Method, device, electronic device and storage medium for determining boom angular velocity

Abstract

The present invention relates to the field of hydraulic technology, and provides a method, device, electronic device and storage medium for determining the angular velocity of a boom. The method for determining the angular velocity of the boom is carried out according to the following steps: obtaining the angular velocity ω when the boom rotates, and the current angle parameter θ of the boom; calculating the theoretical flow rate Q flowing out of the rodless chamber of the oil cylinder based on the angular velocity ω and the angle parameter θ 缸 , that is, the flow rate Q flowing through the balance valve 缸 ; obtaining the pressure difference ΔP on both sides of the balance valve; determining the control current to be input to the solenoid valve based on the flow rate Q flowing through the balance valve 缸 , the pressure difference ΔP and the characteristics of the solenoid valve, and inputting the control current to the solenoid valve to control the boom to rotate at the angular velocity ω. The above technical solution solves the problem that the longer the boom is, the faster the angular velocity is. In the method for determining the angular velocity of the boom of the present invention, when the opening degree of the operation handle is the same, the longer the boom is, the smaller the angular velocity is, improving the safety of the working machine.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulics, and particularly to a method, device, electronic device and storage medium for determining the angular velocity of a boom. Background Art

[0002] In the boom amplitude-changing operations of concrete pumps, cranes, aerial work platforms, etc., the boom is usually driven by an oil cylinder. When the boom is lowering, generally, the self-weight of the boom is used to change the working angle of the boom, where the working angle refers to the angle between the boom and the horizontal plane. During the boom lowering process, due to the unstable lowering speed, the problem of boom shaking is likely to occur. To solve this problem, the operator controls the lowering speed of the boom by controlling the opening of the electro-hydraulic proportional valve at the pilot end of the balance valve. At the same handle opening, the longer the boom, the faster the angular velocity of the boom during lowering. However, the longer the boom, the lower the overall stiffness of the boom, and if the boom lowering speed is too high, safety problems are extremely likely to occur. Summary of the Invention

[0003] The present invention provides a method, device, electronic device and storage medium for determining the angular velocity of a boom, so as to solve the defect in the prior art that at the same handle opening, the longer the boom, the faster the boom lowering speed.

[0004] The present invention provides a method for determining the angular velocity of a boom. A construction machine has a boom and an oil cylinder connected to the boom. The control method is carried out according to the following steps: obtaining the angular velocity ω when the boom rotates and the current angle parameter θ of the boom; calculating the theoretically flow rate Q flowing out of the rodless cavity of the oil cylinder based on the angular velocity ω and the angle parameter θ 缸 , that is, the flow rate Q flowing through the balance valve 缸 ; obtaining the pressure difference △P on both sides of the balance valve; determining the control current to be input to the solenoid valve based on the flow rate Q 缸 flowing through the balance valve, the pressure difference △P and the characteristics of the solenoid valve, and inputting the control current to the solenoid valve to control the boom to rotate at the angular velocity ω.

[0005] According to the method for determining the angular velocity of a boom provided by the present invention, the step of obtaining the angular velocity ω when the boom rotates further includes: obtaining the output pressure P of the operation handle corresponding to the operation handle opening; the controller outputs the angular velocity ω of the boom rotation corresponding to the output pressure.

[0006] The present invention provides a method for determining the angular velocity of a boom. The step of the controller outputting the angular velocity ω of the boom rotation corresponding to the output pressure further includes: obtaining the real-time length L of the boom, the basic boom length L min and the maximum length L max of the boom; when the real-time length L = L minIn this case, the controller outputs the angular velocity ω of the boom rotation corresponding to the output pressure P.

[0007] The present invention provides a method for determining the angular velocity of a boom. The steps of the controller outputting the angular velocity ω of the boom rotation corresponding to the output pressure P further include: pre-acquiring the minimum output pressure of the operation handle and the first angular velocity corresponding to the minimum output pressure; pre-acquiring the maximum output pressure of the operation handle and the second angular velocity corresponding to the maximum output pressure; and obtaining the angular velocity ω of the boom rotation corresponding to the output pressure P based on the minimum output pressure, the maximum output pressure, the first angular velocity, and the second angular velocity.

[0008] The steps of the controller outputting the angular velocity ω of the boom rotation corresponding to the output pressure P further include: when the real-time length L = L max In this case, pre-acquiring the third angular velocity corresponding to the minimum output pressure of the operation handle; pre-acquiring the fourth angular velocity corresponding to the maximum output pressure of the operation handle; and obtaining the angular velocity ω of the boom rotation corresponding to the output pressure P based on the minimum output pressure, the maximum output pressure, the third angular velocity, and the fourth angular velocity.

[0009] The present invention provides a method for determining the angular velocity of a boom. The steps of the controller outputting the angular velocity ω of the boom rotation corresponding to the output pressure P further include: when the real-time length is within a preset interval (L min , L max ); the controller outputs the angular velocity ω of the boom rotation corresponding to the output pressure P.

