CN115784052A - Crane amplitude falling control method and device and crane - Google Patents

Abstract

The application relates to the technical field of engineering machinery, in particular to a crane amplitude falling control method, a device and a crane, wherein the method comprises the steps of determining a target amplitude falling speed at which a driver wants to operate the crane through the opening degree of a handle; and then determining and controlling the flow area of the balance valve to be kept at the target flow area which can enable the crane to fall at the target falling speed at the uniform speed according to the working condition data and the target falling speed of the crane, thereby automatically controlling the uniform falling of the crane and greatly improving the stability and the safety of the falling of the crane.

Description

Crane amplitude falling control method and device and crane

Technical Field

The application relates to the technical field of engineering machinery, in particular to a crane amplitude falling control method and device and a crane.

Background

The dropping amplitude performance of the crane is one of important indexes for measuring the controllability of the crane, and when the automobile crane of the electric control flow system drops amplitude, the vertical speed of the arm head lifting hook is faster and faster under the condition that the opening of the handle is not changed, so that the crane has great potential safety hazard when dropping amplitude.

In the prior art, in order to ensure that the amplitude falling speed is controlled, generally, in the process that the amplitude falling angle of the crane is gradually reduced, the opening degree of an amplitude-changing balance valve of the crane is adjusted in real time by manually controlling the opening degree of an operating handle, so that the amplitude falling speed is controlled. Or during the amplitude falling operation of the crane, acquiring a pressure value of a rodless cavity in the rodless cavity of the amplitude-varying oil cylinder; and controlling the electric proportional overflow valve to adjust the pressure of the rod cavity of the amplitude-variable oil cylinder based on the difference value between the pressure value of the rodless cavity and the preset standard pressure value, thereby controlling the amplitude falling speed.

However, the opening degree of the operating handle is difficult to control accurately, the requirements on the driving experience of a driver are high, the falling amplitude speed of the crane is difficult to control accurately by the driver, and the operation difficulty of the driver is high; and the amplitude falling process is difficult to be accurately embodied only through the pressure data of the rodless cavity, and meanwhile, the amplitude falling process is difficult to be accurately controlled based on the pressure data of the rodless cavity, so that the stability and the safety of the amplitude falling of the crane cannot be ensured.

Disclosure of Invention

In view of the above, the present invention is directed to a method and an apparatus for controlling a boom of a crane, and a crane.

In a first aspect, the present invention provides a method for controlling a boom falling of a crane, including:

acquiring handle opening and working condition data of the crane;

determining a target amplitude falling speed based on the handle opening degree;

determining a target flow area of a balance valve of the crane based on the target amplitude falling speed and the working condition data, wherein the target flow area is the flow area of the balance valve which can enable the crane to fall amplitude at the target amplitude falling speed and the target amplitude falling speed;

and controlling the flow area of the balance valve to be the target flow area so as to enable the crane to fall at the target falling speed and speed.

Optionally, the working condition data includes a large boom length, a large boom luffing angle, a crane structural parameter, and a pressure of a rodless cavity of a luffing cylinder of the crane.

Optionally, the determining a target flow area of a balance valve of the crane based on the target landing amplitude speed and the operating condition data includes:

determining a target cylinder speed of a luffing cylinder of the crane based on the target luffing speed, the length of the large boom, the luffing angle of the large boom and the structural parameters of the crane; the target cylinder speed is the speed of the amplitude-variable cylinder which can enable the crane to drop the amplitude at the target amplitude-dropping speed uniformly;

determining the target rodless cavity flow of the luffing oil cylinder based on the target oil cylinder speed; the flow of the target rodless cavity is the rodless cavity flow of the luffing oil cylinder which can enable the luffing oil cylinder to keep the speed of the target oil cylinder;

determining the target flow area based on the target rodless cavity flow and the pressure of the rodless cavity of the variable-amplitude oil cylinder; the target flow area is the flow area of the balance valve which can enable the amplitude variation oil cylinder to keep the flow of the target rodless cavity.

