System for realizing load-varying braking of mine hoist

Abstract

The utility model relates to a system for realizing load-varying braking of a mine hoist, which comprises a sensor unit, a control unit and a hydraulic valve group, and is characterized in that the sensor unit is used for detecting the rotating speed of the hoist, the current and voltage of a main motor of the hoist and the oil pressure of the hydraulic valve group and transmitting detected signals to the control unit; the control unit is used for receiving a signal of the sensor unit, generating an oil pressure control signal according to the received signal and transmitting the oil pressure control signal to the hydraulic valve group; and the hydraulic valve group is connected with the control unit, the elevator hydraulic station and the elevator brake, and controls the oil pressure value of the elevator brake during braking in real time according to an oil pressure control signal sent by the control unit. The system is independent of the hydraulic station and can supplement the function that the braking torque of the hydraulic station changes along with the load of the hoist, so that the system for braking the mine hoist by changing the load can be applied to a new hydraulic station and can also be applied to the technical transformation of an old hydraulic station.

Description

Technical Field

[0001] The utility model relates to the technical field of mine hoist control, in particular to a system for realizing load-dependent braking of a mine hoist. Background Art

[0002] In the previous hoisting system, when the mine hoist implements safety braking when a major fault occurs, the deceleration process from the immediate speed to the stationary speed is realized by applying emergency braking to the hoist with the brake. The hydraulic station brake oil pressure of the hydraulic brake system is usually constant, that is, a constant torque hydraulic brake system. Since the braking torque of this braking system is a constant value, and the hoisting load, hoisting speed and hoisting distance of the hoist are variable relative to different hoisting processes, especially the single rope hoist, the total load of the hoist changes with the real-time change of the hoisting load and the length of the hoisting wire rope during its operation, resulting in different braking effects. Compared with the high-speed heavy load lowering working condition, the deceleration will be too small and the overwinding and top collision accident will occur; compared with the high-speed heavy load lifting working condition, it is very likely that the braking force will be too large and too fierce, resulting in a rope breaking accident, which will bring economic losses to the mine production and even serious consequences of casualties!

[0003] Some people have tried to set up a variable torque hydraulic station according to the lifting direction, that is, to set two different safety brake oil pressure values ​​according to the lifting direction. However, this oil pressure value control method completely ignores the basic mechanical principle that the lifting direction does not represent the direction of the load force. In this sense, its control effect sometimes backfires and has the opposite result, and becomes a safety hazard!

[0004] Some people also use constant deceleration hydraulic stations on large hoists. Theoretically, the safety brake oil pressure and braking torque can change to adapt to the changing conditions of the hoist load, but the control method is speed-oil pressure dual closed-loop control. Both speed control and oil pressure control are large time constant systems, and the system has poor rapidity and followability, resulting in step-type or even step-change changes in safety braking speed and deceleration, which will also cause impact on the hoist and wire rope and is costly.

[0005] It can be seen that the above-mentioned existing mine hoist hydraulic braking systems obviously have defects. In order to solve the above-mentioned problems, it is urgently necessary to involve a device that can make the braking torque of the hydraulic braking system change with the load of the hoist. The load refers to the static load (that is, the static tension difference of this lifting) and the dynamic load (that is, the change in rotational inertia caused by changes in the working state of lifting or lowering the heavy object, the load size, the speed, the length of the wire rope corresponding to the stroke position, etc.). The device can control the braking force according to the load size and thereby achieve a basically unchanged safety braking deceleration. Summary of the invention

[0006] To solve the above problems, the utility model proposes a system for realizing load-dependent braking of a mine hoist, which is independent of the hydraulic station and can supplement the function of the hydraulic station's braking torque changing with the load of the hoist, thereby meeting the demand for load-dependent braking of the mine hoist.

[0007] The purpose of the utility model and the technical problem to be solved are achieved by adopting the following technical solutions. According to the utility model, a system for realizing load-dependent braking of a mine hoist is proposed, which includes a sensor unit, a control unit and a hydraulic valve group, wherein the sensor unit is used to detect the rotation speed of the hoist, the current and voltage of the hoist main motor and the oil pressure of the hydraulic valve group, and transmits the detected signal to the control unit; the control unit is used to receive the signal of the sensor unit and generate an oil pressure control signal according to the received signal and transmit it to the hydraulic valve group; the hydraulic valve group is connected to the control unit, the hoist hydraulic station and the hoist brake, and controls the oil pressure value of the hoist brake in real time according to the oil pressure control signal sent by the control unit.

