Automatic gas concentration adjusting system

Abstract

The utility model discloses an automatic gas concentration adjusting system, and belongs to the technical field of gas detection. Comprising a driver; the all-in-one machine comprises a human-computer interface and a control terminal of a programmable logic controller, and the all-in-one machine is connected with the driver; the proximity switch is connected with the all-in-one machine; the gas control part is connected with the all-in-one machine; the stepping motor is connected with the driver; the quantitative injector is fixed on a screw rod of the stepping motor; and the driver is used for driving the quantitative injector to finish air exhaust and air intake. The technical scheme has the beneficial effects that gases with different concentrations can be prepared according to actual requirements on site, the calibration of the gas detector is completed, errors caused by manual operation are avoided, and the calibration precision and the use safety of equipment are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of gas detection, in particular to a gas concentration automatic adjustment system. Background Art

[0002] As my country's requirements for safe gas operation continue to increase, the factory adjustment requirements for gas alarms in gas detector production sites are also becoming increasingly strict. GB 15322 clearly stipulates the range indication deviation range of gas detectors. In order to produce "high", "precise" and "advanced" products, some gas alarm manufacturers strictly control the production and quality control links. The production process is promoted by precise jigs and strict processes, and the adjustment of the alarm is inevitable after assembly. The gas detector is calibrated by on-site operators through the ratio and confirmation of gases of different concentrations. However, the calibration of the gas detector may affect the consistency of the gas ratio due to inconsistent operations and the current status of the operator, affecting the calibration accuracy and safety of the equipment. Utility Model Content

[0003] The purpose of this utility model is to provide a gas concentration automatic adjustment system to solve the above technical problems;

[0004] A gas concentration automatic adjustment system, comprising:

[0005] Driver;

[0006] An all-in-one machine, which is a control terminal including a human-machine interface and a programmable logic controller, and is connected to the driver;

[0007] A proximity switch connected to the all-in-one machine;

[0008] A gas control unit connected to the all-in-one machine;

[0009] a stepper motor connected to the driver;

[0010] A quantitative syringe is fixed on the screw rod of the stepping motor;

[0011] The driver is used to drive the quantitative injector to complete exhaust and intake.

[0012] Preferably, the first digital output interface of the all-in-one machine is connected to the pulse positive input interface, pulse negative input interface, direction signal negative input interface, and enable positive input interface of the driver respectively;

[0013] The pulse positive input interface of the driver is connected to the direction signal positive input interface.

[0014] Preferably, the positive end of the A-phase coil of the stepper motor is connected to the first output interface of the driver, the negative end of the A-phase coil of the stepper motor is connected to the second output interface of the driver, the positive end of the B-phase coil of the stepper motor is connected to the third output interface of the driver, and the negative end of the B-phase coil of the stepper motor is connected to the fourth output interface of the driver.

[0015] Preferably, the first common end of the all-in-one machine is connected to the proximity switch, and the first digital input interface of the all-in-one machine is connected to the proximity switch.

[0016] Preferably, the gas concentration automatic adjustment system includes a manual mode and an automatic mode.

[0017] Preferably, the gas control unit includes:

[0018] an air extraction solenoid valve, wherein a first end of the air extraction solenoid valve is connected to the positive terminal of the power conversion unit, and a second end of the air extraction solenoid valve is connected to the third digital output interface of the all-in-one machine;

[0019] An exhaust solenoid valve, wherein a first end of the exhaust solenoid valve is connected to the positive terminal of the power conversion unit, and a second end of the exhaust solenoid valve is connected to the second digital output interface of the all-in-one machine.

[0020] Preferably, the second common terminal of the all-in-one machine is connected to the negative terminal of the power conversion unit.

[0021] Preferably, it further comprises an audible and visual alarm, which is connected to the gas control unit and the driver.

[0022] Preferably, the proximity switch is a photoelectric switch.