Optionally, the determining a target cylinder speed of a luffing cylinder of the crane based on the target luffing speed, the length of the boom, the luffing angle of the boom, and the crane structural parameter includes:

calculating to obtain the target oil cylinder speed according to a preset formula based on the target amplitude falling speed, the length of the large boom, the amplitude changing angle of the large boom and the structural parameters of the crane;

the preset formula comprises:

wherein, V ₂ For the target oil cylinder speed, A is the distance between the arm tail hinge point of the crane and the upper hinge point of the luffing oil cylinder, B is the distance between the arm tail hinge point of the crane and the lower hinge point of the luffing oil cylinder, and V ₁ And theta is the amplitude variation angle of the large arm of the crane, beta is the included angle between the horizontal line and the straight line where the tail hinge point of the arm of the crane and the lower hinge point of the amplitude variation oil cylinder are located, and L is the length of the large arm.

Optionally, the crane structural parameters comprise a first distance and a second distance;

the first distance is the distance between the arm tail hinge point of the crane and the upper hinge point of the luffing oil cylinder, and the second distance is the distance between the arm tail hinge point of the crane and the lower hinge point of the luffing oil cylinder.

Optionally, the controlling the flow area of the balancing valve to be the target flow area includes:

and controlling the flow area of the balance valve to be kept at the target flow area through a proportional valve on the crane.

Optionally, said controlling the flow area of the balancing valve to be maintained at the target flow area by a proportional valve on the crane, comprises:

determining a target current value of the proportional valve based on the target flow area; wherein the target current value is a current value of the proportional valve that can maintain a flow area of the balance valve at the target flow area;

and controlling the current of the proportional valve to be the target current value so as to enable the flow area of the balance valve to be the target flow area.

In a second aspect, an embodiment of the present application further provides a crane amplitude-falling control device, which includes an acquisition module, a calculation control module, and a balance valve;

the acquisition module is used for acquiring the handle opening and working condition data of the crane;

the calculation control module is used for determining a target amplitude falling speed based on the handle opening degree; determining a target flow area of a balance valve of the crane based on the target amplitude falling speed and the working condition data, wherein the target flow area is the flow area of the balance valve which can enable the crane to fall amplitude at the target amplitude falling speed at a uniform speed;

and the calculation control module is also used for controlling the flow area of the balance valve to be the target flow area so as to enable the crane to fall at the target falling speed and the uniform speed.

Optionally, a proportional valve;

the proportional valve is respectively connected with the calculation control module and the balance valve;

and the calculation control module controls the flow area of the balance valve to be the target flow area by controlling the current of the proportional valve.

In a third aspect, embodiments of the present application further provide a crane, including a crane amplitude control apparatus as described above.

The application provides a crane amplitude falling control method device and a crane, wherein the control method comprises the steps of firstly determining a target amplitude falling speed which a driver wants to enable the crane to operate through the opening degree of a handle; and then determining and controlling the flow area of the balance valve to be kept at the target flow area which can enable the crane to fall at the target falling speed at the uniform speed according to the working condition data and the target falling speed of the crane, thereby automatically controlling the uniform falling of the crane and greatly improving the stability and the safety of the falling of the crane.

Drawings

The above and other objects, features and advantages of the present application will become more apparent by describing in more detail embodiments of the present application with reference to the attached drawings. The accompanying drawings are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. In the drawings, like reference numbers generally represent like parts or steps.

Fig. 1 is a schematic flow diagram of a crane amplitude falling control method provided in an embodiment of the present invention.

Fig. 2 is a schematic diagram illustrating a principle of determining a target flow area in a crane amplitude-falling control method provided by an embodiment of the invention.

Fig. 3 is a schematic flow chart of a boom in the crane boom lowering control method provided in the embodiment of the present invention.