[0010] The present invention provides a method for determining the angular velocity of a boom. The steps of the controller outputting the angular velocity ω of the boom rotation corresponding to the output pressure P further include: obtaining the fifth angular velocity of the boom rotation when the real-time length of the boom is acquired based on the first angular velocity, the third angular velocity, the basic boom length, and the maximum length; obtaining the sixth angular velocity of the boom rotation when the real-time length of the boom is acquired based on the second angular velocity, the fourth angular velocity, the basic boom length, and the maximum length; and the controller outputs the angular velocity ω of the boom rotation corresponding to the output pressure P based on the fifth angular velocity, the sixth angular velocity, the minimum output pressure, and the maximum output pressure.

[0011] An embodiment of the present invention further provides a boom angular velocity determination device, including: a pilot valve information acquisition module for acquiring the minimum output pressure and the maximum output pressure of the handle pilot valve; a boom length information acquisition module for acquiring the basic boom length, the real-time boom length, and the maximum boom length; a boom angular velocity determination module for determining the angular velocity of the boom rotation based on the minimum output pressure, the maximum output pressure, the basic boom length, the real-time boom length, and the maximum boom length of the pilot valve.

[0012] An embodiment of the present invention further provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor implements the boom angular velocity determination method as described above when executing the program.

[0013] An embodiment of the present invention further provides a non-transitory computer-readable storage medium, on which a computer program is stored, and the computer program implements the boom angular velocity determination method as described above when executed by a processor.

[0014] The boom angular velocity determination method provided by the present invention can calculate the input current value of the solenoid valve according to the hydraulic oil flow required by the rodless cavity of the oil cylinder during the boom lowering amplitude, so as to control the valve core opening of the balance valve. When the opening of the operation handle is the same, the longer the boom, the smaller the angular velocity, improving the safety of the working machine. Description of the Drawings

[0015] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0016] Figure 1 It is a schematic structural diagram when the crane is lifting the amplitude;

[0017] Figure 2 It is a schematic structural diagram when the crane is lowering the amplitude;

[0018] Figure 3 It is a schematic diagram of the control system of the construction machinery;

[0019] Figure 4 It is one of the identification diagrams of multiple data of the boom and the oil cylinder;

[0020] Figure 5 It is the second of the identification diagrams of multiple data of the boom and the oil cylinder;

[0021] Figure 6 It is a conventional boom angular velocity change trend diagram;

[0022] Figure 7 is the characteristic curve of the balance valve;

[0023] Figure 8 is the flow curve diagram of the balance valve when the hydraulic oil is at different temperatures;

[0024] Figure 9 is the schematic diagram of the physical structure of the electronic device provided by the present invention;

[0025] Reference numerals:

[0026] 10: oil cylinder; 20: balance valve; 21: throttle valve; 22: first one-way valve; 23: second one-way valve; 30: solenoid valve; 40: second reversing valve; 50: pilot valve; 61: servo pump; 62: hydraulic pump; 70: overflow valve; 81: first fuel tank; 82: second fuel tank; 90: pressure sensor; 100: controller; 910: processor; 920: communication interface; 930: memory; 940: communication bus. Detailed implementation manners

[0027] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without making creative efforts based on the embodiments in the present invention belong to the scope of protection of the present invention.

[0028] The terms "first" and "second" in the description and claims of the present invention may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0029] The following combines Figures 1-9 to describe the boom angular velocity determination method, device, electronic device and storage medium of the present invention.

[0030] The boom on the construction machinery is installed on the vehicle body, and the movement of the boom is driven by the movement of the vehicle body. For example, the boom of a concrete pump truck is folded and placed on the top of the vehicle body. The boom of an aerial work platform is folded and retracted between the boom sections and then placed on the vehicle body.

[0031] Such as Figure 1 and Figure 2As shown in the figure, the present invention takes a crane as an example. The length of the boom is variable and is achieved by the telescoping between multiple boom sections. The base end of the boom is connected to the vehicle body by a pin shaft. The oil cylinder 10 is connected between the oil cylinder hinge point below the boom and the oil cylinder hinge point on the vehicle body. During the working process, the luffing of the boom is achieved by the telescoping of the oil cylinder 10. That is, the change in the angle between the boom and the horizontal plane is achieved by the telescoping of the oil cylinder 10. In the present invention, this angle gradually increases during the lifting process and gradually decreases during the lowering process.

[0032] Since the base end of the boom is hinged to the vehicle body and the two ends of the oil cylinder 10 are respectively hinged to the boom and the vehicle body, when the boom naturally lowers (without actively controlling the hydraulic system of the oil cylinder 10), due to the self-weight of the boom applying a force to one end of the oil cylinder 10, the oil cylinder 10 will shorten and rotate simultaneously, thereby achieving a gradual decrease in the angle between the boom and the horizontal plane. During natural lowering, the angular velocity change trend diagram of the boom as shown in Figure 6 is drawn through test detection results. It can be seen from the figure that as time goes by, the angular velocity of the boom first gradually increases and then gradually decreases. However, in a period near the end of the lowering (when the angular velocity becomes 0), the angular velocity gradually increases and then rapidly decreases. This phenomenon is due to the fact that during the lowering process, the load on the oil cylinder 10 changes violently, causing the hydraulic system to generate an impact, resulting in the boom shaking. To avoid the impact, the boom can be controlled to lower at a constant angular velocity.

