Coal mine support with main supporting rod structure and design method

Abstract

The invention provides a main supporting rod structure coal mine support and a design method, a main supporting rod comprises an upper supporting rod and a lower supporting rod, an electric boosting cylinder is additionally arranged between a base and the main supporting rod, and when the electric boosting cylinder provides small boosting force, the upper supporting rod provides large initial supporting force. Concave-convex surface contact is added to hinge parts among the upper supporting rod, the lower supporting rod, the top plate and the base, and the structural strength is improved. The design method comprises the steps of selecting support parameters to calculate the length of an upper supporting rod, the length of a lower supporting rod, the maximum length of an electric boosting cylinder, the minimum length of the electric boosting cylinder and boosting force needing to be provided by the electric boosting cylinder, and combining an established structure and force control correlation function of the coal mine support with the length control of the electric boosting cylinder as a target. And PID closed-loop control is carried out. The stability of the coal mine support is improved, the consistency and stability of the technical performance, quality and structure of the electric boosting cylinder of the coal mine support with the main supporting rod structure are guaranteed, and the control precision and control stability of the electric cylinder are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of coal mine supports, and specifically to a coal mine support with a main support rod structure and a design method thereof. Background Art

[0002] Coal mine supports are the main mechanical equipment used for roof support in underground mining work. The reliability and stability of coal mine supports are directly related to the safety of the entire coal mining face and are one of the most important equipment in the underground coal mining face. The existing coal mine supports widely adopt the form of hydraulic supports. However, the leakage of hydraulic oil deteriorates the working environment and pollutes groundwater, bringing serious safety hazards and work inconveniences to underground operators.

[0003] Hydraulic supports rely on hydraulic oil as the medium for transmitting power. The hydraulic oil is pressurized by a hydraulic pump and then transported to the corresponding hydraulic circuits to drive the movement of components such as pistons inside the electric cylinders, thereby driving the load to act. The main leakage parts of the hydraulic oil in hydraulic supports are concentrated in the support columns. When removing and inspecting the columns with liquid leakage, the main reason for the leakage is problems caused by seal failures, and the existing technology cannot solve the leakage problem caused by the seal failure of hydraulic supports. Secondly, there are processes such as the flow of hydraulic oil and the movement of components in the hydraulic system, and the overall response speed is relatively slow, and the control accuracy is not high enough.

[0004] Electrifying coal mine supports can fundamentally solve the leakage problem. If the hydraulic drive columns are simply replaced with electric drive columns, the problem of insufficient initial support force will occur. Therefore, there is an urgent need to design a coal mine support with a main support rod structure, change the main support structure and add an electric boosting cylinder to solve the problems of insufficient initial support force and inaccurate control of electric supports. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a coal mine support with a main support rod structure and a design method thereof to solve the problems of insufficient initial support force and inaccurate control of existing electric supports.

[0006] To solve the above technical problems, the embodiments of the present invention provide the following technical solutions: A coal mine support with a main support rod structure includes a main support rod, an electric boosting cylinder, a roof, a base, a shield beam and a connecting rod.

[0007] The main support rod structure includes an upper support rod and a lower support rod. The lower end of the upper support rod is hinged to the upper end of the lower support rod, and the convex surface at the lower end of the upper support rod is matched with the concave surface at the upper end of the lower support rod.

[0008] The roof is hinged to the upper end of the upper support rod, and a concave surface is provided at the connection part between the roof and the upper support rod to be matched with the convex surface at the upper end of the upper support rod.

[0009] The base is hinged to the lower end of the lower support rod, and a concave surface is provided at the connection part between the base and the lower support rod to cooperate with the convex surface at the lower end of the lower support rod;

[0010] The upper end of the shield beam is hinged to the tail of the roof, the lower end of the shield beam is hinged to the upper ends of four connecting rods, and the lower ends of the four connecting rods are hinged to the tail of the base;

[0011] The upper end of the electric boosting cylinder is hinged at the connection part between the upper support rod and the lower support rod, and the lower end of the electric boosting cylinder is hinged to the base;

[0012] The input end of the electric boosting cylinder is connected to a servo motor, the input end of the servo motor is connected to a servo driver, the input end of the servo driver is connected to a D / A conversion module, the input end of the D / A conversion module is connected to a PID controller, the input end of the PID controller is connected to an industrial computer, the output end of the servo motor is also connected to an encoder, the output end of the encoder is connected to a motion control card, and the output end of the motion control card is connected to the PID input end.