Fig. 4 is a schematic flow diagram illustrating the flow area of a variable amplitude balance valve in the crane amplitude falling control method provided by the embodiment of the invention.

Fig. 5 is a schematic flow chart for controlling the flow area of the amplitude balance valve in the crane amplitude falling control method provided by the embodiment of the invention.

Fig. 6 is a schematic structural diagram of a crane amplitude-falling control device according to an embodiment of the present invention.

Fig. 7 is a schematic structural diagram of a crane amplitude control device according to another embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.

Application overview:

the crane luffing is an operation of changing the angle of a crane boom according to actual requirements so as to perform lifting operation, wherein the falling process of the crane boom is changed into luffing. The oil cylinder connected with the crane boom and used for providing power for the crane boom to change amplitude is generally called a variable amplitude oil cylinder, and other components related to the variable amplitude, such as a balance valve, a proportional valve and the like, are changed into a variable amplitude balance valve and a variable amplitude proportional valve.

The amplitude falling performance of the crane is one of important indexes for measuring the operability of the crane, the amplitude falling performance of the crane comprises an automobile crane with an electric control flow system, the amplitude falling process is generally controlled by an operating handle, when amplitude falling action is executed, when a driver controls the handle to be a certain fixed opening degree, the vertical speed of an arm head lifting hook is faster and faster, and the amplitude falling process of the crane has great potential safety hazards due to the speed which is difficult to control and the higher amplitude falling speed.

Therefore, the driver is required to control the operating handle in real time, so that the problem that the falling amplitude speed of the crane is large or uncontrollable to cause danger is avoided, in practical application, the handle operation difficulty is high, the driver only relies on the driving experience, the falling amplitude speed is difficult to control through the operating handle, the falling amplitude stability and safety of the crane are difficult to guarantee, and the falling amplitude process is directly controlled by detecting the pressure of the rodless cavity, the falling amplitude speed of the crane cannot be accurately controlled, and the falling amplitude stability and safety of the crane cannot be guaranteed.

The method comprises the following steps:

fig. 1 is a schematic flow diagram of a crane boom lowering control method provided in an embodiment of the present invention, and as shown in fig. 1, the crane boom lowering control method provided in the embodiment of the present invention includes:

s101, acquiring handle opening and working condition data of the crane.

Specifically, the handle opening degree is the opening degree of a crane control handle and various operation levers, and in practical application, the handle opening degree is adjusted by a driver according to the operation condition of the crane and can be detected by a position sensor arranged near the handle or acquired by detecting a control signal of a related controller and the like. The working condition data comprises the length of a large arm of the crane (the length of a crane arm), the amplitude variation angle of the large arm (the angle of a crane arm in the amplitude falling process), the structural parameters of the crane (including the distance between each hinge point and the like), the pressure of a rodless cavity of an amplitude variation oil cylinder and the like.

And S102, determining a target amplitude falling speed based on the opening degree of the handle.

Specifically, the handle opening is changed by a driver according to the crane operation condition, and the driving intention of the driver can be accurately known by identifying and detecting the handle opening, so that the target dropping speed, which is the dropping speed at which the driver wants to control the crane, is judged.

S103, determining the target through flow area of the balance valve of the crane based on the target amplitude falling speed and the working condition data.

And S104, controlling the flow area of the balance valve to be a target flow area so that the crane can drop the amplitude at the target amplitude dropping speed at a uniform speed.

Wherein the target flow area is the flow area of a balance valve which can make the crane fall at the target falling speed and the uniform speed.

Specifically, the flow area of the amplitude balance valve (namely, the balance valve for providing power for the amplitude falling of the crane) can control the amplitude falling speed of the crane. According to the determined target amplitude falling speed, the flow area of the amplitude-changing balance valve required for maintaining the target amplitude falling speed, namely the target flow area of the balance valve, can be calculated through the working condition data of the crane and various formulas. After the target flow area is obtained through calculation, the flow area of the balance valve is controlled to be changed into and maintained in a target flow area state, so that the crane can maintain uniform amplitude falling in a target amplitude falling speed state.

