A method and system for floating control of a grapple boom

Abstract

The present application relates to the technical field of grab machine, and provides a grab machine movable arm floating control method and system, wherein the required pressure for supporting the posture of the grab machine is calculated by measuring the structural parameters of the grab machine and the posture inclination angles of the movable arm and the bucket rod acquired in real time, the movable arm oil cylinder pressure is adjusted, the movable arm is lifted while the grab bucket is closed, the collision damage caused by the excessive force between the grab bucket and the material supporting surface is avoided, the safety of operation is improved, the situation that the material grabbed by the grab bucket is not clean is solved, and the loading and unloading efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of material handling machine technology, and more specifically, to a method and system for controlling the floating motion of a material handling boom. Background Technology

[0002] Material grabbers are widely used in bulk material loading and unloading operations at railway stations, ports, and docks. However, during their use, the grabber buckets often cause varying degrees of collision and damage to the bottom surface of the material pile, resulting in high maintenance costs and safety hazards. To reduce collisions with the bottom surface, experienced material grabber operators usually control the grabber buckets at a certain distance from the bottom surface of the material pile before grabbing the material. However, this method is difficult to control, results in incomplete grabbing and unloading, and has low operating efficiency. Summary of the Invention

[0003] The purpose of this invention is to provide a floating control method and system for a material handling boom, thereby solving the aforementioned technical problems.

[0004] The embodiments of the present invention are achieved through the following technical solution: a method for controlling the floating of a grabbing boom, the grabbing machine including a boom and a stick that are hinged to each other, the boom being hinged to a fixed end face, and a boom cylinder connected to the boom for controlling the boom pitch angle, the stick being hinged to a grab bucket, characterized in that it includes: measuring the structural parameters of the grabbing machine, acquiring the boom attitude tilt angle α and the stick attitude tilt angle b in real time, calculating the pressure P1 required to support the attitude of the grabbing machine based on the structural parameters, the boom attitude tilt angle α and the stick attitude tilt angle b, setting the constant pressure borne by the bottom surface of the material to P0, closing the grab bucket, and simultaneously adjusting the boom cylinder pressure to P, where P = P1 - P0.

[0005] Furthermore, the hinge point between the boom and the fixed end face is A, the hinge point between the boom and the stick is B, the hinge point between the stick and the grab bucket is C, the hinge point between the boom cylinder and the fixed end face is D, and the hinge point between the boom cylinder and the boom is E. The structural parameters include the large cavity area S of the boom cylinder, the boom weight G1, the stick weight G2, the grab bucket weight G3, the length L11 of the line connecting hinge points A and B, the length L1` of the line connecting hinge point A and the boom center of mass and the angle a` between the line connecting hinge points A and B, the length L6 of the line connecting hinge points A and E, the length L5 of the line connecting hinge points A and D and the angle c with the horizontal plane, the length L22 of the line connecting hinge points B and C, the length L2` of the line connecting hinge point B and the stick center of mass and the angle b` between the line connecting hinge points B and C.

[0006] Furthermore, the expression for the pressure P1 required to support the posture of the gripper is: .

[0007] A floating control system for a grab boom includes a control valve, a float switch, and an electronic controller. The control valve is used to change the working posture of the boom, stick, and grab bucket. The float switch is used to enable simultaneous operation of the boom and grab bucket. The input terminals of the electronic controller are electrically connected to a first sensor for detecting the boom tilt angle α and a second sensor for detecting the stick tilt angle β, respectively. The output terminal is electrically connected to an electro-proportional relief valve for changing the pressure value of the boom cylinder.

[0008] Furthermore, the control valves include a boom handle valve, a stick handle valve, a grab handle valve, and a multi-way valve. The pilot oil sources of the boom handle valve, stick handle valve, and grab handle valve are respectively connected to the corresponding pilot oil ports of the multi-way valve. By operating the boom handle valve, the main pump oil source acts on the boom cylinder through the working oil port of the multi-way valve. By operating the stick handle valve, the main pump oil source is connected to the stick cylinder through the working oil port of the multi-way valve. By operating the grab handle valve, the main pump oil source is connected to the grab cylinder through the working oil port of the multi-way valve.