[0013] Further, when the main support structure of the coal mine support is in a non-operating state, the upper end of the electric boosting cylinder retracts into the cylinder, the angle between the upper support rod and the lower support rod is small, and the distance between the roof and the base is small. When the main support structure of the coal mine support is operating, the upper end of the electric boosting cylinder extends outwards, driving the lower end of the upper support rod and the upper end of the lower support rod to move, increasing the angle between the upper support rod and the lower support rod, and driving the roof to rise.

[0014] Further, when the roof contacts the coal seam during the rising process, at this time, the angle between the upper support rod and the lower support rod is large, and the angle between the electric boosting cylinder and the lower support rod can use a smaller force within a specific range to continue to push the lower end of the upper support rod and the upper end of the lower support rod to move, so that the roof continues to rise, providing a larger initial support force. When the angle between the upper support rod and the lower support rod reaches the maximum, the rising height of the roof reaches the maximum.

[0015] The present invention also proposes a design method for a coal mine support with the above-mentioned main support rod structure, which includes the following steps:

[0016] S1. According to the maximum rising height H of the coal mine support and the required initial support force F, select the manufacturing parameters of the main support rod structure. The manufacturing parameters include the number N of the main support rod structures, the angle α between the lower support rod and the base when the maximum angle between the upper support rod and the lower support rod is 180 degrees, the angle β between the lower support rod and the base when the minimum angle between the upper support rod and the lower support rod, the ratio of the upper support rod to the lower support rod The horizontal distance x and the vertical distance y between the hinge point of the lower support rod and the base and the hinge point of the electric boosting cylinder and the base, the diameter φ of the hinge cylindrical pin of the main support rod structure, and the area S of the hinge surface;

[0017] S2. Lift the roof of the support to the highest position. At this time, the angle between the upper support rod and the lower support rod is 180 degrees, and the maximum length L of the electric boosting cylinder is obtained Zmax ;

[0018] S3. Lower the support roof to the lowest position and obtain the minimum length L of the electric force - increasing cylinder. Zmin ;

[0019] S4. Adjust the support roof to the position where a larger initial support force needs to be provided and obtain the additional force F that the electric force - increasing cylinder needs to provide. Z ;

[0020] S5. Establish the correlation function of the additional force F that the electric force - increasing cylinder needs to provide, Z the angle γ between the lower strut and the base, 2 the angle γ between the upper strut and the roof, 1 and the correlation function of the angle α and β between the lower strut and the base corresponding to the maximum length L and the minimum length L of the electric force - increasing cylinder respectively. Zmax the minimum length L of the electric force - increasing cylinder Zmin ;

[0021] S6. According to the additional force F that the electric force - increasing cylinder needs to provide measured in real - time, Z take the extended length L of the corresponding electric force - increasing cylinder as the PID control quantity. After the solution of the PID controller algorithm, output a voltage signal to the servo driver through the D / A conversion module, and the servo driver controls the rotation of the servo motor to control the expansion and contraction of the electric cylinder with the PID algorithm.

[0022] Further, after adjusting the support roof to the position where it is subjected to the maximum working resistance in step S2, verify whether the diameter φ of the articulated cylindrical pin and the area S of the articulated surface meet the structural strength through simulation.

[0023] Further, according to S2, obtain the length L of the upper strut 上 and the length L of the lower strut 下 by the following calculation method:

[0024]

[0025] Further, the correlation function of the angle α between the lower strut and the base corresponding to the maximum length L of the electric force - increasing cylinder Zmax is:

[0026]

[0027] Further, the correlation function of the angle β between the lower strut and the base corresponding to the minimum length L of the electric force - increasing cylinder Zmin is:

[0028]

[0029] Further, the additional force F that the electric force - increasing cylinder needs to provide, Z the angle γ between the lower strut and the base2 1. The angle γ between the upper support rod and the top plate 1 The correlation function is specifically as follows:

[0030] where γ 2 is the angle between the lower support rod and the base at this time, and γ 1 is the angle between the upper support rod and the top plate at this time.