According to the crane amplitude falling control method, firstly, the target amplitude falling speed at which a driver wants to enable the crane to operate is determined through the opening degree of a handle; and then determining and controlling the flow area of the balance valve to be kept at the target flow area which enables the crane to fall at the target falling speed at the uniform speed according to the working condition data and the target falling speed of the crane, so that the uniform falling of the crane is automatically controlled, and the stability and the safety of the falling of the crane are greatly improved.

After the target flow area of the balance valve is determined, the flow area of the balance valve may be controlled to the target flow area through various signals and devices, for example, the controller may directly send signals such as current and voltage to control the flow area of the balance valve, or the controller may control other devices connected to the balance valve, such as a proportional valve, to indirectly control the flow area of the balance valve to the target flow area.

Fig. 2 is a schematic diagram illustrating a principle of determining a target flow area in a crane boom lowering control method provided by an embodiment of the present invention, fig. 3 is a schematic diagram illustrating a flow of a boom in the crane boom lowering control method provided by the embodiment of the present invention, and fig. 4 is a schematic diagram illustrating a flow in a crane boom lowering control method provided by another embodiment of the present invention, as shown in fig. 2, fig. 3, and fig. 4, in the present application, a flow of determining the target flow area includes:

s201, determining the target oil cylinder speed of the variable amplitude oil cylinder of the crane based on the target amplitude falling speed, the length of the large arm, the variable amplitude angle of the large arm and the structural parameters of the crane.

The target cylinder speed is the speed of the amplitude-variable cylinder which can enable the crane to drop the amplitude at the target amplitude-falling speed.

In particular, the boom length is known and can be detected by a position sensor provided on the boom, which can be indicated by L; the crane structural parameters comprise crane three-hinge-point parameters, the three hinge points of the crane are respectively an arm tail hinge point, an upper hinge point of a luffing cylinder and a lower hinge point of the luffing cylinder, wherein the three-hinge-point parameters comprise the distance between the arm tail hinge point and the upper hinge point of the luffing cylinder, which is represented by A and can be 6.0456m in some cranes, and the distance between the arm tail hinge point and the lower hinge point of the luffing cylinder, which is represented by B and can be 2.6m in some cranes. It should be noted that the crane structural parameters, i.e., a and B, are fixed parameters, and the above example is only for representing the value range of the parameters, and is not a fixed parameter on each crane; the amplitude variation angle is continuously changed in the amplitude variation process of the crane, namely the amplitude falling process, and can be detected by a plurality of angle sensors arranged on the large arm, wherein the angle can comprise a horizontal included angle theta between a tail hinge point of the arm and a connecting line of an upper hinge point of the amplitude variation oil cylinder, and a horizontal included angle beta between the tail hinge point of the arm and a connecting line of a lower hinge point of the amplitude variation oil cylinder.

And after the working condition data and the target amplitude falling speed are obtained, calculating and determining the target oil cylinder speed corresponding to the target amplitude falling speed according to the corresponding relation between the crane amplitude falling speed and the amplitude changing oil cylinder speed.

It should be noted that the amplitude falling speed of the crane, i.e. the vertical falling speed of the boom head hook, is along the vertical direction, and the speed of the luffing cylinder of the crane is not necessarily the same as the amplitude falling speed, and the power output by the luffing cylinder, along with the change of the luffing angle (luffing angle), the force acting on the boom head hook also changes in real time, and according to the kinematic and mechanical formulas, the relationship between the cylinder output power, i.e. the speed of the luffing cylinder and the amplitude falling speed of the crane, during the real-time change of the luffing angle, can be calculated according to the speed component relationship of the speed at the luffing angle, so that according to the target amplitude falling speed determined based on the handle opening, the target cylinder speed that can ensure the crane to maintain the target amplitude falling speed and uniform amplitude falling is determined.

