Gas sampler for coal mine

Abstract

The utility model discloses a gas sampler for a coal mine, which comprises a shell, a pagoda connector is fixedly connected to the outer wall of one side of the shell, and the pagoda connector comprises a gas outlet and a gas inlet; an air pump is fixedly connected to the inner wall of the bottom of the shell, the same three-way pipe is connected between the air inlet end of the air pump and the air inlet, and one end of the three-way pipe is connected with an air pressure sensor A fixedly connected to the inner wall of one side of the shell; the air pump comprises a pump head, a motor, an air cylinder, a piston and a transmission crankshaft, valves are arranged on the outer walls of the air inlet end and the air outlet end of the air pump respectively, and the motor is connected with the battery through a wire. According to the coal mine gas sampling device, the coal mine gas can be rapidly, accurately and conveniently sampled through one-button operation, the functions of real-time monitoring and the like are achieved, the gas sampling efficiency is improved, the influence of human factors on the sampling result is avoided, the accuracy of the measurement result is ensured, and more powerful technical guarantee is provided for coal mine safety production.

Description

Technical Field

[0001] The utility model relates to the technical field of gas sampling, in particular to a gas sampler for coal mines. Background Art

[0002] Gases such as gas and carbon monoxide are one of the important factors for coal mine safety. Therefore, gas detection is generally taken as an important indicator in aspects such as fire detection and safety detection in coal mine safety production. In coal mine production and safety management, gas sampling and analysis are key links for preventing gas explosions, monitoring the air quality underground, and ensuring the health and safety of miners.

[0003] Traditional gas sampling methods for coal mines mostly rely on manual operations, such as using mechanical manual gas collection devices such as double-connected balls and rubber bladder balls. These methods are not only time-consuming and laborious with low work efficiency, but also easily affected by external interference during the gas sample collection process, resulting in inaccurate measurement results. For this reason, we propose a gas sampler for coal mines that is more labor-saving and can complete efficient collection work. Content of the Utility Model

[0004] The purpose of the utility model is to solve the deficiencies existing in the prior art, and propose a gas sampler for coal mines.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A gas sampler for coal mines includes a housing. One outer wall of the housing is fixedly connected with a tower interface, and the tower interface includes an air outlet and an air inlet; a gas pump is fixedly connected to the bottom inner wall of the housing. A three-way pipe is connected between the air inlet end of the gas pump and the air inlet, and one end of the three-way pipe is connected to a pressure sensor A fixedly connected to one inner wall of the housing.

[0007] The gas pump includes a pump head, a motor, a cylinder, a piston and a transmission crankshaft, and valves are respectively arranged on the outer walls of the air inlet end and the air outlet end of the gas pump. The motor is connected to a battery through a wire.

[0008] As a further scheme of the utility model: a display screen is fixedly connected to one outer wall of the housing.

[0009] As a further scheme of the utility model: a switch is fixedly connected to one outer wall of the housing.

[0010] As a further scheme of the utility model: a battery is fixedly connected to the bottom inner wall of the housing;

[0011] A charging port is fixedly connected to one outer wall of the housing.

[0012] As a further solution of the utility model: a temperature sensor is fixedly connected to the inner wall of one side of the housing, and the temperature sensor is connected to a circuit board fixedly connected to the inner wall of the bottom of the housing through a cable.

[0013] As a further solution of the utility model: the control system of the motor includes chip control, current limiting control and constant current control.

[0014] As a further solution of the utility model: an air bag is arranged on the outer wall of one side of the housing, the air inlet end of the air bag is connected to the air outlet through a conduit, and a pressure sensor B is fixedly connected to the outer wall of the air bag.

[0015] As a further solution of the utility model: a top cover is fixedly connected to the top surface of the housing, and a handle is rotatably connected to the inner wall of the top of the top cover.

[0016] As a further solution of the utility model: a lighting lamp is fixedly connected to the outer wall of one side of the housing; a nameplate is fixedly connected to the outer wall of one side of the housing.

[0017] Compared with the prior art, the utility model provides a gas sampler for coal mines, which has the following beneficial effects:

[0018] 1. For this gas sampler for coal mines, by setting structures such as an air pump, during operation, the motor drives the piston of the cylinder to move, generating negative pressure in the cylinder, so as to draw external gas into it through the air inlet. When the piston moves in the reverse direction, the intake valve closes and the exhaust valve opens, so that the gas is compressed and pushed into the air bag for collection. The one-key operation realizes the rapid, accurate and convenient sampling of coal mine gas, and has functions such as real-time monitoring. It not only improves the sampling efficiency of the gas, but also avoids the influence of human factors on the sampling result, ensuring the accuracy of the measurement result and providing a more powerful technical guarantee for coal mine safety production.