[0031] Furthermore, the step S6 further includes designing the overload detection of the electric boosting cylinder. When the PID controller detects the fault information of overvoltage and overload during the control process, the servo driver issues an alarm and controls the servo motor brake to protect the electric boosting cylinder from failure.

[0032] The beneficial effects of the above technical solutions of the present invention are as follows:

[0033] 1. The present invention adds an electric boosting cylinder between the base and the main support rod structure, and the electric boosting cylinder can provide a small boosting force to enable the main support rod to provide a large initial support force.

[0034] 2. The present invention increases the contact between the convex surface and the concave surface at the hinged connection parts between the upper support rod and the top plate, between the upper support rod and the lower support rod, and between the lower support rod and the base, which increases the structural strength and improves the stability of the coal mine support.

[0035] 3. The present invention is a complete, unified and standardized design method for the electric boosting cylinder technology and structural parameters of the coal mine support with the main support rod structure. Through the present invention, the consistency and stability of the technical performance, quality and structure of the electric boosting cylinder of the coal mine support with the main support rod structure can be ensured.

[0036] 4. The present invention designs the PID motion control method for the electric boosting cylinder. Combining with the established correlation function of the structure and force control of the coal mine support, taking the length control of the electric boosting cylinder as the target, PID closed-loop control is carried out, which improves the control accuracy and control stability of the electric cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the coal mine support with the main support rod structure of the present invention;

[0038] Figure 2 It is a flow chart of the design method of the coal mine support with the main support rod structure of the present invention;

[0039] Figure 3 It is a schematic diagram of the maximum height of the coal mine support with the main support rod structure of the present invention;

[0040] Figure 4 It is a schematic diagram of the minimum height of the coal mine support with the main support rod structure of the present invention;

[0041] Figure 5Schematic diagram of the position for providing the initial support force for the main support structure of the coal mine support of the present invention;

[0042] Figure 6 Schematic diagram of the initial support force and force increase for the main support rod structure of the coal mine support;

[0043] Figure 7 PID control principle block diagram of the electric force increasing cylinder of the present invention.

[0044] In the figure: 1 roof; 2 upper support rod; 3 lower support rod; 4 base; 5 electric force increasing cylinder; 6 connecting rod; 7 shield. Detailed implementation manners

[0045] To make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the accompanying drawings and specific embodiments.

[0046] As Figure 1 shown, the present invention discloses a main support rod structure of a coal mine support, including a main support rod, an electric force increasing cylinder 5, a roof 1, a base 4, a shield beam 7 and a connecting rod 6.

[0047] As Figure 1 shown, the main support rod structure includes an upper support rod 2 and a lower support rod 3. The lower end of the upper support rod 2 is hinged to the upper end of the lower support rod 3, and the convex surface at the lower end of the upper support rod 2 cooperates with the concave surface at the upper end of the lower support rod 3; the roof 1 is hinged to the upper end of the upper support rod 2, and a concave surface is provided at the connection part between the roof 1 and the upper support rod 2 to cooperate with the convex surface at the upper end of the upper support rod 2; the base 4 is hinged to the lower end of the lower support rod 3, and a concave surface is provided at the connection part between the base 4 and the lower support rod 3 to cooperate with the convex surface at the lower end of the lower support rod 3. In the present invention, the contact of the convex surface and the concave surface is added at the hinged connection parts between the upper support rod 2 and the roof 1, the upper support rod 2 and the lower support rod 3, and the lower support rod 3 and the base 4, increasing the structural strength and improving the stability of the coal mine support.

[0048] As Figure 1 shown, the upper end of the shield beam 7 is hinged to the tail of the roof 1, the lower end of the shield beam 7 is hinged to the upper ends of four connecting rods 6, and the lower ends of the four connecting rods 6 are hinged to the tail of the base 4; the upper end of the electric force increasing cylinder 5 is hinged at the connection part between the upper support rod 2 and the lower support rod 3, and the lower end of the electric force increasing cylinder 5 is hinged to the base 4.

[0049] Among them, in the non-operating state of the main support structure of the coal mine support, the upper end of the electric force increasing cylinder 5 retracts into the cylinder, the included angle between the upper support rod 2 and the lower support rod 3 is small, and the distance between the roof 1 and the base 4 is small. When the main support structure of the coal mine support operates, the upper end of the electric force increasing cylinder 5 extends outwards, driving the lower end of the upper support rod 2 and the upper end of the lower support rod 3 to move, increasing the included angle between the upper support rod 2 and the lower support rod 3, and driving the roof 1 to rise.