In some embodiments, the specific calculation formula may include:

wherein, V ₂ For the target oil cylinder speed, A is the distance between the arm tail hinge point of the crane and the upper hinge point of the variable amplitude oil cylinder, B is the distance between the arm tail hinge point of the crane and the lower hinge point of the variable amplitude oil cylinder, and V is the distance between the arm tail hinge point of the crane and the lower hinge point of the variable amplitude oil cylinder ₁ And theta is the amplitude variation angle of the large arm of the crane, beta is the included angle between the straight line where the tail hinge point of the arm of the crane and the lower hinge point of the amplitude variation oil cylinder are located and the horizontal line, and L is the length of the large arm.

S202, determining the target rodless cavity flow of the luffing oil cylinder based on the target oil cylinder speed.

The target rodless cavity flow is the rodless cavity flow of the variable amplitude oil cylinder which can enable the variable amplitude oil cylinder to keep the target oil cylinder speed.

Specifically, the speed of the amplitude-variable oil cylinder depends on the rodless cavity flow of the amplitude-variable oil cylinder, namely the rodless cavity flow of the amplitude-variable oil cylinder determines the speed of the amplitude-variable oil cylinder, so that after the target oil cylinder speed is determined in the steps, the target rodless cavity flow capable of enabling the amplitude-variable oil cylinder to maintain the target oil cylinder speed is obtained through calculation according to the motion speed principle of the amplitude-variable oil cylinder.

In some embodiments, the specific formula for calculating the target rodless cavity flow rate according to the target cylinder speed may be:

Q＝V ₂ *S/μ _V ；

wherein Q is the target rodless cavity flow, V ₂ Is the target oil cylinder speed, S is the rodless cavity area of the variable amplitude oil cylinder, mu _V For volumetric efficiency of the luffing cylinder, in some embodiments, μ _V May be taken to be 0.99.

S203, determining a target through flow area based on the target rodless cavity flow and the pressure of the rodless cavity of the variable amplitude oil cylinder.

The target flow area is the flow area of the amplitude-variable oil cylinder which can enable the amplitude-variable oil cylinder to keep the target rodless cavity flow.

Specifically, after the flow of the target rodless cavity of the luffing cylinder is determined, the target flow area of the luffing balance valve can be calculated only by determining the pressure of the rodless cavity, and the pressure of the rodless cavity can be obtained through a preset pressure detector or a control signal in a control circuit. Under the condition that the pressure of the rodless cavity is known, the target flow area for maintaining the flow of the luffing cylinder in the target rodless cavity can be calculated through a relational formula among the pressure of the luffing cylinder, the flow area of the balance valve, the flow and the like.

In some embodiments, based on the target rodless chamber flow rate of the luffing cylinder and the acquired known rodless chamber flow rate, the formula for calculating the target flow area of the balancing valve can be:

and W is the target flow area, alpha is a preset flow coefficient, delta P is the rodless cavity pressure of the amplitude variation oil cylinder, and rho is the hydraulic oil density. In some embodiments, a may be 0.7.

It should be noted that, since the crane luffing is a dynamic process, after the data for calculating the target flow area are obtained, and the target flow area is determined based on the data calculation, the data also change along with the luffing process. Therefore, in the present application, the acquisition of the data and the calculation of the target flow area may not be completed at once, but may be periodically performed in real time. That is, in the whole cropping process, the data may be acquired several times in sequence, the target flow area corresponding to the time is calculated for each acquired data, and then the flow area of the balance valve is controlled, after a preset time interval, new data is acquired again, the target flow area is determined again, and the flow area of the balance valve is controlled based on the newly determined target flow area until the cropping process is finished.

It should be noted that the time interval of acquiring data every two times can be adjusted according to actual requirements, wherein the smaller the time interval is, the higher the frequency of controlling the flow area of the balance valve is, and the more accurate the adjustment of the amplitude falling process is. Of course, in some scenarios where the accuracy requirement is not high, the time interval may be increased appropriately for reasons of power consumption, etc.