[0023] The beneficial effects of the utility model are: being able to configure gases of different concentrations according to actual requirements on site, completing the calibration of the gas detector, avoiding errors caused by manual operation, and improving the calibration accuracy and use safety of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a circuit diagram of the gas concentration automatic adjustment system of the utility model;

[0025] Figure 2 This is a connection block diagram of the gas concentration automatic adjustment system of the utility model;

[0026] Figure 3 It is a ladder diagram of the starting step of the program of the present utility model;

[0027] Figure 4 This is the ladder diagram of the program steps 55 to 61 of the present invention;

[0028] Figure 5 This is the ladder diagram of the program steps 70 to 102 of the present invention;

[0029] Figure 6 This is the ladder diagram of the program steps 103 to 129 of the present invention;

[0030] Figure 7 This is the ladder diagram of the program steps 130 to 152 of the present invention;

[0031] Figure 8 This is the ladder diagram of the program steps 153 to 181 of the present invention;

[0032] Figure 9 This is the ladder diagram of the program from step 182 to step 207 of the present invention;

[0033] Figure 10 This is the ladder diagram of the program steps 211 to 247 of the present invention;

[0034] Figure 11 This is the ladder diagram of the program steps 248 to 265 of the present invention;

[0035] Figure 12 This is the ladder diagram of the program steps 266 to 285 of the present invention;

[0036] Figure 13 This is the ladder diagram for step 286 to step 319 of the program of the present invention;

[0037] Figure 14 This is the ladder diagram of the program from step 328 to step 351 of the present invention;

[0038] Figure 15 This is the ladder diagram of the program steps 352 to 380 of the present invention;

[0039] Figure 16 This is the ladder diagram of the program from step 381 to step 413 of the present invention;

[0040] Figure 17 This is the ladder diagram of the program from step 414 to step 431 of the present invention;

[0041] Figure 18 This is an interface diagram of the gas concentration automatic adjustment system of the present utility model. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0043] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features therein can be combined with each other.

[0044] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0045] A gas concentration automatic adjustment system, such as Figure 1 、 Figure 2 Shown, including,

[0046] Driver 3;

[0047] All-in-one machine 4, which is a control terminal including a human-machine interface and a programmable logic controller, and is connected to the driver 3;

[0048] Proximity switch 5, connected to all-in-one machine 4;

[0049] A gas control unit 6 connected to the integrated machine 4;

[0050] Stepper motor 7, connected to driver 3;

[0051] The quantitative syringe 9 is fixed on the screw rod of the stepping motor 7;

[0052] The driver 3 is used to drive the quantitative injector 9 to complete exhaust and intake.

[0053] Specifically, the present invention provides an automatic gas concentration adjustment system that utilizes a PLC (Programmable Logic Controller) touchscreen integrated device to control a driver 3. The entire process is accomplished through auxiliary components, including a gas control unit 6 and a proximity switch 5. This device can be configured with gases of varying concentrations according to actual site requirements. Combined with a calibration device, it can calibrate gas detectors, avoiding errors caused by manual operation and improving calibration accuracy and operational safety.

[0054] Specifically, the MD542 stepper driver is used as driver 3. The MD542 is a widely used motion controller that provides high-precision and high-stability stepper motor control. It controls the speed, direction, and pulse waveform of the stepper motor 7, ensuring precise positioning and achieving automated control. Furthermore, it offers advantages such as energy conservation, high efficiency, and low noise.

[0055] More specifically, the all-in-one machine 4 of the present invention includes the relevant performance of HMI (human-machine interface) and PLC. You can choose the corresponding series according to the complexity of your program. Figure 18 The page includes manual adjustment area and automatic adjustment area. The manual adjustment area is equipped with start and stop buttons, manual air extraction button and manual exhaust button. The automatic adjustment area can set the input concentration. The automatic adjustment area is equipped with a start button, intake valve control button, exhaust valve control button and reset button. The corresponding element diagram can be assigned and set through simple software construction.