[0009] Furthermore, the floating switch is connected to a solenoid valve, which can control the simultaneous activation of the main pump oil supply to the boom cylinder and the grab cylinder.

[0010] The present invention has at least the following advantages and beneficial effects: by measuring the structural parameters of the grabber and combining the real-time acquired attitude and tilt angles of the boom and stick, the pressure required to support the attitude of the grabber is calculated, and the pressure of the boom cylinder is adjusted to realize the lifting of the boom while closing the grab, thus avoiding excessive force between the grab and the bottom surface of the material bearing and causing collision damage, improving the safety of operation, and also solving the problem of the grabber not grabbing the material cleanly, thus improving the loading and unloading efficiency. Attached Figure Description

[0011] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 A flowchart illustrating a floating control method for a material handling boom provided by the present invention; Figure 2 A schematic diagram of a floating control system for a material handling boom provided by the present invention; Figure 3 A schematic diagram of the structural parameters of the material handling machine in a floating control system for a material handling boom provided by the present invention; Icons: 1-Grab, 2-Boom, 21-Boom cylinder, 3-Stick, 31-Stick cylinder, 4-Grab bucket, 41-Grab cylinder, 5-Control valve, 51-Boom handle valve, 52-Stick handle valve, 53-Grab handle valve, 54-Multi-way valve, 6-Floating switch, 61-Solenoid valve, 7-Electrical controller, 71-First sensor, 72-Second sensor, 73-Electro-proportional relief valve. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0014] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0015] Example This invention provides a method for controlling the floating boom of a material grabber 1. The material grabber 1 includes a boom 2 and a stick 3 that are hinged together. The boom 2 is hinged to an existing fixed end face, and a boom cylinder 21 for controlling the pitch angle of the boom 2 is also connected to the boom 2. A grab bucket 4 is hinged to the stick 3. Figure 3 As shown, the hinge point between boom 2 and the fixed end face is A, the hinge point between boom 2 and stick 3 is B, the hinge point between stick 3 and grab bucket 4 is C, the hinge point between boom cylinder 21 and the fixed end face is D, and the hinge point between boom cylinder 21 and boom 2 is E. Figure 1 As shown, the floating control method for the boom 2 of the material handling machine 1 includes the following steps: Step 1: Measure the structural parameters of the material handling machine 1.

[0016] Furthermore, in specific implementation, such as Figure 3As shown, the structural parameters provided in this embodiment of the invention include the large cavity area S of the boom cylinder 21, the weight G1 of the boom 2, the weight G2 of the stick 3, the weight G3 of the grab bucket 4, the length L11 of the line connecting hinge points A and B, the length L1' of the line connecting hinge point A and the center of mass of boom 2 and the angle a' with the line connecting hinge points A and B, the length L6 of the line connecting hinge point A and E, the length L5 of the line connecting hinge point A and D and the angle c with the horizontal plane, the length L22 of the line connecting hinge points B and C, and the length L2' of the line connecting hinge point B and the center of mass of stick 3 and the angle b' with the line connecting hinge points B and C. It should be noted that the structural parameters of the grabber 1 can be obtained before the unloading operation. The same equipment only needs to be measured and obtained once, and subsequent operations will use them as known parameters. In addition, as Figure 3 In the diagram, G1, G2, and G3 can represent the positions of the center of mass of boom 2, stick 3, and grab bucket 4, respectively.

[0017] Step 2: Obtain the boom 2 attitude tilt angle 'a' and stick 3 attitude tilt angle 'b' in real time.

[0018] Step 3: Calculate the pressure P1 required to support the posture of the grabber 1 based on the structural parameters, the tilt angle a of boom 2 and the tilt angle b of stick 3; Furthermore, in practical implementation, the formula is used: (1) Calculate the horizontal distance L1 from hinge point A to the center of mass G1 of boom 2, and then use the formula: (2) Calculate the horizontal distance L2 from hinge point A to the center of mass G2 of stick 3, and then use the formula: (3) Calculate the horizontal distance L3 from hinge point A to the center of mass G3 of grab bucket 4, and then use the formula: (4) Calculate the lever arm L4 of boom cylinder 21 about hinge point A, and take the moment about hinge point A. The formula is: (5) Substituting equations (1), (2), (3), and (4) into equation (5), we obtain the expression for the pressure P1 required to support the material handling machine 1 in any posture: .