[0008] The purpose of the utility model and the solution to its technical problems can also be further achieved by adopting the following technical measures.

[0009] The above-mentioned system for realizing load-dependent braking of a mine hoist, the hydraulic valve group includes an energy storage part and a control part, wherein the energy storage part includes a pressure gauge, a one-way valve and an accumulator connected in sequence through a pipeline along the flow direction of the oil, and the oil pressure sensor of the sensor unit for detecting the oil pressure of the hydraulic valve group is located between the pressure gauge and the one-way valve; the output end of the energy storage part is connected to the control part, and the input end is connected to the pipeline that transports oil to the hoist brake from the hoist hydraulic station through a hydraulic pipeline, so that when the hoist is opened in the normal working state, the hoist brake is Part of the oil output by the hoist hydraulic station is delivered to the hoist brake, and the other part is delivered to the accumulator to fill the accumulator with oil. When the hoist is braked under normal working conditions, the accumulator maintains a high oil pressure storage state; when the hoist is safely braked, the oil circuit connected to the hoist brake in the hoist hydraulic station is cut off, so that the oil in the hoist brake is returned to the hoist hydraulic station return tank through the hydraulic valve group; the control part is used to realize the opening and closing of the hydraulic valve group to the hoist hydraulic station return oil channel and the oil pressure of the hydraulic valve group when returning oil to the hoist hydraulic station.

[0010] The aforementioned system for realizing load-dependent braking of a mine hoist, the control part of which includes a solenoid valve and a proportional valve, wherein the T port of the solenoid valve is connected to the inlet of the proportional valve, and the outlet of the proportional valve is connected to the oil return tank of the hoist hydraulic station; the B port of the solenoid valve is simultaneously connected to the outlet of the accumulator and the one-way valve, and the A port is connected to the oil pressure sensor; and when the solenoid valve is energized, its A, B, P, and T ports are not connected to each other and the oil circuit is cut off, and when the solenoid valve is de-energized, both the A port and the B port are connected to the T port.

[0011] The aforementioned system for implementing load-dependent braking of a mine hoist, the sensor unit also includes a speed sensor installed on the hoist and connected to the hoist main shaft, and a current transformer and a voltage transformer installed next to the hoist main motor and connected to the main circuit of the hoist main motor.

[0012] The above-mentioned system for implementing load-dependent braking of a mine hoist comprises a control unit including a PLC controller for receiving signals from a sensor unit and sending oil pressure control signals to a hydraulic valve group, and a touch screen capable of human-computer dialogue with the PLC controller.

[0013] In the aforementioned system for implementing load-dependent braking of a mine hoist, the oil pressure control signal includes an analog control signal for controlling a proportional relief valve and a digital control signal for controlling a solenoid valve.

[0014] In the aforementioned system for implementing load-dependent braking of a mine hoist, the control unit and the hydraulic valve group are located in a box next to the hydraulic station.

[0015] Compared with the prior art, the utility model has obvious advantages and beneficial effects. By means of the above technical solution, the utility model can achieve considerable technical progress and practicality, and has wide industrial utilization value, and has at least the following advantages:

[0016] The utility model realizes the load-dependent braking system of the mine hoist, which is independent of the hydraulic station and can supplement the function of the hydraulic station's braking torque changing with the load of the hoist, so that the utility model realizes the load-dependent braking system of the mine hoist can be applied to the matching of new hydraulic stations and can also be applied to the technical transformation of old hydraulic stations. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the composition of a system for realizing load-dependent braking of a mine hoist according to the utility model;

[0018] Figure 2 The utility model is a schematic diagram of the oil circuit of a hydraulic valve group of a system for realizing load-dependent braking of a mine hoist.