[0056] More specifically, the stepper motor 7 of the present invention is an electric motor that converts electrical pulse signals into corresponding angular or linear displacements. Each time a pulse signal is input, the rotor rotates one degree or advances one step. The output angular or linear displacement is proportional to the number of input pulses, and the rotational speed is proportional to the pulse frequency.

[0057] In a preferred embodiment, the first digital output interface Y0 of the all-in-one machine 4 is connected to the pulse positive input interface PUL+, the pulse negative input interface PUL-, the direction signal negative input interface DIR-, and the enable positive input interface ENA- of the driver 3 respectively;

[0058] Connect the pulse positive input interface PUL+ of driver 3 to the direction signal positive input interface DIR+;

[0059] The positive voltage pin V+ of the driver 3 is connected to the positive terminal DC_24V+ of the power conversion unit 2, and the ground pin GND of the driver 3 is connected to the negative terminal DC_24V- of the power conversion unit 2;

[0060] The positive end of the A-phase coil of the stepper motor 7 is connected to the first output interface A+ of the driver 3, the negative end of the A-phase coil of the stepper motor 7 is connected to the second output interface A- of the driver 3, the positive end of the B-phase coil of the stepper motor 7 is connected to the third output interface B+ of the driver 3, and the negative end of the B-phase coil of the stepper motor 7 is connected to the fourth output interface B- of the driver 3;

[0061] The positive power input terminal of the all-in-one machine 4 is connected to the positive terminal DC_24V+ of the power conversion unit 2, and the negative power input terminal of the all-in-one machine 4 is connected to the negative terminal DC_24V- of the power conversion unit 2;

[0062] The first common terminal COM of the all-in-one machine 4 is connected to the proximity switch 5, the first digital input interface X1 of the all-in-one machine 4 is connected to the proximity switch 5, and the proximity switch 5 is also connected to the positive terminal DC_24V+ of the power conversion unit 2;

[0063] The gas control unit 6 includes:

[0064] The exhaust solenoid valve 61 has a first end connected to the positive terminal DC_24V+ of the power conversion unit 2 and a second end connected to the third digital output interface Y6 of the all-in-one machine 4;

[0065] An exhaust solenoid valve 62 , wherein a first end of the exhaust solenoid valve 62 is connected to the positive terminal DC_24V+ of the power conversion unit 2 , and a second end of the exhaust solenoid valve 62 is connected to the second digital output interface Y4 of the all-in-one machine 4 ;

[0066] The second common terminal COM2 of the integrated machine 4 is connected to the negative terminal DC_24V- of the power conversion unit 2 .

[0067] Specifically, the input end of the power conversion unit 2 is connected to the AC power plug 1, the driver 3 is connected to the output end of the power conversion unit 2, the all-in-one machine 4 is connected to the output end of the power conversion unit 2 and the driver 3, the proximity switch 5 is connected between the output end of the power conversion unit 2 and the all-in-one machine 4, and the gas control unit 6 is connected between the output end of the power conversion unit 2 and the all-in-one machine 4.

[0068] The first input terminal of the power conversion unit 2 is connected to the live wire L of the mains plug 1, and the second input terminal of the power conversion unit 2 is connected to the neutral wire N of the mains plug 1. This adjustment device uses the Zhongda MC-40MR-12MT-700-FX-A integrated control unit as the display and control unit. Based on practicality, it has two functional modes: manual and automatic. In manual mode, the syringe origin can be adjusted using the proximity switch 5. This prevents errors in the origin caused by the stepper motor 7's prolonged reset. The function buttons in manual mode can be used to test the proper operation of system components. Once preparation is complete, the system can switch to automatic mode. The desired gas concentration and volume are entered in the corresponding area of the display. The control unit calculates the number of revolutions and lead of the stepper motor 7 using an imported program. Output contacts control the opening and closing of the exhaust solenoid valve 61 and exhaust solenoid valve 62, controlling the DM542 driver 3 to drive the stepper motor 7, which in turn drives the metered-dose syringe 9 mounted on the lead screw. Repeated exhaust and extraction accumulates a counter in the program. When the accumulated number reaches a predetermined value, the device stops and the corresponding completion indicator is triggered. Finally, the gas concentration matching process is completed.