[0019] 2. This gas sampler for coal mines adopts a one-key trigger switch button, without pressure drop, and will not affect the start-stop performance of the air pump due to wear during long-term use; it is equipped with an internal pressure sensor A and a temperature sensor, and can be displayed on the display screen, allowing users to more clearly understand the current instrument status and assist in making reasonable operations; it adopts a double protection circuit of cross current plus current limiting, which can limit the current of the air pump and control the power of the air pump in case of abnormal conditions of the air pump, avoiding the air pump from being burned out and improving the use safety.

[0020] 3. The gas sampler for coal mines directly powers a high-power motor with a battery, and a constant current circuit and a current limiting circuit are added to the motor control circuit, aiming to improve the vacuum degree and gas flow value of the device. The constant current value of the added constant current circuit is slightly lower than the current value of the current limiting circuit to ensure that the current limiting circuit takes effect when the constant current circuit fails and is also below the maximum output current of the energy control board. In addition, the present utility model adds functions of air pressure and temperature detection, which can measure the ambient air pressure of the environment or the extraction area and detect the negative pressure vacuum value of the pipeline environment in real time. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 FIG. is a schematic side view structure diagram of a gas sampler for coal mines proposed by the present utility model;

[0022] Figure 2 FIG. is a schematic side view structure diagram of another side of a gas sampler for coal mines proposed by the present utility model;

[0023] Figure 3 FIG. is a schematic top view structure diagram of the housing of a gas sampler for coal mines proposed by the present utility model;

[0024] Figure 4 FIG. is a schematic diagram of the motor control principle of a gas sampler for coal mines proposed by the present utility model.

[0025] In the figure: 1 housing, 2 top cover, 3 handle, 4 display screen, 5 switch, 6 charging port, 7 air outlet, 8 air inlet, 9 nameplate, 10 air bag, 11 battery, 12 air pump, 13 air pressure sensor A, 14 three-way pipe, 15 circuit board, 16 temperature sensor. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments.

[0027] Embodiment 1

[0028] A gas sampler for coal mines, as Figures 1-3 shown, includes a housing 1. The top surface of the housing 1 is fixedly connected with a top cover 2 by bolts. The inner wall of the top of the top cover 2 is rotatably connected with a handle 3 for facilitating the carrying of the device; a device prompt nameplate 9 is fixedly connected to the outer wall of one side of the housing 1 by bolts;

[0029] Furthermore, a display screen 4 for displaying the battery 11 power, extraction negative pressure, temperature and other parameters, a switch 5 for controlling the start and stop of the device, a charging port 6 for replenishing the battery 11 power, and a pagoda interface for connecting the air circuit of the air pump 12 are fixedly connected to the outer wall of one side of the housing 1, and the pagoda interface includes an air outlet 7 and an air inlet 8;

[0030] Furthermore, a battery 11 connected to a wire of the charging port 6 is fixed to the bottom inner wall of the shell 1 by bolts, and the preferred battery 11 is a lithium battery; an air pump 12 for extracting gas is fixed to the bottom inner wall of the shell 1 by bolts, and a same three-way pipe 14 is connected between the air inlet end of the air pump 12 and the air inlet 8, and one end of the three-way pipe 14 is connected to an air pressure sensor A13 fixedly connected to an inner wall of one side of the shell 1; the air pressure sensor A13 is configured to measure changes in the pressure of the sampled gas to ensure that the air pump 12 can accurately reach the preset air pressure.

[0031] Further preferably, the air pump 12 includes a pump head, a high-power motor, a cylinder, a piston and a transmission crankshaft, and valves are respectively provided on the outer walls of the air inlet and outlet ends of the air pump 12. The motor is connected to the battery 11 through a wire, which is not repeated here as in the prior art. The motor is a brushless motor. When the air pump 12 is operating, the motor drives the cylinder piston to move, so that negative pressure is generated in the cylinder, thereby drawing external gas into it through the air inlet 8. When the piston moves in the opposite direction, the air inlet valve is closed and the air outlet valve is opened, so that the gas is compressed and pushed out to the air bag 10 for collection.

[0032] Furthermore, a temperature sensor 16 is fixed to the inner wall of one side of the shell 1 by bolts, and the temperature sensor 16 is connected to a circuit board 15 fixedly connected to the inner wall of the bottom of the shell 1 through a flat cable. Preferably, the circuit board 15 has a constant current function; it is used to monitor the operating temperature of the circuit board 15.