[0033] Therefore, a hydraulic system is designed. As shown in Figure 3 the figure, the hydraulic system includes an oil cylinder 10. A piston is arranged inside the oil cylinder 10. One end of the piston is connected with a cylinder rod, and one end of the cylinder rod passes through the top of the oil cylinder and extends to the outside. The piston divides the interior of the oil cylinder 10 into a rod chamber (between the side of the piston with the cylinder rod and the inner wall of the oil cylinder 10) and a rodless chamber. On the rod chamber side of the oil cylinder 10 in this hydraulic control system, it is communicated with a first oil tank 81 through a first oil circuit, and on the rodless chamber side, it is communicated with the first oil tank 81 through a second oil circuit. A hydraulic pump 62 is arranged on the second oil circuit. The hydraulic pump 62 pumps hydraulic oil to the rodless chamber side of the oil cylinder 10, so that the hydraulic oil in the rod chamber of the oil cylinder 10 flows into the first oil tank 81 through the first oil circuit, thereby causing the cylinder rod of the oil cylinder 10 to extend and realizing the lifting of the boom. During lowering, the hydraulic oil in the rodless chamber of the oil cylinder 10 flows out, resulting in a negative pressure in the rod chamber of the oil cylinder 10, so that the rod chamber side of the oil cylinder 10 sucks hydraulic oil from the first oil tank 81 through the first oil circuit. In order to protect the safety of the hydraulic system, the maximum pressure of the hydraulic system can be limited. That is, a relief valve (not shown in the figure) is arranged at the outlet of the hydraulic pump 62 to limit the pressure on the second oil circuit through the relief valve.

[0034] When the boom is lowered and the cylinder rod of the oil cylinder 10 moves towards the inside of the oil cylinder 10, a balance valve 20 is provided on the second oil path to control the flow rate of the hydraulic oil flowing out of the rodless cavity of the oil cylinder 10. Specifically, the balance valve 20 includes a first reversing valve, and the first reversing valve includes: a throttle valve 21 and a first check valve 22. The throttle valve 21 and the first check valve 22 are respectively located at different working positions of the first reversing valve. When the boom is raised, the first check valve 22 can be made to work, so that the hydraulic oil pumped out by the hydraulic pump 62 enters the rodless cavity of the oil cylinder 10 through the second oil path. The throttle valve 21 can also be made to work to control the flow rate and flow of the hydraulic oil flowing into the rodless cavity. When the boom is lowered, the first reversing valve switches to the working position where the throttle valve 21 is located, and the hydraulic oil flowing out of the rodless cavity passes through the throttle valve 21 into the first fuel tank 81. The switching of the working positions of the throttle valve 21 and the first check valve 22 in the first reversing valve is achieved by the cooperation of the pilot pressure and the spring. By changing the magnitude of the pilot pressure while the spring force acting on the spool remains unchanged, the position of the spool of the first reversing valve can be changed. When the boom is lowered, by changing the position of the spool of the first reversing valve, the flow rate of the hydraulic oil passing through the throttle valve 21 is controlled.

[0035] The pilot pressure is formed by the hydraulic oil acting on the pilot end of the first reversing valve. The pilot end of the first reversing valve is connected to the oil outlet of the servo pump 61. Further, to control the pilot pressure of the first reversing valve, a solenoid valve 30 is also provided between the servo pump 61 and the pilot end of the first reversing valve. For ease of control, the solenoid valve 30 can be selected as an electro-hydraulic proportional valve. The solenoid valve 30 is electrically connected to the controller 100. The controller 100 inputs a control signal to the solenoid valve 30, and the solenoid valve 30 responds to the control signal issued by the controller 100 to adjust the flow rate of the hydraulic oil passing through the solenoid valve 30. This control signal is used to control the spool position of the solenoid valve 30, thereby controlling the pilot pressure at the pilot end of the first reversing valve, further adjusting the spool position of the first reversing valve, and changing the flow rate passing through the first reversing valve. That is, when the boom is lowered, the flow rate of the hydraulic oil passing through the balance valve 20 is changed by the solenoid valve 30.

[0036] Changing the flow rate of the hydraulic oil of the balance valve 20 can further adjust the moving speed of the piston and the cylinder rod in the oil cylinder 10. And from Figure 1 、 Figure 2 it can be seen that the cylinder rod of the oil cylinder 10 is connected to the boom, and the moving speed of the cylinder rod in the oil cylinder 10 will affect the speed of the boom when it is lowered, which is hinged to the cylinder rod.

[0037] In addition, the oil outlet of the servo pump 61 is connected to an overflow valve 70 with a limited pressure. Through the overflow valve 70, part of the hydraulic oil pumped out by the servo pump 61 can be introduced into the second fuel tank 82. The first fuel tank 81 and the second fuel tank 82 can be the same fuel tank.