[0069] In a preferred embodiment, an audible and visual alarm 8 is further included, and the audible and visual alarm 8 is connected to the gas control unit 6 and the driver 3 .

[0070] Specifically, when a preset condition is detected (for example, the gas concentration exceeds a safety threshold), an alarm is issued to the operator through sound and light. The gas control unit 6 and the driver 3 are combined to achieve automatic adjustment and safety control of the gas concentration.

[0071] In a preferred embodiment, the proximity switch 5 is a photoelectric switch.

[0072] Specifically, the presence or position of an object is detected through the photoelectric effect. A photoelectric switch typically consists of a light source (such as an infrared LED) and a receiver (a photodiode or phototransistor). When the detected object blocks the light beam, the photoelectric switch generates an output signal that is fed back to the integrated device 4.

[0073] Because different gases require different amounts of gas for distribution, the gas distribution process after the injection device automatically calculates the gas distribution needs to be considered during the design process. In one embodiment, the syringe is set to pump out 50ml of air at a time. When the demand is 40ml, the number of motor pulses can be adjusted to complete the process within a single cycle. When the demand is 400ml, the calculation shows that the syringe needs to work back and forth eight times to finally reach the target concentration. During this process, a counter is added to record the value. When the counter records the value of 8 times, the gas distribution experiment is complete.

[0074] Reference Figures 3 to 17 In the figure, M0 represents the start button, M1 represents manual mode, M50 represents manual extraction, M51 represents manual exhaust, M60 represents emergency stop, M200 represents extraction, M201 represents exhaust, M300 represents reset, M8002 represents power-on, X001 represents proximity switch 5, Y000 represents pulse, Y002 represents direction, Y004 represents exhaust valve, Y006 represents intake valve, Y010 represents start indicator light, Y011 represents triggering when the comparison value is less than 51, Y012 represents triggering when the comparison value is greater than 52, D0 represents gas concentration input, D8140 represents recording the current position when the pulse is output by Y0, and C0 represents counter.

[0075] Specifically, Figure 3 During the exhaust cycle, turn on the manual mode switch M1, press and hold the exhaust button M200, open the intake valve Y006, delay 0.5s, and assign the value -6200 to D100. During the exhaust cycle, turn on the manual mode switch M1, press and hold the exhaust button M201, open the exhaust valve Y004, reset Y006, delay 0.5s, and assign the value 6200 to D100. Figure 3 When the T21 timer is on and the proximity switch is not triggered, or when the T20 timer is on and the start button is not triggered, internal relay M210 is energized. After internal relay M210 is energized, the absolute control instruction DRVA adjusts the pulse count (desired lead) in D100 to a pulse frequency of 1600 (controlling the motor's rotational speed). External relay Y000 is energized in the direction of Y002, driving the lead screw through the speed regulator. Simultaneously with the triggering of proximity switch 5, the exhaust valve is reset.