[0019]

Main component symbol description

[0020] 1- Hoist

[0021] 1.1-Lifting machine brake

[0022] 2- Hoist main motor

[0023] 3-Lifting hydraulic station

[0024] 4-Sensor unit

[0025] 5-Control Unit

[0026] 6-Hydraulic valve group

[0027] 7-Hydraulic pipeline

[0028] 4.1-Speed ​​sensor

[0029] 4.2- Current transformer

[0030] 4.3- Voltage transformer

[0031] 5.1-Touch screen

[0032] 6.1-Proportional relief valve

[0033] 6.2-Solenoid valve

[0034] 6.3-Accumulator

[0035] 6.4- Check valve

[0036] 6.5-Oil pressure sensor

[0037] 6.6-Oil pressure gauge

[0038] 7-Hydraulic pipeline

[0039] 8-Oil pipeline

[0040] 9-Oil return pipe DETAILED DESCRIPTION

[0041] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation method, structure, characteristics and effects of the system for realizing load-dependent braking of a mine hoist proposed by the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0042] See also Figure 1 and Figure 2 , which is a schematic diagram of the various parts of the system for realizing load-dependent braking of a mine hoist according to the utility model, and the system includes a sensor unit 4, a control unit 5 and a hydraulic valve group 6. The sensor unit 4 is used to detect the rotation speed of the hoist 1, the current and voltage of the hoist main motor 2 and the oil pressure of the hydraulic valve group 6, and transmit the detected signal to the control unit 5; the control unit 5 can calculate and generate an oil pressure control signal according to the signal of the sensor unit 4 and transmit it to the hydraulic valve group 6, and the hydraulic valve group 6 is connected to the control unit 5, the hoist hydraulic station 3 and the hoist brake 1.1, and controls the oil pressure value of the hoist brake 1.1 during safe braking according to the control signal sent by the control unit 5.

[0043] In the embodiment of the utility model, the sensor unit 4 includes a speed sensor 4.1, a current transformer 4.2, a voltage transformer 4.3 and an oil pressure sensor 6.5, wherein the speed sensor 4.1 is installed on the hoist 1 and connected to the hoist main shaft to detect the hoist speed, the current transformer 4.2 and the voltage transformer 4.3 are installed next to the hoist main motor 2 and connected to the main circuit of the hoist main motor 2 to detect the current and voltage of the hoist main motor 2, and the oil pressure sensor 6.5 is installed on the hydraulic valve group 6 and detects the actual oil pressure value of the hydraulic valve group 6.

[0044] The hydraulic valve group 6 includes an energy storage part and a control part, wherein the energy storage part includes a pressure gauge 6.6, a one-way valve 6.4 and an accumulator 6.3 arranged in sequence on the pipeline along the flow direction of the oil, and the input end of the energy storage part is connected to the oil delivery pipeline 8 for delivering oil from the hoist hydraulic station 3 to the hoist brake 1.1 through a hydraulic pipeline 7, so that when the hoist is working normally, part of the oil output by the hoist hydraulic station 3 is delivered to the hoist brake 1.1, and the other part is delivered to the accumulator 6.3 to charge the accumulator 6.3. The one-way valve 6.4 is used to prevent the oil in the accumulator 6.3 from flowing back to the oil delivery pipeline 8 through the hydraulic pipeline 7. The oil pressure sensor 6.5 is located on the pipeline between the pressure gauge 6.6 and the one-way valve 6.4. The hydraulic valve group is also connected to the hoist hydraulic station 3 through the oil return pipe 9, so that when the hoist is safely braked, the oil in the hoist brake 1.1 is transported to the A port of the solenoid valve 6.2 through the hydraulic pipeline 7 and the sensor 6.5.

[0045] The control part includes a solenoid valve 6.2 and a proportional valve 6.1, wherein the T port of the solenoid valve 6.2 is connected to the inlet of the proportional valve, the outlet of the proportional valve 6.2 is connected to the oil return tank of the hydraulic station 3 of the hoist through the oil return pipe 9, the B port of the solenoid valve 6.2 is connected to the outlet of the accumulator 6.3 and the check valve 6.4 at the same time, and the A port is connected to the sensor 5. In addition, when the solenoid valve 6.2 is powered, its A, B, P, and T ports are not connected to each other and the oil circuit is cut off, and when the power is off, both the A port and the B port are connected to the T port, and the oil delivered to the A port by the hoist 1 or the oil delivered to the B port by the accumulator 6.3 is delivered to the proportional valve 6.1 through the T port.