According to the crane amplitude variation control method, based on various data detected by a crane in an amplitude falling process, including fixed or real-time changing handle opening, large arm length, amplitude variation angle and crane three-hinge-point structural parameters, the target cylinder speed of an amplitude variation cylinder, corresponding to the handle opening and capable of ensuring that the crane can maintain a target amplitude falling speed state, is calculated according to the corresponding relation between the amplitude falling speed and the speed component of the cylinder speed on the crane; then, calculating according to the relation between the target oil cylinder speed and the flow of the variable amplitude oil cylinder, wherein the rodless cavity flow of the variable amplitude oil cylinder, namely the target rodless cavity flow, of the target oil cylinder speed can be maintained; and finally calculating to obtain the target through-flow area of the balance valve of the amplitude-variable oil cylinder in the target oil cylinder flow state in the amplitude-falling process according to the target rodless cavity flow and the measured rodless cavity pressure flow data, so that the uniform amplitude falling of the crane at the target amplitude-falling speed can be realized by controlling the through-flow area of the amplitude-variable balance valve to be the target through-flow area, and the stability and the safety of the crane amplitude falling are ensured.

In the process, the target amplitude falling speed is determined based on the opening degree of the handle, and in the process of changing the amplitude changing angle and the like, the force on the cargo boom is changed in real time by changing the flow area of the amplitude changing balance valve in real time, so that the uniform amplitude falling of the crane is realized. It can be understood that when the opening of the handle of the crane is changed, namely the target amplitude falling speed is changed, the corresponding subsequent flow is naturally changed, namely a new target flow area of the amplitude variation balance valve is determined and adjusted according to the new target amplitude falling speed.

Fig. 5 is a schematic flow diagram illustrating a process for controlling a flow area of a luffing balance valve in a crane luffing control method according to an embodiment of the present invention, where as shown in fig. 5, the control method may include:

s501, determining a target current value of a proportional valve of the crane based on the target flow area.

Wherein the target current value is a current value of the proportional valve that can maintain a flow area of the balance valve at a target flow area.

Specifically, the calculated target flow area of the variable amplitude balance valve is converted into a control current of the variable amplitude proportional valve, namely a target current value according to a conversion formula determined as required, and the current value can enable the flow area of the variable amplitude balance valve to be maintained at the target flow area. The method includes that the current of the control device (proportional valve) is calculated according to the flow area of the controlled device (balance valve), and therefore the method is not specifically described herein.

S502, controlling the current of the proportional valve to be a target current value so that the flow area of the balance valve is a target flow area.

Specifically, after the target current value in the amplitude-variable proportional valve is determined, the current of the amplitude-variable proportional valve is controlled to be the target current value only through a preset controller, and then the flow area of the amplitude-variable balance valve can be maintained at the target flow area, so that the uniform amplitude falling of the crane at the target amplitude falling speed is ensured.

Of course, in other embodiments, the control may also implement real-time adjustment of the flow area of the variable amplitude balance valve by other means, so as to maintain the flow area of the balance valve in the target flow area state, for example, direct control by a dedicated controller, etc., which are not listed here.

According to the crane amplitude-varying control method, the relation between the load falling speed and the speed of the amplitude-varying oil cylinder, the flow of the amplitude-varying oil cylinder and the flow area of the amplitude-varying balance valve is calculated, so that the relation between the amplitude-varying angle of the large boom, the length of the large boom, the pressure of the rodless cavity and the input current of the amplitude-varying proportional valve is obtained in a constant-speed amplitude-varying state. Before the crane works, the relational formulas are input into the controller, and under the condition that the opening of the handle is not changed, the input current of the variable amplitude proportional valve is dynamically adjusted in real time through the large-arm variable amplitude angle, the large-arm length (such as large-arm total telescopic length) and the rodless cavity pressure which are fed back by the large arm of the crane in the amplitude falling process, so that the amplitude falling speed is ensured to be uniform and unchanged, and the stability and the safety of the amplitude falling of the crane are greatly improved.