[0076] Figure 5In the comparison instruction CMPP, when the concentration input D1 value is greater than 0, M10 is turned on; when the concentration input D1 value is equal to 0, S20 is turned on. Figure 6 When D1 is less than 51, M100 is turned on and Y011 is turned on. When D1 is greater than 52, M102 is turned on and Y012 is turned on. Figure 7 In the multiplication operation, the value of the D1 register is multiplied by 124 and the result is transferred to the D2 register. In the subtraction operation, the value of the D2 register is negative and the result is transferred to the D3 register. Figure 8 The stepping instruction S24 is turned on, and the absolute control instruction DRVA is used to adjust the number of pulses to be output in D3 (the desired lead) to a pulse frequency of 1600 (to control the motor's rotation speed). The Y000 external relay is turned on in the opposite direction of Y002, thereby driving the lead screw through the speed regulator. Figure 9 The stepping instruction S25 is turned on, and the absolute control instruction DRVA is used to adjust the number of pulses to be output in D2 (the desired lead) to a pulse frequency of 1600 (to control the motor's rotation speed). According to the direction of Y002, the Y000 external relay is turned on, thereby driving the lead screw through the speed regulator. Figure 10 Integer division operation: divide the value of register D1 by 50 and transfer the result to register D12; multiplication operation: multiply the value of register D12 by 50 and transfer the result to register D13; subtraction operation: subtract the value of register D13 from the value of register D10 and transfer the result to register D14. Figure 12 The stepping instruction S31 is turned on, and through the absolute control instruction DRVA, the number of pulses output is 6200 (the desired lead) and the pulse frequency is 1600 (to control the rotation speed of the motor). Pressing the opposite direction of Y002, the Y000 external relay is turned on, thereby driving the lead screw through the speed regulator. Figure 13 Stepper instruction S32 is activated, and the absolute control instruction DRVA outputs a pulse count of 6200 (the desired lead) at a pulse frequency of 1600 (to control the motor's rotational speed). External relay Y000 is activated in the direction of Y002, driving the lead screw through the speed regulator. Upon completion of a cycle, the counter counts until the value equals D12, at which point counter C0 is activated. If counter C0 is inactive, stepper loop S33 continues. If counter C0 is active, stepper loop S41 is executed. Figure 14 Multiplication operation: multiply the value of the D14 register by 124 and transfer the result to the D15 register; subtraction operation: negate the value of the D15 register and transfer the result to the D16 register. Figure 15The stepping instruction S34 is turned on, and the absolute control instruction DRVA is used to adjust the number of pulses to be output in D16 (the desired lead) to a pulse frequency of 1600 (to control the motor's rotation speed). The Y000 external relay is turned on in the opposite direction of Y002, thereby driving the lead screw through the speed regulator. Figure 16 The stepping instruction S35 is turned on, and the absolute control instruction DRVA is used to adjust the number of pulses to be output in D15 (the desired lead) to a pulse frequency of 1600 (to control the motor's rotation speed). The Y000 external relay is turned on in the opposite direction of Y002, thereby driving the lead screw through the speed regulator.

[0077] In a preferred embodiment, the gas concentration automatic adjustment system includes manual mode control and automatic mode control.

[0078] Specifically, turning on the manual mode button M1 and pressing the exhaust (M200) and exhaust (M201) buttons opens the corresponding solenoid valves. Through the delayed conduction effect of T20 and T21, pulse assignment is performed after the solenoid valves open, driving the stepper motor. When the slider triggers the predetermined proximity switch 5, the proximity switch 5's signal X001 closes, and the stepper motor 7 stops, completing the syringe origin adjustment. This prevents gas configuration errors caused by the machine's origin shift due to long-term operation. This also effectively evacuates any remaining impurities in the pipeline through gas circulation.

[0079] Specifically, turn off the manual mode button M1, enter the desired gas volume in the D1 concentration input area, and press the start button M0. The built-in program then calculates the number of reciprocating motions of stepper motor 7. Upon completion, the Y6 intake solenoid valve opens, while the slider drives the syringe to pump gas. When the gas is pumped to the desired lead, the Y6 intake solenoid valve closes and the Y4 exhaust solenoid valve opens. Stepper motor 7 then reverses direction, exhausting the gas from the syringe to its initial state. Counter C0 then counts once. If the current counter C0 count is less than the internally calculated absolute value D12, the next pumping and exhausting cycle repeats until the counter C0 count equals the internally calculated absolute value D12. This completes the integer pumping count. Next, the non-integer multiples of the fractions D15 and D16 are calculated. When the values of D15 and D16 equal 0, the configuration is completed, triggering the Y7 buzzer to indicate that the gas concentration configuration is complete. If the values of D15 and D16 are greater than 0, stepper motor 7 will reciprocate according to the lead of D15 and D16. When completed, the Y7 buzzer will beep to indicate that the current gas concentration configuration is complete. If the corresponding gas needs to be changed during configuration, simply press the M300 reset button to restore the system to its original state.