[0050] Among them, when the roof plate 1 contacts the coal seam during the ascending process, the angle between the upper support rod 2 and the lower support rod 3 is relatively large at this time. The angle between the electric boosting cylinder 5 and the lower support rod 3 can use a smaller force within a specific range to continue pushing the lower end of the upper support rod 2 and the upper end of the lower support rod 3 to move, so that the roof plate 1 continues to rise and provides a larger initial support force. When the angle between the upper support rod 2 and the lower support rod 3 reaches the maximum of 180 degrees, the rising height of the roof plate 1 reaches the maximum. In the present invention, an electric boosting cylinder 5 is added between the base 4 and the main support rod structure, and a smaller boosting force can be provided by the electric boosting cylinder 5 to enable the main support rod to provide a larger initial support force.

[0051] As Figure 7 shown, the input end of the electric boosting cylinder is connected to the servo motor, the input end of the servo motor is connected to the servo driver, the input end of the servo driver is connected to the D / A conversion module, the input end of the D / A conversion module is connected to the PID controller, the input end of the PID controller is connected to the industrial control computer, the output end of the servo motor is also connected to the encoder, the output end of the encoder is connected to the motion control card, and the output end of the motion control card is connected to the PID input end. The industrial control computer issues instructions to the control system according to its own requirements. The motion control card reads the feedback value of the encoder through the motion control card, thereby forming a closed-loop control to ensure the accurate control of the input quantity. The D / A conversion module converts the length control signal into a voltage signal and outputs it to the servo driver. The servo driver, as the core component of the control system, drives the motor to rotate. On the other hand, it plays a role in fault detection for the control system. When fault information such as overvoltage and overload is found, the servo driver will issue an alarm, and at the same time, the servo motor will hold the brake to achieve fault protection. The servo motor provides the power required for the system to work. The electric boosting cylinder is equipped with a ball screw mechanism inside, which converts the rotational motion into a linear motion, drives the piston to expand and contract, and realizes the reciprocating motion of the electric cylinder.

[0052] During specific implementation, the target length signal required to control the electric boosting cylinder can be converted into a speed signal controlled within time t. The speed signal is calculated through the PID controller algorithm, and a voltage signal is output to the servo driver by the D / A conversion module. The servo driver controls the motor to rotate to control the expansion and contraction of the electric cylinder with the PID algorithm. The feedback device consists of a motor encoder (incremental type) and a motion control card, which collects the speed signal of the motor in real time and transmits it to the input end to achieve closed-loop control.

[0053] Meanwhile, the present invention also provides a parameter design method for the main support rod and the electric boosting cylinder. According to the maximum height of the coal mine support and the initial support force required by the upper support rod, the parameter and control design of the main support rod and the electric boosting cylinder can be quickly completed. The method flow chart is as Figure 2 shown.

[0054] This design method includes the following steps:

[0055] Step 1: According to the maximum ascending height H of 2.62 m and the required initial support force F of 5000 kN for the coal mine support, select the manufacturing parameters of the main support rod structure. The manufacturing parameters include the number N of the main support rod structures being 2. When the maximum angle between the upper support rod and the lower support rod is 180 degrees, the angle α between the lower support rod and the base is 82°. When the minimum angle between the upper support rod and the lower support rod, the angle β between the lower support rod and the base is 55°. The ratio of the upper support rod to the lower support rod is 1.65. The horizontal distance x between the hinge point of the lower support rod and the base and the hinge point of the electric force amplifier cylinder and the base is 1.5 m, and the vertical distance y is 0.55 m. The diameter φ of the hinge cylindrical pin of the main support rod structure is 0.1 m, and the hinge surface area S is 0.0655 m 2 .