The embodiment of the device is as follows:

based on the same inventive concept, the embodiment of the application also provides a crane amplitude control device, which comprises an acquisition module 1, a calculation control module 2 and a balance valve 3. As shown in fig. 6 and 7:

and the acquisition module 1 is used for acquiring the handle opening and working condition data of the crane.

The calculation control module 2 is used for determining a target amplitude falling speed based on the opening degree of the handle; and determining the target flow area of a balance valve of the crane based on the target amplitude falling speed and the working condition data, wherein the target flow area is the flow area of the balance valve 3 which can enable the crane to fall in amplitude at the target amplitude falling speed.

And the calculation control module 2 is also used for controlling the flow area of the balance valve 3 to be a target flow area so as to enable the crane to fall at a uniform speed at the target falling speed.

In other embodiments of the present application, the crane amplitude control device further includes a proportional valve 4, the proportional valve 4 is respectively connected to the calculation control module 1 and the balance valve 3, the calculation control module 2 controls the flow area of the balance valve 3 to be a target flow area by controlling the current of the proportional valve 4, and control is more conveniently achieved.

According to the crane amplitude control device provided by the embodiment of the application, the handle opening and working condition data of the crane are acquired through the acquisition module 1; then, by calculating the relationship between the amplitude variation angle and the length of the large boom, the pressure of the rodless cavity and the input current of the proportional valve 4, which are prestored in the control module 2, in the constant-speed amplitude falling state, and under the condition that the opening degree of the handle is not changed, the input current of the proportional valve 3 is dynamically adjusted in real time through the amplitude variation angle of the large boom, the length of the large boom (such as the total length of the large boom in extension and retraction) and the pressure of the rodless cavity fed back by the large boom of the crane in the amplitude falling process, so that the flow of the amplitude variation oil cylinder, which is the part above the balance valve 3 in fig. 7, is ensured, the amplitude falling speed is ensured to be uniform and unchanged, and the stability and the safety of the amplitude falling of the crane are greatly improved. And through the use of proportional valve, conveniently realize controlling.

The embodiment of the crane comprises:

based on the same inventive concept, the embodiment of the application also provides a crane, which comprises the crane amplitude control device provided by the device embodiment, and the crane amplitude control device is used for acquiring the handle opening and working condition data of the crane; and then according to the relationship between the amplitude variation angle of the large arm, the length of the large arm, the pressure of the rodless cavity and the input current of the amplitude variation proportional valve in the uniform amplitude falling state, under the condition that the opening degree of the handle is not changed, the input current of the amplitude variation proportional valve is dynamically adjusted in real time through the amplitude variation angle of the large arm, the length of the large arm (the total length of the large arm in extension and the like) and the pressure of the rodless cavity, which are fed back in the amplitude falling process of the large arm of the crane, so that the uniform amplitude falling speed is ensured to be unchanged, and the stability and the safety of the amplitude falling of the crane are greatly improved. And through the use of proportional valve, conveniently realize controlling.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A crane amplitude falling control method is characterized by comprising the following steps:

acquiring handle opening and working condition data of the crane;

determining a target amplitude falling speed based on the handle opening degree;

determining a target flow area of a balance valve of the crane based on the target amplitude falling speed and the working condition data, wherein the target flow area is the flow area of the balance valve which can enable the crane to fall in an amplitude manner at the target amplitude falling speed;

and controlling the flow area of the balance valve to be the target flow area so that the crane can drop the amplitude at the target amplitude dropping speed at a uniform speed.

2. The crane luffing control method according to claim 1, wherein the operating condition data includes a boom length, a boom luffing angle, crane structural parameters, and a luffing cylinder rodless cavity pressure of the crane.