[0033] Preferably, the display screen 4 , the air pump 12 , the air pressure sensor A13 and the temperature sensor 16 are electrically connected to the control module respectively; so that during the process of collecting environmental gas, people can observe real-time air pressure, temperature and other data through the display screen 4 .

[0034] As a supplement, Figure 4 As shown, the control system of the motor includes chip control, current limiting control and constant current control, wherein the chip control is equivalent to the switch 5 of the motor. After the device is turned on, the chip sends a signal to control the transistor Q4, which drives Q2 and Q3 to turn on, so that the motor circuit is turned on;

[0035] Among them, the current limiting control is a current limiting resistor set between the battery 11 and the air pump 12. A sampling resistor R27 is set in the motor circuit. One end of the sampling resistor R27 is grounded. When current passes through the sampling resistor R27, a voltage will be generated at the other end of the sampling resistor R27. This voltage increases as the current increases, and this voltage value is used to determine whether the current in the motor circuit exceeds the limit. Specifically, the control method of the current limiting control is as follows: A sampling resistor is set in the motor circuit, and the voltage on the sampling resistor is sent to the inverting input terminal of the comparator to be compared with the reference voltage at the non-inverting input terminal. When the current does not reach the upper limit, the comparator outputs a high level, the triode conducts to pull down the control pole of the power mos tube to make the mos tube conduct, and the motor works; when the current reaches the upper limit, the comparator outputs a low level, the mos tube is cut off, and the motor is open-circuited to limit the motor current.

[0036] Among them, the control principle of the constant current control is that a sampling resistor is set in the current loop of the motor. Using the voltage of the sampling resistor, the operational amplifiers U13.1 and U13.2 adjust the output of the operational amplifier according to the voltage of the sampling resistor input to the inverting input terminal and the reference voltage at the non-inverting input terminal, and control the conduction degree of Q9 and Q10. When the current is large, the conduction state of Q9 and Q10 is reduced, the internal resistance is increased to share the power, so that the total resistance in the motor circuit increases. According to Ohm's law, when the resistance increases, the current decreases to control the increasing current; when the current is small, the conduction state of Q9 and Q10 is increased, the internal resistance is reduced to release the power, so that the total resistance in the motor circuit decreases. According to Ohm's law, when the resistance decreases, the current increases to compensate for the decreasing current and maintain the constancy of the power. Specifically, the control method of the constant current control schematic diagram is as follows: A sampling resistor is set in the motor circuit, and the voltage on the sampling resistor is sent to the inverting input terminal of the operational amplifier to be compared with the reference voltage at the non-inverting input terminal. Through the negative feedback adjustment of the operational amplifier, the voltages at the two input terminals are kept the same to perform constant current control. During the constant current process, when the motor is working, current flows through the loop, and a voltage is generated on the sampling resistor. After this voltage enters the negative input terminal of the operational amplifier, it is compared with the reference voltage at the positive input terminal. When it is less than, the voltage at the output terminal of the operational amplifier increases to improve the switching degree of the subsequent mos tube; when it is greater than, the voltage at the output terminal of the operational amplifier decreases to reduce the switching degree of the subsequent mos tube. Through this linear adjustment, constant current control is achieved to limit the current flowing through the loop when the motor fails.

[0037] The control principle of the motor in the air pump 12 is as follows: The positive and negative poles of the battery 11 are respectively connected to the BATTERY label at the upper end and the GND label at the lower end. The current flows through Q2 and Q3 at the chip control label to Q5 and Q6 at the current limiting control, then enters the positive pole of the motor through pin 2 of the J2 terminal and flows out of the negative pole of the motor through pin 1 of J2, and then flows through Q9 and Q10 of the cross-current control part, and then returns to the negative pole of the battery 11 through the sampling resistor R27 to form a complete current loop. In the normal working state, the MOS transistors in the three parts of chip control, current limiting control, and cross-current control are conducting, equivalent to a path, and only in the abnormal state will the current of the motor be controlled by turning off the corresponding MOS transistor.

[0038] Working principle: Hold the handle 3 by hand and press the switch 5 to control the operation of the air pump 12. The motor drives the cylinder piston to move, creating a negative pressure in the cylinder, thereby extracting external gas into it through the air inlet 8. When the piston moves in the reverse direction, the intake valve closes and the exhaust valve opens, so that the gas is compressed and pushed into the air bag 10 for collection.