[0056] Step 2: Lift the support roof to the highest position as shown in Figure 3 . At this time, the angle between the upper support rod and the lower support rod is 180 degrees. According to the maximum height H = 2.62 m, the length L of the upper support rod in Figure 3 , the length L of the lower support rod 上 , and the maximum length L of the electric force amplifier cylinder 下 are calculated as follows: zmax

[0057]

[0058] Step 3: Lower the support roof to the lowest position as shown in Figure 4 . The minimum length L of the electric force amplifier cylinder Zmin is calculated as follows:

[0059]

[0060] Step 4: Adjust the support roof to the position where a relatively large initial support force needs to be provided as shown in Figure 5 . The initial support force F provided by the upper support rod, the additional force F provided by the electric force amplifier cylinder Z and the schematic diagram of the supporting force provided by the lower support rod are as shown in Figure 6 . At this time, the angle γ between the upper support rod and the roof 1 is 95.46°, the angle γ between the lower support rod and the base 2 is 77.69°. The additional force F that the electric force amplifier cylinder needs to provide Z is calculated as follows:

[0061]

[0062] Through the above method, establish the correlation functions of the additional force F that the electric force amplifier cylinder needs to provide Z , the angle γ between the lower support rod and the base 2 , the angle γ between the upper support rod and the roof 1 , and the maximum length L of the electric force amplifier cylinder Zmax ​, the minimum length L of the electric booster cylinder Zmin The correlation functions of the included angles α and β between the lower support rod and the base respectively corresponding thereto.

[0063] Then, according to the boosting force F required by the electric booster cylinder measured in real time Z , the extended length L of the corresponding electric booster cylinder (controlled by the speed movement within t time) is used as the PID control quantity. After the solution of the PID controller algorithm, the D / A conversion module outputs a voltage signal to the servo driver, and the servo driver controls the rotation of the servo motor to control the telescoping of the electric cylinder with the PID algorithm.

[0064] In addition, adjust the position of the support top plate to be subjected to the maximum working resistance of 5500 kN. Through simulation, when the diameter φ of the articulated cylindrical pin is 0.1 m and the articulated surface area S is 0.0655 m 2 , when the main support rod structure material is 60 kg grade high-strength steel, the stress at the maximum stress point of the articulated part is 299 MPa, which meets the allowable stress requirements in the standard GB25974.1-2010, and the designed main support rod structure bracket meets the strength requirements.

[0065] The above is the preferred implementation manner of the present invention. It should be noted that for those of ordinary skill in the art of the present technology, without departing from the principle described in the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A main support rod structure coal mine support, comprising a main support rod, an electric booster cylinder (5), a top plate (1), a base (4), a shield beam (7) and a connecting rod (6), characterized in that: The main support rod structure comprises an upper support rod (2) and a lower support rod (3), the lower end of the upper support rod (2) is hinged to the upper end of the lower support rod (3), and the convex surface of the lower end of the upper support rod (2) matches the concave surface of the upper end of the lower support rod (3); The top plate (1) is hinged to the upper end of the upper support rod (2), and a concave surface is provided at the connection portion between the top plate (1) and the upper support rod (2) to match the convex surface at the upper end of the upper support rod (2); The base (4) is hinged to the lower end of the lower support rod (3), and a concave surface is provided at the connection portion between the base (4) and the lower support rod (3) to match the convex surface at the lower end of the lower support rod (3); The upper end of the shielding beam (7) is hinged to the rear end of the top plate (1), the lower end of the shielding beam (7) is hinged to the upper ends of the four connecting rods (6), and the lower ends of the four connecting rods (6) are hinged to the rear end of the base (4); The upper end of the electric booster cylinder (5) is hinged to the connection between the upper support rod (2) and the lower support rod (3), and the lower end of the electric booster cylinder (5) is hinged to the base (4); The input end of the electric booster cylinder (5) is connected to a servo motor, the input end of the servo motor is connected to a servo driver, the input end of the servo driver is connected to a D / A conversion module, the input end of the D / A conversion module is connected to a PID controller, the input end of the PID controller is connected to an industrial computer, the output end of the servo motor is also connected to an encoder, the output end of the encoder is connected to a motion control card, and the output end of the motion control card is connected to the PID input end.

2. A main support rod structure coal mine support according to claim 1, characterized in that: When the main support structure of the coal mine support is in a non-operating state, the upper end of the electric booster cylinder (5) is retracted into the cylinder, the angle between the upper support rod (2) and the lower support rod (3) is small, and the distance between the top plate (1) and the base (4) is small. When the main support structure of the coal mine support is in operation, the upper end of the electric booster cylinder (5) extends outward, driving the lower end of the upper support rod (2) and the upper end of the lower support rod (3) to move, thereby increasing the angle between the upper support rod (2) and the lower support rod (3), and driving the top plate (1) to rise.