3. The crane boom lowering control method according to claim 2, wherein said determining a target flow area of a balance valve of the crane based on the target boom lowering speed and the operating condition data comprises:

determining a target cylinder speed of a luffing cylinder of the crane based on the target luffing speed, the length of the large boom, the luffing angle of the large boom and the structural parameters of the crane; the target cylinder speed is the speed of the amplitude-variable cylinder which can enable the crane to drop the amplitude at the target amplitude-dropping speed uniformly;

determining the target rodless cavity flow of the variable amplitude oil cylinder based on the target oil cylinder speed; the flow of the target rodless cavity is the rodless cavity flow of the variable amplitude oil cylinder which can enable the variable amplitude oil cylinder to keep running at the speed of the target oil cylinder;

determining the target flow area based on the target rodless cavity flow and the pressure of the rodless cavity of the variable-amplitude oil cylinder; the target flow area is the flow area of the balance valve which can enable the variable amplitude oil cylinder to maintain the flow of the target rodless cavity.

4. The crane jib lowering control method according to claim 3, wherein the determining the target cylinder speed of the jib lubbing cylinder of the crane based on the target jib lowering speed, the jib length, the jib lubbing angle and the crane structural parameters comprises:

calculating to obtain the target oil cylinder speed according to a preset formula based on the target amplitude falling speed, the length of the large boom, the amplitude changing angle of the large boom and the structural parameters of the crane;

the preset formula comprises:

wherein, V ₂ For the target oil cylinder speed, A is the distance between the arm tail hinge point of the crane and the upper hinge point of the luffing oil cylinder, B is the distance between the arm tail hinge point of the crane and the lower hinge point of the luffing oil cylinder, and V ₁ And theta is the amplitude variation angle of the large arm of the crane, beta is the included angle between the horizontal line and the straight line where the tail hinge point of the arm of the crane and the lower hinge point of the amplitude variation oil cylinder are located, and L is the length of the large arm.

5. The crane jib landing control method of claim 2, wherein the crane structural parameters comprise a first distance and a second distance;

the first distance is the distance between the arm tail hinge point of the crane and the upper hinge point of the luffing oil cylinder, and the second distance is the distance between the arm tail hinge point of the crane and the lower hinge point of the luffing oil cylinder.

6. The crane boom lowering control method according to claim 1, wherein the controlling of the flow area of the balance valve to the target flow area includes:

and controlling the flow area of the balance valve to be kept at the target flow area through a proportional valve on the crane.

7. The crane jib control method of claim 6 wherein said controlling the flow area of the trim valve to remain at the target flow area via a proportional valve on the crane comprises:

determining a target current value of the proportional valve based on the target flow area; wherein the target current value is a current value of the proportional valve that can maintain a flow area of the balance valve at the target flow area;

and controlling the current of the proportional valve to be the target current value so as to enable the flow area of the balance valve to be the target flow area.

8. The crane amplitude control device is characterized by comprising an acquisition module, a calculation control module and a balance valve;

the acquisition module is used for acquiring the handle opening and working condition data of the crane;

the calculation control module is used for determining a target amplitude falling speed based on the handle opening degree; determining a target flow area of a balance valve of the crane based on the target amplitude falling speed and the working condition data, wherein the target flow area is the flow area of the balance valve which can enable the crane to fall in an amplitude manner at the target amplitude falling speed;

and the calculation control module is also used for controlling the flow area of the balance valve to be the target flow area so as to enable the crane to fall at the target falling speed and the uniform speed.

9. The crane banner control apparatus of claim 8, further comprising a proportional valve;

the proportional valve is respectively connected with the calculation control module and the balance valve;

and the calculation control module controls the flow area of the balance valve to be the target flow area by controlling the current of the proportional valve.

10. A crane comprising a crane jib control apparatus as claimed in any one of claims 8 to 9.

Images