[0080] In summary, the present application provides a gas concentration automatic adjustment system that specifically adopts high-precision gas security detectors with automatic adjustment and manual adjustment functions to avoid deviations caused by operations of different operators and improve the calibration accuracy and safety of the equipment.

[0081] The above description is only a preferred embodiment of the present invention and does not limit the implementation method and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A gas concentration automatic adjustment system, characterized in that: include, Driver (3); An all-in-one machine (4), the all-in-one machine (4) being a control terminal including a human-machine interface and a programmable logic controller, the all-in-one machine (4) being connected to the driver (3); A proximity switch (5) connected to the all-in-one machine (4); A gas control unit (6) connected to the integrated machine (4); a stepper motor (7), connected to the driver (3); A quantitative syringe (9) is fixed on the screw rod of the stepping motor (7); The driver (3) is used to drive the quantitative injector (9) to complete exhaust and intake.

2. The gas concentration automatic adjustment system according to claim 1, characterized in that: The first digital output interface (Y0) of the all-in-one machine (4) is respectively connected to the pulse positive input interface (PUL+), the pulse negative input interface (PUL-), the direction signal negative input interface (DIR-), and the enable positive input interface (ENA-) of the driver (3); The pulse positive input interface (PUL+) of the driver (3) is connected to the direction signal positive input interface (DIR+).

3. The gas concentration automatic adjustment system according to claim 1, characterized in that: The positive terminal of the A-phase coil of the stepper motor (7) is connected to the first output interface (A+) of the driver (3), the negative terminal of the A-phase coil of the stepper motor (7) is connected to the second output interface (A-) of the driver (3), the positive terminal of the B-phase coil of the stepper motor (7) is connected to the third output interface (B+) of the driver (3), and the negative terminal of the B-phase coil of the stepper motor (7) is connected to the fourth output interface (B-) of the driver (3).

4. The gas concentration automatic adjustment system according to claim 1, characterized in that: The first common terminal (COM) of the all-in-one machine (4) is connected to the proximity switch (5), and the first digital input interface (X1) of the all-in-one machine (4) is connected to the proximity switch (5).

5. The gas concentration automatic adjustment system according to claim 1, characterized in that: The gas concentration automatic adjustment system includes a manual mode and an automatic mode.

6. The gas concentration automatic adjustment system according to claim 1, characterized in that: The gas control unit (6) includes: An air extraction solenoid valve (61), wherein a first end of the air extraction solenoid valve (61) is connected to the positive terminal (DC_24V+) of the power conversion unit (2), and a second end of the air extraction solenoid valve (61) is connected to the third digital output interface (Y6) of the all-in-one machine (4); An exhaust solenoid valve (62), wherein a first end of the exhaust solenoid valve (62) is connected to the positive terminal (DC_24V+) of the power conversion unit (2), and a second end of the exhaust solenoid valve (62) is connected to the second digital output interface (Y4) of the all-in-one machine (4).

7. The gas concentration automatic adjustment system according to claim 6, characterized in that: The second common terminal (COM2) of the all-in-one machine (4) is connected to the negative terminal (DC_24V-) of the power conversion unit (2).

8. The gas concentration automatic adjustment system according to claim 1, characterized in that: It also includes an audible and visual alarm (8), which is connected to the gas control unit (6) and the driver (3).

9. The gas concentration automatic adjustment system according to claim 1, characterized in that: The proximity switch (5) is a photoelectric switch.

Images