3. A main support rod structure coal mine support according to claim 1, characterized in that: When the roof (1) contacts the coal seam during the rising process, the angle between the upper support rod (2) and the lower support rod (3) is relatively large. The angle between the electric booster cylinder (5) and the lower support rod (3) can be within a specific range, and a relatively small force can be used to continue to push the lower end of the upper support rod (2) and the upper end of the lower support rod (3) to move, so that the roof (1) continues to rise, providing a relatively large initial support force. When the angle between the upper support rod (2) and the lower support rod (3) reaches a maximum of 180 degrees, the rising height of the roof (1) reaches a maximum.

4. A method for designing a main support rod structure coal mine support according to claim 1 comprises the following steps: S1. According to the maximum height H of the coal mine support and the required initial support force F, the main support rod structure is selected to set the manufacturing parameters, which include the number N of the main support rod structure, the angle α between the lower support rod and the base when the maximum angle between the upper support rod and the lower support rod is 180 degrees, the angle β between the lower support rod and the base when the upper support rod and the lower support rod are at their minimum angle, and the ratio of the upper support rod to the lower support rod. The horizontal distance x and vertical distance y between the hinge point between the lower support rod and the base and between the electric booster cylinder and the base, the diameter φ of the hinged cylindrical pin of the main support rod structure, and the hinged surface area S; S2. Lift the top plate of the bracket to the highest position. At this time, the angle between the upper support rod and the lower support rod is 180 degrees. Calculate the maximum length L of the electric booster cylinder. Zmax ; S3. Lower the bracket top plate to the lowest position and find the minimum length L of the electric booster cylinder. Zmin ; S4. Adjust the top plate of the bracket to the position where a larger initial support force is required, and calculate the force F required by the electric booster cylinder. Z ; S5. Establish the force booster F required by the electric booster cylinder Z , the correlation function of the angle between the lower support rod and the base γ2, the angle between the upper support rod and the top plate γ1, and the maximum length L of the electric booster cylinder Zmax , Minimum length of electric booster cylinder L Zmin Correlation functions of the angles α and β between the lower support rod and the base, respectively; S6, according to the real-time measurement of the electric booster cylinder required to provide the boost F Z The extension length L of the corresponding electric booster cylinder is used as the PID control quantity. After being solved by the PID controller algorithm, the D / A conversion module outputs a voltage signal to the servo driver. The servo driver controls the rotation of the servo motor and controls the extension and retraction of the electric cylinder with the PID algorithm.

5. The main support rod structure coal mine support design method according to claim 4 is characterized in that: In step S2, after adjusting the bracket top plate to the position subject to the maximum working resistance, simulation is performed to verify whether the hinge cylindrical pin diameter φ and the hinge surface area S meet the structural strength requirements.

6. A method for designing a main support rod structure coal mine support as claimed in claim 4, characterized in that: According to S2, the upper support rod length L is obtained by the following calculation method: 上 The length of the lower support rod L 下 :

7. A method for designing a main support rod structure coal mine support as claimed in claim 4, characterized in that: The maximum length L of the electric booster cylinder Zmax The corresponding correlation function of the angle α between the lower support rod and the base is:

8. A method for designing a main support rod structure coal mine support as claimed in claim 4, characterized in that: The minimum length L of the electric booster cylinder Zmin The corresponding correlation function of the angle β between the lower support rod and the base is:

9. A method for designing a main support rod structure coal mine support as claimed in claim 4, characterized in that: The electric booster cylinder needs to provide the boost F Z , the correlation function of the angle between the lower support rod and the base γ2, and the angle between the upper support rod and the top plate γ1 is as follows: Among them, γ2 is the angle between the lower support rod and the base at this time, and γ1 is the angle between the upper support rod and the top plate at this time.

10. A method for designing a main support rod structure coal mine support as claimed in claim 4, characterized in that: The step S6 also includes designing an overload detection for the electric booster cylinder. When the PID controller detects that there is overvoltage or overload fault information in the control process, the servo driver will issue an alarm and control the servo motor to brake, thereby protecting the electric booster cylinder from faults.

Images