[0019] That is, when the grab bucket 4 does not touch the bottom surface of the material, applying pressure P1 to the boom cylinder 21 can achieve the suspension balance of the grab machine 1 in any posture.

[0020] Step 4: Set the constant pressure on the bottom surface of the material-bearing machine to P0. The operator of the grabber 1 can set this according to the actual material being loaded and unloaded. For example, if the bottom surface of the material-bearing machine has weak structural strength and is easily damaged, a smaller constant pressure P0 can be selected, that is, the bottom surface of the material-bearing machine bears part of the pressure P0 of the grabber 4. At this time, the grabber 4 is also subjected to the reaction support force P0 of the bottom surface of the material-bearing machine. When the grabber 4 is closed, the pressure of the boom cylinder 21 is adjusted to P, where P = P1 - P0, that is, the pressure required to support the grabber 1 in this posture minus the support force P0 of the bottom surface of the material-bearing machine on the grabber 4. This ensures that the grabber 4 and the bottom surface of the material-bearing machine maintain a constant and small force, avoiding excessive force between the grabber 4 and the bottom surface of the material-bearing machine, which could cause collision damage, improves the safety of the operation, and also solves the problem of the grabber 4 not grabbing the material cleanly, thus improving the loading and unloading efficiency.

[0021] This invention also provides a system based on the boom floating control method of the material handling machine 1, such as... Figure 2 The system mainly includes a control valve 5, a float switch 6, and an electronic controller 7. The control valve 5 is used to change the working posture of the boom 2, stick 3, and grab bucket 4 for loading and unloading bulk materials. The float switch 6 is used to enable the boom and grab bucket 4 to work simultaneously. While the grab bucket 4 is closing to grab the bulk materials, it drives the boom 2 to lift, reducing the pressure on the bottom surface of the material support. The input end of the electronic controller 7 is electrically connected to a first sensor 71 for detecting the tilt angle α of the boom 2 and a second sensor 72 for detecting the tilt angle b of the stick 3. The output end is electrically connected to an electro-proportional relief valve 73 for changing the pressure value of the boom cylinder 21. When the grabber 1 is operating in various postures, it reads the corresponding tilt angle information of the first sensor 71 and the second sensor 72 in real time, and feeds it back to the electronic controller 7 for program logic calculation in combination with the structural parameters of the grabber 1.

[0022] Furthermore, in a specific implementation, the control valve 5 provided in the embodiment of the present invention includes a boom handle valve 51, a stick handle valve 52, a grab handle valve 53, and a multi-way valve 54. The pilot oil sources of the boom handle valve 51, the stick handle valve 52, and the grab handle valve 53 are respectively connected to the corresponding pilot oil ports of the multi-way valve 54. By operating the boom handle valve 51, the main pump oil source acts on the boom cylinder 21 through the working oil port of the multi-way valve 54. By operating the stick handle valve 52, the main pump oil source is connected to the stick cylinder 31 through the working oil port of the multi-way valve 54. By operating the grab handle valve 53, the main pump oil source is connected to the grab cylinder 41 through the working oil port of the multi-way valve 54. Specifically, as shown... Figure 2As shown, by operating the grab handle valve 53, the pilot oil source flows from port b33 of the grab handle valve 53 to port b3 of the multi-way valve 54 and port d3 of the solenoid valve 61 respectively. At this time, the float switch 6 is pressed to energize the solenoid valve 61 and reverse it. The pilot oil source flows from port d1 of the solenoid valve 61 through ports c3 and c2 of the shuttle valve into port b1 of the multi-way valve 54. At this time, the first and third valve cores of the multi-way valve 54 reverse simultaneously, and the main pump oil source can flow into the large chamber of the boom cylinder 21 through port B1 of the multi-way valve 54. At the same time, the main pump oil source flows into the large chamber of the grab cylinder 41 through port B3. The oil in the small chamber of the boom cylinder 21 and the small chamber of the grab cylinder 41 flows back to the oil tank through ports A1 and A3 of the multi-way valve 54 respectively. At this time, the grab 4 closes to grab the material, and the boom 2 is automatically raised.