[0039] The utility model adopts a one-key trigger switch 5 button, without voltage drop, and will not affect the start-stop performance of the air pump 12 due to wear during long-term use; an internal pressure sensor A13 and a temperature sensor 16 are provided and can be displayed on the display screen 4, allowing the user to more clearly understand the current instrument state and assist in making reasonable operations; a double protection circuit of cross-current plus current limiting is adopted, which can limit the current of the air pump 12 and control the power of the air pump 12 in the abnormal situation of the air pump 12, avoid burning out the air pump 12, and improve the use safety.

[0040] Embodiment 2

[0041] A gas sampler for coal mines, as Figure 2 shown. In order to facilitate the collection of sampled gas; the following improvements are made on the basis of Embodiment 1: A gas bag 10 for collecting the sampled gas is adhesively bonded to the outer wall of one side of the housing 1. The intake end of the gas bag 10 is connected to the air outlet 7 through a conduit, and a pressure sensor B for detecting the internal air pressure value of the gas bag 10 is fixedly connected to the outer wall of the gas bag 10; the ambient gas collected by the air pump 12 is transported to the gas bag 10 through the air outlet 7 for collection, and the pressure sensor B detects the air pressure value in the gas bag 10 in real time for people to understand the gas sampling progress. After the sampling is completed, after disconnecting the connection between the gas bag 10 and the air outlet 7, the gas bag 10 can be removed, and the disassembly and assembly are convenient.

[0042] Furthermore, a lighting lamp [not shown in the figure] is fixed to the outer wall of one side of the housing 1 by bolts; it is used to illuminate the environment and increase the use functionality of the device.

[0043] Working principle: The utility model directly powers a high-power motor by a battery 11, and a constant current circuit and a current limiting circuit are added to the motor control circuit, aiming to improve the vacuum degree and gas flow value of the device. The constant current value of the added constant current circuit is slightly lower than the current value of the current limiting circuit, ensuring that the current limiting circuit works when the constant current circuit fails and is also below the maximum output current of the energy control board. In addition, the utility model adds a function of detecting air pressure and temperature, which can measure the ambient air pressure of the environment or the extraction area and detect the negative pressure vacuum value of a pipeline environment in real time.

[0044] The above are only the preferred specific embodiments of the utility model, but the protection scope of the utility model is not limited thereto. Any person skilled in the art within the technical scope disclosed by the utility model, according to the technical solution and the inventive concept of the utility model, making equivalent substitutions or changes should be covered by the protection scope of the utility model.

Claims

1. A gas sampler for coal mines, comprising a housing (1), characterized in that, One side outer wall of the said housing (1) is fixedly connected with a taper interface, and the taper interface includes an air outlet (7) and an air inlet (8); the bottom inner wall of the housing (1) is fixedly connected with an air pump (12), and the same three-way pipe (14) is connected between the air inlet end of the air pump (12) and the air inlet (8), and one end of the three-way pipe (14) is connected with a pressure sensor A (13) fixedly connected to one side inner wall of the housing (1). The said air pump (12) includes a pump head, a motor, a cylinder, a piston and a transmission crankshaft, and valves are respectively arranged on the outer walls of the air inlet end and the air outlet end of the air pump (12), and the motor is connected to a battery (11) through a wire.

2. The gas sampler for coal mines according to claim 1, characterized in that, One side outer wall of the said housing (1) is fixedly connected with a display screen (4).

3. The gas sampler for coal mines according to claim 2, characterized in that, One side outer wall of the said housing (1) is fixedly connected with a switch (5).

4. The gas sampler for coal mines according to claim 3, characterized in that, The bottom inner wall of the said housing (1) is fixedly connected with a battery (11); One side outer wall of the said housing (1) is fixedly connected with a charging port (6).

5. The gas sampler for coal mines according to claim 4, characterized in that, One side inner wall of the said housing (1) is fixedly connected with a temperature sensor (16), and the temperature sensor (16) is connected to a circuit board (15) fixedly connected to the bottom inner wall of the housing (1) through a cable.

6. The gas sampler for coal mines according to claim 5, characterized in that, The control system of the said motor includes chip control, current limiting control and constant current control.

7. The gas sampler for coal mines according to claim 1, wherein, One side outer wall of the said housing (1) is provided with an air bag (10), the air inlet end of the air bag (10) is connected to the air outlet (7) through a conduit, and a pressure sensor B is fixedly connected to the outer wall of the air bag (10).

8. A gas sampler for coal mines according to claim 7, characterized in that, The top surface of the said housing (1) is fixedly connected with a top cover (2), and a handle (3) is rotatably connected to the top inner wall of the top cover (2).

9. The gas sampler for coal mines according to claim 8, characterized in that, One side outer wall of the said housing (1) is fixedly connected with a lighting lamp; one side outer wall of the said housing (1) is fixedly connected with a nameplate (9).

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