[0038] Furthermore, in order to increase the variation range of the hydraulic oil passing through the balancing valve 20, a second one-way valve 23 is set in the second oil circuit. The second one-way valve 23 is connected in parallel with the first reversing valve. The hydraulic oil pumped out by the hydraulic pump 62 can enter the rodless chamber of the cylinder 10 through the first one-way valve 22 and the second one-way valve 23.

[0039] Furthermore, in order to control the flow rate and velocity of the hydraulic oil in the second oil circuit between the hydraulic pump 62 and the rodless chamber of the oil cylinder 10, a second reversing valve 40 is provided in the oil circuit, and the flow rate and velocity of the hydraulic oil passing through the second reversing valve 40 can be controlled by controlling the position of the valve core in the second reversing valve 40. The second reversing valve 40 has a plurality of working positions, and in one of the working positions, the hydraulic oil flowing out of the rodless chamber of the oil cylinder 10 can be directly fed into the first oil tank 81 without passing through the hydraulic pump 62.

[0040] Furthermore, a pilot valve 50 is connected between the pilot ends on both sides of the second reversing valve 40 and the servo pump 61. The pilot valve 50 is connected to an operating handle, and the operating handle can move in the left and right directions (the operator is sitting in the cab, the left and right of the driver), and the left and right directions of the operating handle correspond to the pilot ends on both sides of the second reversing valve 40. If the operating handle moves to the left, the oil circuit between the corresponding servo pump 61 and the pilot end on the left side of the second reversing valve 40 is connected, thereby controlling the movement of the valve core in the second reversing valve 40. The amplitude and direction of the operation of the operating handle will correspondingly cause a pressure change between the pilot valve 50 and the pilot end of the second reversing valve 40, that is, the operator's action information is converted into pressure change information. Normally, the handle is located in the middle position. The operating handle can be set in the cab on the vehicle body.

[0041] Furthermore, in order to monitor the change of the pressure in the oil circuit between the pilot valve 50 and the pilot end of the second reversing valve 40 in real time, a pressure sensor 90 is provided, and the pressure of the oil circuit can be displayed in real time through the pressure sensor 90.

[0042] When the increase Figure 3 As shown, the hydraulic pump 62 pumps oil from the first oil tank 81, the second reversing valve 40 is switched to the right position, and the hydraulic oil enters the oil cylinder 10 through the first check valve 22 and / or the second check valve 23 in the balance valve 20, and finally controls the extension of the cylinder rod in the oil cylinder 10. From the above analysis, it can be seen that when the boom is raised, the speed of the boom is controlled by the displacement and speed of the hydraulic pump 62.

[0043] At the end of the lowering stroke, when the pilot valve 50 is opened, the pressure sensor 90 transmits the detected pressure value to the controller 100, and this pressure value corresponds to the opening of the operating handle. The greater the opening, the faster the boom descends, and the smaller the opening, the slower the boom descends. When the boom length is fixed, the opening of the handle is positively correlated with the angular velocity of the boom. A boom length sensor for monitoring the boom length is provided on the boom. For example, this boom length sensor can be a displacement sensor. As can be seen from Table 1:

[0044] Table 1 Relationship diagram of the lowering speed and the boom length

[0045]

[0046] In Table 1, the minimum output pressure of the operating handle is 5 bar, and the maximum output pressure is 25 bar. It can be understood that for different operating handles, the minimum output pressure value and the maximum output pressure value are different.

[0047] Specifically, a three-dimensional coordinate system can be established based on the real-time length L of the boom, the output pressure P of the operating handle, and the angular velocity ω when the boom rotates. In this embodiment, the boom is a telescopic boom, so the minimum length of the boom is set as L min , and the maximum length of the boom is L max . In an embodiment of the present invention, the length of the basic boom is selected as 15 m. When the length of the boom is less than 15 m, the overall stiffness of the boom remains unchanged. Therefore, when the real-time length of the boom is the minimum length, the calculation of the angular velocity ω is performed based on the boom length of 15 m. As can be seen from Table 1, when the minimum output pressure of the operating handle is 5 bar, ω1 = 0.8° / s; when the maximum output pressure of the operating handle is 25 bar, ω2 = 1.0° / s. At this time, when the output pressure of the operating handle is P, the angular velocity of the boom rotation is:

[0048] ω = ω1 + (ω2 - ω1) * (P - 5) / (25 - 5).

[0049] When the boom length is equal to the maximum length, when the minimum output pressure of the operating handle is 5 bar, ω3 = 0.2° / s; when the maximum output pressure of the operating handle is 25 bar, ω4 = 0.4° / s.

[0050] At this time, when the output pressure of the operating handle is P, the angular velocity of the boom rotation is:

[0051] ω = ω3 + (ω4 - ω3) * (P - 5) / (25 - 5).