[0023] Furthermore, in a specific implementation, the floating switch 6 provided in the embodiment of the present invention is connected to a solenoid valve 61. The solenoid valve 61 can control the simultaneous conduction of the main pump oil source of the boom cylinder 21 and the grab bucket cylinder 4. Specifically, as shown in the figure... Figure 2 As shown, the electronic controller 7 performs corresponding program logic operations to calculate the pressure value P1 required to support the large chamber of the boom cylinder 21 of the entire working device under the current posture. Then, the electronic controller 7 issues a command to adjust the electro-proportional relief valve 73 to change the pressure value P of the large chamber of the boom cylinder 21.

[0024] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for controlling the floating motion of a grabbing boom, wherein the grabbing machine (1) includes a boom (2) and a stick (3) hinged together, the boom (2) being hinged to an existing fixed end face, and a boom cylinder (21) for controlling the pitch angle of the boom (2) is also connected to the boom (2), and a grabbing bucket (4) is hinged to the stick (3), characterized in that, include: Step 1: Measure the structural parameters of the material handling machine (1); Step 2: Obtain the tilt angle α of the boom (2) and the tilt angle b of the stick (3) in real time; Step 3: Calculate the pressure P1 required to support the posture of the grabber (1) based on the structural parameters, the tilt angle a of the boom (2) and the tilt angle b of the stick (3); Step 4: Set the constant pressure on the bottom surface of the material support to P0, close the grab bucket (4), and at the same time adjust the pressure of the boom cylinder (21) to P, where P = P1 - P0; The hinge point between the boom (2) and the fixed end face is A, the hinge point between the boom (2) and the stick (3) is B, the hinge point between the stick (3) and the grab bucket (4) is C, the hinge point between the boom cylinder (21) and the fixed end face is D, and the hinge point between the boom cylinder (21) and the boom (2) is E. The structural parameters include the large cavity area S of the boom cylinder (21), the weight G1 of the boom (2), and the weight of the stick (3). G2, weight of the grab (4); G3, length of the line connecting hinge point A and B L11, length of the line connecting hinge point A and the center of mass of the boom (2) L1` and the angle between the line connecting hinge point A and B is a`, length of the line connecting hinge point A and E L6, length of the line connecting hinge point A and D L5 and the angle between the line connecting hinge point A and D and the horizontal plane c, length of the line connecting hinge point B and C L22 and length of the line connecting hinge point B and the center of mass of the boom (3) L2` and the angle between the line connecting hinge point B and C is b`; The expression for the pressure P1 required to support the posture of the gripper (1) is: 。 2. A system based on the floating control method for the material handling boom according to claim 1, characterized in that, Includes control valve (5), float switch (6) and electronic controller (7); The control valve (5) is used to change the working posture of the boom (2), stick (3) and grab (4); The floating switch (6) is used to enable the boom (2) and the grab bucket (4) to work simultaneously; The input terminal of the electronic controller (7) is electrically connected to a first sensor (71) for detecting the tilt angle a of the boom (2) and a second sensor (72) for detecting the tilt angle b of the stick (3), and the output terminal is electrically connected to an electro-proportional relief valve (73) for changing the pressure value of the boom cylinder (21).

3. The floating control system for a material handling boom as described in claim 2, characterized in that, The control valve (5) includes a boom handle valve (51), a stick handle valve (52), a grab handle valve (53), and a multi-way valve (54). The pilot oil sources of the boom handle valve (51), the stick handle valve (52), and the grab handle valve (53) are respectively connected to the corresponding pilot oil ports of the multi-way valve (54). By operating the boom handle valve (51), the main pump oil source acts on the boom cylinder (21) through the working oil port of the multi-way valve (54). By operating the stick handle valve (52), the main pump oil source is connected to the stick cylinder (31) through the working oil port of the multi-way valve (54). By operating the grab handle valve (53), the main pump oil source is connected to the grab cylinder (41) through the working oil port of the multi-way valve (54).

4. The floating control system for a material handling boom as described in claim 3, characterized in that, The floating switch (6) is connected to a solenoid valve (61), which can control the main pump oil source of the boom cylinder (21) and the grab bucket (4) cylinder to be turned on simultaneously.

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