[0046] The proportional valve 6.1 is an electro-hydraulic proportional control device, and its control signal comes from the analog signal controlled by the oil pressure value in the control unit 5. The size of the control signal determines the oil pressure value flowing through the oil circuit of the proportional relief valve 6.1. The proportional relationship is that the analog control signal 0-10V corresponds to the oil pressure 0-6.3MPa, which is a linear relationship. Under the premise of meeting the required oil pressure, the oil flowing through the proportional valve 6.1 passes through the return oil pipe 9 to the oil tank of the hoist hydraulic station 3.

[0047] The control unit 5 comprises a PLC controller and a touch screen 5.1. Signals from the speed sensor 4.1, the current transformer 4.2, the voltage transformer 4.3 and the oil pressure sensor 6.5 are transmitted to the PLC controller in the control unit 5. The touch screen 5.1 is connected to the PLC controller in the control unit 5 for communication and human-machine dialogue. The oil pressure control signal of the PLC controller is transmitted to the hydraulic valve group 6. The hydraulic valve group 6 is connected to the PLC controller with an electrical signal and is connected to the hydraulic station and the hoist brake 1.1 through a hydraulic pipeline. Specifically, the oil pressure control signal in the control unit 5 controls the proportional relief valve 6.1 with an analog quantity and controls the solenoid valve 6.2 with a digital quantity.

[0048] Preferably, the control unit 5 and the hydraulic valve group 6 (including the oil pressure sensor 6.5) are assembled in a box and placed next to the hydraulic station.

[0049] The working principle of the system for realizing load-dependent braking of a mine hoist in the utility model is described in detail as follows:

[0050] The speed sensor 4.1 in the sensor unit 4 detects the rotation speed of the hoist 1, the current transformer 4.2 detects the current of the hoist main motor 2, the voltage transformer 4.3 detects the voltage of the hoist main motor 2, and the oil pressure sensor 6.5 detects the oil pressure value of the hydraulic valve group. The speed sensor 4.1, the current transformer 4.2, the voltage transformer 4.3, and the oil pressure sensor 6.5 transmit the detection signals to the PLC controller in the control unit 5.

[0051] The control unit 5 includes a PLC controller installed inside and a touch screen 5.1 installed on the panel. The touch screen 5.1 communicates with the PLC controller to realize human-machine dialogue. Basic parameters are set and the operating status and parameters of the hydraulic valve group 6 are displayed on the touch screen 5.1. The PLC controller calculates the oil pressure control signal based on the speed signal of the speed sensor 4.1, the current signal of the current transformer 4.2 and the voltage signal of the voltage transformer 4.3, and transmits it to the hydraulic valve group 6 and monitors the actual oil pressure of the hydraulic valve group 6 through the oil pressure sensor 6.5.

[0052] When the hoist 1 is in normal working condition, the solenoid valve 6.2 is energized, its A, B, P, T ports are disconnected and the oil circuit is cut off, and the control signal of the proportional relief valve 6.1 is zero; when the hoist is open, the oil pressure output by the hoist hydraulic station 3 through the oil pipeline 8 gradually increases to the hoist brake 1.1 open, and at the same time, the hoist hydraulic station 3 also charges the accumulator 6.3 through the oil pipeline 8, the hydraulic pipeline 7, and the one-way valve 6.4. When the oil pressure value of the accumulator 6.3 reaches the open oil pressure value, the oil filling stops and the hydraulic oil is stored. When the hoist is braked, due to the one-way flow effect of the one-way valve 6.4 and the disconnected and cut-off effect of the A, B, P, T ports of the solenoid valve 6.2, the oil volume and oil pressure of the accumulator 6.3 will not change due to the decrease in the output oil pressure of the hoist hydraulic station 3.