[0052] When the boom length L max > L > L min When, ω1, ω3, and the minimum length L can be used first minand the maximum length L max When the boom length is the real-time length, calculate the angular velocity ω5 of the boom rotation; then use ω2, ω4, the minimum length L min and the maximum length L max When the boom length is the real-time length, calculate the angular velocity ω6 of the boom rotation. Through ω5, ω6, the maximum output pressure, and the minimum output pressure, when the controller calculates that the output pressure of the operating handle is P, calculate the angular velocity ω of the boom rotation. Specifically, the calculation formulas for ω5, ω6, and ω are as follows:

[0053] ω5 = ω1 + (ω3 - ω1) * (L - L min ) / (L max - L min );

[0054] ω6 = ω2 + (ω4 - ω2) * (L - L min ) / (L max - L min );

[0055] ω = ω5 + (ω6 - ω5) * (P - 5) / (25 - 5).

[0056] According to Table 1 and the above calculation formulas, it can be known that: when the boom length is the same, the greater the pressure of the operating handle, the greater the angular velocity ω; when the output pressure of the operating handle is the same, the longer the boom length, the smaller the angular velocity ω. In this embodiment, since the pilot valve 50 of the operating handle is a pressure reducing valve, the influence of temperature change on the pilot valve 50 can be ignored. That is, when the opening of the operating handle is the same, the values measured by the pressure sensor 90 are the same.

[0057] It should be noted that: in the above table, the values of ω1, ω2, ω3, and ω4 are schematic, only for explaining the relationship between the lowering speed and the boom length.

[0058] Set an angle sensor on the boom to transmit the detected boom angle (the angle between the boom and the horizontal plane) to the controller 100. Then, through the angular velocity of the boom rotation input to the controller 100, the geometric parameters of the oil cylinder 10 (the cross-sectional diameter of the oil cylinder), and the boom angle, the theoretical flow rate of the rodless cavity of the current oil cylinder 10 can be calculated. The current flow rate of the rodless cavity of the oil cylinder 10 refers to the flow rate through the rodless cavity, or the flow rate of the hydraulic oil flowing from the rodless cavity through the balance valve 20 into the first oil tank 81. The phenomenon of mismatched balance flow rates of the oil cylinder is eliminated, and the boom is lowered at a constant angular velocity.

[0059] A pre-valve pressure sensor (not shown in the figure) is provided between the balance valve 20 and the oil cylinder 10, and a post-valve pressure sensor (not shown in the figure) is provided between the balance valve 20 and the first reversing valve. By calculating the difference between the pre-valve pressure sensor and the post-valve pressure sensor, the pressure difference ΔP before and after the balance valve 20 can be calculated.

[0060] The existing balance valve control method is to directly input a control current to the solenoid valve 30 through a handle, thereby controlling the opening of the spool of the solenoid valve 30, and then controlling the flow rate through the balance valve 20, that is, the flow rate of the rodless cavity. The falling speed of the boom is controlled by controlling the flow rate through the balance valve 20. In an ideal situation, when the boom falls to a stop, the opening of the operating handle decreases (the operating handle will gradually approach the middle position), and the angular velocity of the boom will decrease accordingly. However, with this control method, during the process of falling to a stop, especially when the boom is approaching a stop, the angular velocity will rapidly increase and then rapidly decrease to zero. The above changes in angular velocity can make the operator clearly feel a sense of impact, resulting in a poor operating experience. The direct factors causing this phenomenon include the self-weight of the boom, the load on the hook, the length of the boom, the oil temperature of the hydraulic oil, etc. The operator needs to consider the above factors and then input a control current to the solenoid valve 30 through the operating handle. Usually, an experienced operator will operate according to actual operating experience, but one or several factors may be overlooked, resulting in a poor controllability experience. And the controllability experienced by an inexperienced operator will be even worse.

[0061] In the present invention, by providing a solenoid valve, a balance valve, a control valve group, a plurality of sensors and a controller, the input current value of the solenoid valve can be calculated according to the flow rate of the hydraulic oil flowing out of the rodless cavity of the oil cylinder when the boom falls, thereby controlling the opening of the spool of the balance valve, realizing the boom falling at a constant angular velocity. When the opening of the operating handle is the same, the longer the boom, the smaller the angular velocity, improving the safety of the working machine.

[0062] The embodiment of the present invention also provides a method for determining the angular velocity of the boom, which specifically includes the following steps:

[0063] Step 01: Obtain the angular velocity ω when the boom rotates and the current angle parameter θ of the boom; Step 02: Based on the angular velocity ω and the angle parameter θ, obtain the theoretically flowing-out flow rate Q of the rodless cavity of the oil cylinder 缸 , that is, the flow rate Q flowing through the balance valve 缸 ; Step 03: The controller obtains the pressure difference ΔP on both sides of the balance valve; Step 04: Based on the flow rate Q flowing through the balance valve 缸 , the pressure difference ΔP, and the characteristics of the solenoid valve, determine the control current to be input to the solenoid valve, and input the corresponding control current to the solenoid valve to control the boom to rotate at the angular velocity ω.

