

2. When the positive flow excavator is in a working state

When the VCU102 determines that the current positive flow excavator is switched from the non-operation state to the operation state by acquiring the detection data of all the pressure sensors of the pressure sensor group 104, the VCU102 does not control the

preload solenoid valves

304 and 305, the

preload solenoid valves

304 and 305 are in the non-energized state, and at this time, the spool of the middle bypass valve 208209 is located on the right side. The VCU102 outputs current to the main pump

power solenoid valves

301 and 302, so that the

main pumps

205 and 206 operate in a set displacement state, and at this time, the

main pumps

205 and 206 output hydraulic oil which mainly flows to corresponding actuators after passing through the main valve group 201 and the main valve group 202. And a small part of the middle leakage oil flows back to the oil tank 303 through the middle bypass valve 208 and the middle bypass valve 209.

In summary, according to the embodiments of the present invention, based on the existing components of the positive flow system of the positive flow excavator, under the condition that the absorbed power of the main pump, that is, the load factor of the engine, is not reduced, the hydraulic energy of the engine during operation in the plateau area is fully utilized, the output power of the engine is more effectively applied to the operation, the action speed and the operation efficiency of the machine in the plateau area can be effectively increased, the problem of flameout of the vehicle in the plateau area of the positive flow excavator can be solved, and the problems of severe reduction of the power performance in the plateau area, slow action speed, low working efficiency, and the like, can not be caused. The engine load rate is increased to about 40% when the whole engine does not work, so that the engine load rate is increased from 20% to 70% instantly at the moment of the current instant action to 40% to 70%, and the problem that the engine responsiveness is poor is effectively solved.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention 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, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams 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 apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

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

The memory may include forms of volatile memory in a computer readable medium, Random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). The memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, 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), 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 Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, a computer readable medium does not include a transitory computer readable medium such as a modulated data signal and a carrier wave.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.

The above are merely examples of the present invention, and are not intended to limit the present invention. Various modifications and alterations to this invention will become apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A control method for a positive flow excavator, the positive flow excavator comprising a hydraulic system including a mid-position bypass valve, a main pump and a hydraulic tank, the control method comprising:

determining whether to turn on a preload function;

determining whether the positive flow excavator is in a working state under the condition that the preloading function is determined to be started;

under the condition that the positive flow excavator is not in a working state, controlling the middle position bypass valve to be in a cut-off state, so that hydraulic oil output by the main pump cannot flow back to the hydraulic oil tank through the middle position bypass valve; and

and under the condition that the positive flow excavator is in a working state, controlling the middle position bypass valve to be in a conducting state, so that the hydraulic oil can flow back to the hydraulic oil tank through the middle position bypass valve.

2. The control method of claim 1, wherein the determining whether to activate a preload function comprises:

determining whether a preload function on command is received;

under the condition of receiving a preloading function starting command, acquiring the atmospheric pressure of the environment where the positive flow excavator is located; and

determining whether to start the preloading function according to the atmospheric pressure;

wherein the pre-loading function starting command is triggered by responding to the selection of an operator to start the pre-loading function operation.

3. The control method of claim 2, wherein the determining whether to activate the preload function based on the barometric pressure comprises:

determining whether the atmospheric pressure is less than a preset atmospheric pressure threshold;

determining to start the preloading function when the atmospheric pressure is smaller than the preset atmospheric pressure threshold; and

determining not to turn on the preload function if the barometric pressure is not less than the preset barometric pressure threshold.

4. The control method of claim 1, wherein said determining whether the positive flow excavator is in an operational state comprises:

acquiring pilot pressure of an operating mechanism corresponding to an executing mechanism of the positive flow excavator; and

and determining whether the positive flow excavator is in a working state or not according to the pilot pressure.

5. The control method of claim 4, wherein said determining whether the positive flow excavator is in an operational state based on the pilot pressure comprises:

determining that the positive flow excavator is not in a working state under the condition that pilot pressures of control mechanisms corresponding to all execution mechanisms of the positive flow excavator are smaller than a preset pressure threshold; and

and under the condition that the pilot pressure of the control mechanism corresponding to any one execution mechanism of the positive flow excavator is not less than the preset pressure threshold value, determining that the positive flow excavator is in a working state.

6. The control method according to claim 4, wherein the actuator includes:

a movable arm;

a bucket rod;

a bucket;

a boarding platform; and

a traveling mechanism.

7. A controller, characterized by being configured to execute the control method for a positive flow excavator according to any one of claims 1 to 6.

8. A control apparatus for a positive flow excavator, the positive flow excavator comprising a hydraulic system including a neutral bypass valve, a main pump and a hydraulic oil tank, the control apparatus comprising:

a preload solenoid valve configured to control the mid-position bypass valve to be in a conducting state or a blocking state; and

the controller of claim 7.

9. The control device according to claim 8, characterized by further comprising:

the pre-loading function selection equipment is configured to respond to the selection of an operator to start the pre-loading function operation and send a pre-loading function starting command; and

an atmospheric pressure detection device configured to detect an atmospheric pressure of an environment in which the positive flow shovel is located.

10. The control device according to claim 8, characterized by further comprising:

and a pressure detection device configured to detect a pilot pressure of a steering mechanism corresponding to an actuator of the positive flow excavator.

11. The control apparatus according to claim 10, wherein the pressure detecting device includes:

a boom pressure sensor configured to detect a pilot pressure of an operation mechanism corresponding to a boom of the positive flow excavator;

an arm pressure sensor configured to detect a pilot pressure of an operating mechanism corresponding to an arm of the positive flow excavator;

a bucket pressure sensor configured to detect a pilot pressure of an operating mechanism corresponding to a bucket of the positive flow excavator;

a swing pressure sensor configured to detect a pilot pressure of an operating mechanism corresponding to a loading platform of the positive flow excavator; and

and a travel pressure sensor configured to detect a pilot pressure of an operation mechanism corresponding to a travel mechanism of the positive flow rate excavator.

12. A positive flow excavator, comprising:

the hydraulic system comprises a middle position bypass valve, a main pump and a hydraulic oil tank; and

the control device for a positive flow excavator according to any one of claims 8 to 11.