[0053] When the safety brake of the hoist 1 occurs, the oil circuit connected to the hoist brake 1.1 in the hoist hydraulic station 3 is cut off (which can be achieved by controlling the existing solenoid valve in the hoist hydraulic station 3), and the hydraulic oil in the hoist brake 1.1 cannot directly return to the hoist hydraulic station 3, and needs to return oil to the return oil tank of the hoist hydraulic station 3 through the hydraulic valve group 6. The PLC controller in the control unit 5 controls the solenoid valve 6.2 to lose power and controls the proportional relief valve 6.1 to control the oil pressure value according to the analog signal size corresponding to the calculated braking force. Since this oil pressure value is obtained based on the load of this lift, the instantaneous speed during safety braking, and the actual stroke of the lifting container, braking with load-dependent braking force is achieved. That is, when safety braking occurs, the oil circuit of the solenoid valve 6.2 is connected, and the proportional valve 6.1 controls the oil pressure value according to the received control signal, so that the hydraulic oil in the hoist brake 1.1 flows back to the return oil tank of the hoist hydraulic station 3 through the hydraulic pipeline 7, the solenoid valve 6.2, the proportional valve 6.1 and the return oil pipe 9. At the same time, part of the hydraulic oil in the accumulator 6.3 also flows back to the return oil tank of the hoist hydraulic station 3 through the solenoid valve 6.2, the proportional valve 6.1 and the return oil pipe 9.

[0054] During the safety braking process, the oil pressure sensor 6.5 on the hydraulic valve group 6 detects the actual oil pressure value in real time and transmits it to the PLC controller in the control unit 5 for calculation and judgment, and an alarm is issued when abnormal operation occurs.

[0055] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A system for implementing load-dependent braking of a mine hoist, characterized in that: It includes a sensor unit, a control unit and a hydraulic valve group, wherein the sensor unit is used to detect the rotation speed of the hoist, the current and voltage of the hoist main motor and the oil pressure of the hydraulic valve group, and transmits the detected signal to the control unit; the control unit is used to receive the signal from the sensor unit and generate an oil pressure control signal according to the received signal and transmit it to the hydraulic valve group; the hydraulic valve group is connected to the control unit, the hoist hydraulic station and the hoist brake, and controls the oil pressure value of the hoist brake in real time according to the oil pressure control signal sent by the control unit.

2. The system for implementing load-dependent braking of a mine hoist according to claim 1, characterized in that: The hydraulic valve group includes an energy storage part and a control part, wherein the energy storage part includes a pressure gauge, a one-way valve and an accumulator connected in sequence through pipelines along the flow direction of the oil, and the oil pressure sensor of the sensor unit for detecting the oil pressure of the hydraulic valve group is located between the pressure gauge and the one-way valve; the output end of the energy storage part is connected to the control part, and the input end is connected to the pipeline for conveying oil from the hoist hydraulic station to the hoist brake through a hydraulic pipeline, so that when the hoist is working normally, part of the oil output by the hoist hydraulic station is conveyed to the hoist brake, and the other part is conveyed to the accumulator to fill the accumulator with oil; when the hoist brake is safely braked, the oil in the hoist brake is returned to the hoist hydraulic station through the hydraulic valve group; the control part is used to realize the opening and closing of the return oil channel of the hydraulic valve group to the hoist hydraulic station and the oil pressure of the hydraulic valve group when returning oil to the hoist hydraulic station.

3. The system for implementing load-dependent braking of a mine hoist according to claim 2, characterized in that: The control part includes a solenoid valve and a proportional valve, wherein the T port of the solenoid valve is connected to the inlet of the proportional valve, and the outlet of the proportional valve is connected to the oil return tank of the hoist hydraulic station; the B port of the solenoid valve is connected to the outlet of the accumulator and the one-way valve at the same time, and the A port is connected to the oil pressure sensor; and when the solenoid valve is energized, its A, B, P, and T ports are not connected to each other and the oil circuit is cut off, and when the solenoid valve is de-energized, both the A port and the B port are connected to the T port.

4. The system for implementing load-dependent braking of a mine hoist according to claim 3, characterized in that: The sensor unit also includes a speed sensor installed on the hoist and connected to the hoist main shaft, and a current transformer and a voltage transformer installed beside the hoist main motor and connected to the main circuit of the hoist main motor.

5. The system for implementing load-dependent braking of a mine hoist according to claim 4, characterized in that: The control unit comprises a PLC controller for receiving signals from the sensor unit and sending oil pressure control signals to the hydraulic valve group, and a touch screen capable of human-machine dialogue with the PLC controller.

6. The system for implementing load-dependent braking of a mine hoist according to claim 5, characterized in that: The oil pressure control signal includes an analog control signal for controlling a proportional relief valve and a digital control signal for controlling a solenoid valve.

7. The system for implementing load-dependent braking of a mine hoist according to claim 5, characterized in that: The control unit and the hydraulic valve group are located in a box next to the hydraulic station.

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