[0064] Now Figure 1 、 Figure 2The hinge points between the construction machinery oil cylinder, the boom and the vehicle body, and the connection between the oil cylinder and the boom are simplified into a model as shown in Figure 4 . In this model, the length of the line connecting the hinge point between the boom and the vehicle body and the hinge point between the oil cylinder and the vehicle body is set as b (a fixed value), the real-time length of the boom is set as L, the real-time length of the oil cylinder 10 is set as a, the distance between the hinge point of the oil cylinder 10 and the boom and the hinge point of the boom and the vehicle body is set as c (a fixed value), the angle between the oil cylinder 10 and the boom is α, the angle between the direction perpendicular to the boom at the hinge point of the oil cylinder 10 and the oil cylinder 10 is set as β, the angle between the boom and the horizontal plane is set as ψ, and the angle between b and c is set as θ.

[0065] Furthermore, the angular velocity ω calculated according to the above formula is the real-time angular velocity of the boom. By measuring ψ in real time with an angle sensor, and the angle between b and the horizontal plane is a fixed value, so the angle θ between the boom and this line can be obtained in real time. The velocity V1 at the hinge point of the oil cylinder 10 and the boom = ω·c. And V 缸 = V1·cos(β) = V1·sin(α), that is, sin(α) = b·sin(θ) / a. According to the cosine theorem, the real-time length of the oil cylinder 10 Thus, it can be obtained that

[0066]

[0067] And the flow rate Q of the rodless cavity of the oil cylinder 10 缸 = V 缸 ·A (where A is the cross-sectional area of the oil cylinder, which is a fixed value), that is, the theoretical flow rate Q of the rodless cavity 缸 (the flow rate passing through the balance valve) can be obtained according to the real-time angle θ and the angular velocity value ω.

[0068] The pressure difference △P detected by the pre-valve pressure sensor and the post-valve pressure sensor is input into the controller 100, and the characteristic curve graph of the balance valve 20 is obtained in advance. This characteristic curve graph is as shown in Figure 7 . Figure 7 It has multiple lines, representing the change relationship curves between the flow rate of the balance valve under the pilot pressure and the balance valve pressure difference. However, the data measured in advance is limited and cannot include all data. When determining the flow rate Q 缸 of the balance valve and the pressure difference △P, the coordinate point may fall between two curves. Therefore, the interpolation method is used between adjacent two curves to determine the pilot pressure, so as to reduce the error between the obtained pilot pressure and the actual pilot pressure and improve the accuracy.

[0069] From this characteristic curve, the pilot pressure can be found out at the determined pressure difference △P and the determined theoretical flow rate Q of the rodless cavity 缸The pilot pressure at the pilot end of the lower balance valve 20. Based on the pre-obtained corresponding relationship between the pilot pressure of the balance valve 20 and the control current of the solenoid valve 30, the magnitude of the current to be input into the controller 100 can be adjusted. The included angle θ can be measured in real time by an angle sensor on the boom and input into the controller. The pressure difference △P can be measured by pressure sensors arranged before and after the balance valve 20 in real time. Therefore, according to the rotation of the boom, the real-time pressure required at the pilot end of the balance valve 20 can be obtained in real time, and the magnitude of the current input into the solenoid valve 30 can be regulated according to the real-time pressure. It reduces the manual intervention and judgment process of the operator, that is, reduces the possibility of human error and improves the controllability of the hydraulic control system. At the same time, it can be seen from the above formula derivation process that the direct factors affecting the boom speed control, such as the length of the boom, the load of the hook, and the self-weight of the boom, are converted into the fundamental influencing factors, that is, the real-time included angle θ of the boom and the constant angular velocity value ω.

[0070] The controller 100 obtains the required pilot pressure at the pilot end of the balance valve 20 by inputting the theoretically Q 缸 (flow rate of the rodless chamber) and the pressure difference △P by looking up a table method. There is a corresponding relationship between the pilot pressure at the pilot end of the balance valve 20 and the current input by the controller 100 to the solenoid valve 30. For example, when the solenoid valve 30 uses an electro-hydraulic proportional reducing valve, according to the characteristics of the electro-hydraulic proportional reducing valve, the corresponding relationship between the pilot pressure and the input current can be obtained.

[0071] Further, an oil temperature sensor ( Figure 3 (not shown) is arranged on the oil circuit between the rodless chamber and the balance valve 20. This oil temperature sensor can detect the temperature of the hydraulic oil in the oil circuit. Since the temperature of the hydraulic oil in the hydraulic control system will rise during actual use. The temperature change of the hydraulic oil will affect the viscosity of the hydraulic oil. The higher the temperature, the lower the viscosity of the hydraulic oil. By pre-testing the characteristics of the balance valve 20 at different temperatures, such as the first preset temperature and the second preset temperature. The test data are shown in Figure 8 , and the result is that the balance valve 20 is greatly affected by the temperature change. Optionally, in this embodiment, the first preset temperature is 30 °C and the second preset temperature is 50 °C.

[0072] Therefore, the balance valve 20 is pre-tested at different temperatures to obtain multiple Figure 7 . When actually looking up the corresponding table, first lock multiple Figure 7One of them, and then based on the measured △P in real time and the flow rate of the rodless chamber in theory (the flow rate passing through the balance valve 20), find the pilot pressure corresponding to the pilot end of the balance valve 20. Based on the corresponding relationship between the control current input from the controller 100 to the solenoid valve 30 and the change in the pressure at the pilot end of the balance valve 20 measured in advance, obtain the control current required for the solenoid valve 30. This process takes into account the temperature in advance during the process of obtaining the control current, so it can avoid the influence of temperature change on the rotation speed of the boom at the same handle opening.

[0073] Furthermore, the present invention can achieve the constant angular velocity rotation of the boom. Just input the expected angular velocity value ω to the controller through the opening of the handle, and the boom can rotate at the expected angular velocity value ω. Of course, the expected angular velocity value ω input to the controller can also be adjusted periodically as needed to achieve the variable angular velocity rotation of the boom.

[0074] Furthermore, the present invention can achieve the constant speed amplitude reduction of the boom head in the vertical direction. According to V 臂 = V·cosψ = ω·L·cosψ, it can be obtained that ω = V 臂 / L·cosψ. That is, to achieve the constant speed amplitude reduction of the boom head in the vertical direction, the real-time ω is calculated. Then, according to Q 缸 = V 缸 ·A, and

[0075]

[0076] At a certain temperature, when the controller 100 expects V 臂 to be constant, the Q of the balance valve 20 can be calculated. 缸 Then, according to the above-mentioned characteristic table of the balance valve 20 obtained in advance, find the pilot pressure at the pilot end of the balance valve 20, and obtain the current that the controller 100 needs to input to the solenoid valve 30.

[0077] Furthermore, by controlling the Q 缸 flowing through the balance valve 20, when the boom amplitude reduction is approaching the stop state, the angular velocity of the boom will not change suddenly, and the boom will not vibrate.

[0078] The embodiment of the present invention also provides a construction machinery, including a vehicle body, a boom arranged on the vehicle body, and a control system of the construction machinery to control the boom to rotate at a constant angular velocity or the end of the boom to rotate at a constant speed in the vertical direction.

[0079] For the construction machinery provided by the embodiment of the present invention, when the opening of the operation handle is the same, the longer the boom, the smaller the angular velocity, which improves the safety of the working machinery.

[0080] An embodiment of the present invention further provides a boom angular velocity determination device, including: a pilot valve information acquisition module, configured to acquire the minimum output pressure and the maximum output pressure of the handle pilot valve 50; a boom length information acquisition module, configured to acquire the basic boom length, the real-time boom length, and the maximum boom length; a boom angular velocity determination module, configured to determine the angular velocity of the boom rotation based on the minimum output pressure, the maximum output pressure, the basic boom length, the real-time boom length, and the maximum boom length of the pilot valve 50.

[0081] As Figure 9 shown, an embodiment of the present invention further provides an electronic device, which may include: a processor 910, a communication interface 920, a memory 930, and a communication bus 940. Among them, the processor 910, the communication interface 920, and the memory 930 complete mutual communication through the communication bus 940. The processor 910 may call the logical instructions in the memory 930 to execute the boom angular velocity determination method.

[0082] It should be noted that the electronic device in this embodiment may be a server, a PC, or other devices when specifically implemented, as long as its structure includes a processor 910, a communication interface 920, a memory 930, and a communication bus 940 as Figure 9 shown. Among them, the processor 910, the communication interface 920, and the memory 930 complete mutual communication through the communication bus 940, and the processor 910 may call the logical instructions in the memory 930 to execute the above method. The specific implementation form of the electronic device in this embodiment is not limited.

[0083] In addition, when the logical instructions in the above-mentioned memory 930 are implemented in the form of a software functional unit and sold or used as an independent product, they may be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, may be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media such as a USB flash drive, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk, or an optical disc that can store program codes.

[0084] On the other hand, the present invention also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute the boom angular velocity determination method provided by each of the above methods. The method includes: obtaining the angular velocity ω when the boom rotates, and the current angle parameter θ of the boom; calculating the theoretically flow rate Q of the oil flowing out of the rodless chamber of the oil cylinder based on the angular velocity ω and the angle parameter θ 缸 , that is, the flow rate Q flowing through the balance valve 缸 ; obtaining the pressure difference △P on both sides of the balance valve; determining the control current to be input to the solenoid valve based on the flow rate Q flowing through the balance valve 缸 , the pressure difference △P, and the characteristics of the solenoid valve, and inputting the control current to the solenoid valve to control the boom to rotate at the angular velocity ω.

[0085] On another aspect, the present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it realizes the boom angular velocity determination method provided by each of the above. The method includes: obtaining the angular velocity ω when the boom rotates, and the current angle parameter θ of the boom; calculating the theoretically flow rate Q of the oil flowing out of the rodless chamber of the oil cylinder based on the angular velocity ω and the angle parameter θ 缸 , that is, the flow rate Q flowing through the balance valve 缸 ; obtaining the pressure difference △P on both sides of the balance valve; determining the control current to be input to the solenoid valve based on the flow rate Q flowing through the balance valve 缸 , the pressure difference △P, and the characteristics of the solenoid valve, and inputting the control current to the solenoid valve to control the boom to rotate at the angular velocity ω.

[0086] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated. The components shown as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative labor.

[0087] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on such an understanding, the above technical solution, in essence, or the part that contributes to the prior art can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for determining the angular velocity of a boom. The construction machinery has a boom and an oil cylinder connected to the boom. It is characterized in that The method for determining the boom angular velocity is carried out according to the following steps: Obtain the output pressure P of the operating handle corresponding to the opening of the operating handle. The controller outputs the angular velocity ω of the boom rotation corresponding to the output pressure, and obtain the current angle parameter θ of the boom; Calculate the velocity V of the oil cylinder based on the angular velocity ω and the angle parameter θ 缸 , based on the velocity V of the oil cylinder 缸 and the cross-sectional area of the oil cylinder, calculate the theoretically flowing-out flow rate Q of the oil cylinder from the rodless cavity 缸 , that is, the flow rate Q flowing through the balance valve 缸 ; Obtain the pressure difference △P on both sides of the balance valve; Based on the characteristic curve of the balance valve and the flow rate Q flowing through the balance valve 缸 and the pressure difference △P, the pilot pressure at the pilot end of the balance valve is obtained. Based on the corresponding relationship between the pilot pressure and the control current of the solenoid valve, the control current to be input to the solenoid valve is determined, and the control current is input to the solenoid valve to control the boom to rotate at the angular velocity ω; Wherein, the step of the controller outputting the angular velocity ω of the boom rotation corresponding to the output pressure further includes: obtaining the real-time length L of the boom, the basic boom length L min and the maximum length L of the boom max ; when the real-time length L = L min , the controller outputs the angular velocity ω of the boom rotation corresponding to the output pressure P; The step that the controller outputs the angular velocity ω of the boom rotation corresponding to the output pressure P further includes: When the real-time length L = L min , the minimum output pressure of the operating handle and the first angular velocity ω1 corresponding to the minimum output pressure are obtained in advance; Pre-obtain the maximum output pressure of the operating handle and the second angular velocity ω2 corresponding to the maximum output pressure; Based on the following formula, obtain the angular velocity ω of the boom rotation corresponding to the output pressure P, ω = ω1 + (ω2 - ω1) * (P - 5) / (25 - 5).

2. The method for determining the angular velocity of the boom according to claim 1, wherein The step that the controller outputs the angular velocity ω of the boom rotation corresponding to the output pressure P further includes: When the real-time length L = L max , the third angular velocity ω3 corresponding to the minimum output pressure of the operating handle is obtained in advance, and the third angular velocity ω3 is less than the first angular velocity ω1; Pre-obtain the fourth angular velocity ω4 corresponding to the maximum output pressure of the operating handle, and the fourth angular velocity ω4 is greater than the second angular velocity ω2; Based on the following formula, obtain the angular velocity ω of the boom rotation corresponding to the output pressure P, ω = ω3 + (ω4 - ω3) * (P - 5) / (25 - 5).

3. The method for determining the angular velocity of the boom according to claim 2, characterized in that, The step that the controller outputs the angular velocity ω of the boom rotation corresponding to the output pressure P further includes: When the real-time length is within a preset interval (L min , L max ); The controller outputs the angular velocity ω of the boom rotation corresponding to the output pressure P.

4. The method for determining the angular velocity of the boom according to claim 3, characterized in that, The step that the controller outputs the angular velocity ω of the boom rotation corresponding to the output pressure P further includes: Based on the first angular velocity ω1, the third angular velocity ω3, the basic boom length, and the maximum length, when obtaining the real-time length of the boom, obtain the fifth angular velocity ω5 of the boom rotation; Based on the second angular velocity ω2, the fourth angular velocity ω4, the basic boom length, and the maximum length, when obtaining the real-time length of the boom, obtain the sixth angular velocity ω6 of the boom rotation; Based on the following formula, obtain the angular velocity ω of the boom rotation corresponding to the output pressure P output by the controller, ω = ω5 + (ω6 - ω5) * (P - 5) / (25 - 5).

5. An arm angular velocity determination device, characterized in that, It includes: A pilot valve information acquisition module, which acquires the minimum output pressure and the maximum output pressure of the handle pilot valve; A boom length information acquisition module, which is used to acquire the basic boom length, the real-time length of the boom, and the maximum length of the boom; A boom angular velocity determination module, which determines the angular velocity of the boom rotation based on the minimum output pressure, the maximum output pressure, the basic boom length, the real-time length of the boom, and the maximum length of the boom. Specifically: When the real-time length L = L min in this case, the minimum output pressure of the operating handle and the first angular velocity ω corresponding to the minimum output pressure are obtained in advance 1， the maximum output pressure of the operating handle and the second angular velocity ω corresponding to the maximum output pressure are obtained in advance 2， the angular velocity ω of the boom rotation corresponding to the output pressure P is obtained based on the following formula ω = ω1 + (ω2 - ω1) * (P - 5) / (25 - 5).

6. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the boom angular velocity determination method according to any one of claims 1 to 4.

7. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the boom angular velocity determination method according to any one of claims 1 to 4.

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