A monitoring and alarm device for a feed valve

Abstract

The utility model discloses a kind of monitoring alarm devices of mine valve, the monitoring alarm device includes AC contactor, driving unit, first intermediate relay, second intermediate relay, third intermediate relay, first time relay, second time relay, first detection unit, second detection unit, first indicating unit, second indicating unit, first alarm unit and second alarm unit;Through the cooperation of first detection unit, second detection unit and each relay, pneumatic knife valve can be realized to open to position indication, not open to position alarm, close to position indication and not close to position alarm, abnormal problems of not open to position and not close to position are found in time, so as to find problem in time and solve, avoid the problem of concentrate pollution and process out of control caused by not close to position.

Description

Technical Field

[0001] This utility model belongs to the field of valve monitoring technology, and in particular relates to a monitoring and alarm device for a feed valve. Background Technology

[0002] Centrifugal gravity separation equipment (such as Nelson concentrators) often faces the following problems when using pneumatic knife valves (i.e., feed valves) to control the feed flow: (1) Valve not closing tightly leads to concentrate contamination: Concentrate enrichment in centrifugal gravity separation equipment depends on continuous separation under high centrifugal force field. If the valve is not closed tightly, tailings or middlings are easily mixed into the concentrate, which in turn leads to a decrease in concentrate grade and reduced efficiency. (2) Gas source / solenoid valve failure: Insufficient gas supply or solenoid valve jamming, preventing the valve from closing completely; (3) Particles in the slurry can cause the valve to jam: minerals can easily accumulate in the gap on the opposite side of the valve, while coarse particles or high-concentration slurry can prevent the valve from closing. (4) Wear of the rubber ring or leakage in the gap leads to seal failure.

[0003] These problems are particularly serious during the shutdown and discharge phase: if the valves are not closed tightly, the slurry will flow into the concentrate collection box in the gold cleaning chamber with the discharged ore, causing concentrate contamination; the contaminated concentrate needs to be treated additionally, increasing labor costs; if it is not detected in time, a large amount of slurry will flood into the gold cleaning chamber, even causing the equipment to be shut down for cleaning.

[0004] Valve status feedback errors can lead to systemic risks: for example, if the control system reports "valve is closed" but there is actually a leak, the slurry will directly contaminate the concentrate during ore discharge, and may even paralyze the subsequent shaking table sorting process. In addition, the monitoring of pneumatic knife valves in centrifugal gravity separation equipment relies on manual inspection. Abnormal problems such as valves not closing are difficult to detect in a timely manner, and the lack of timely feedback can easily lead to abnormal unloading for a long time. Utility Model Content

[0005] The purpose of this utility model is to provide a monitoring and alarm device for feed valves to solve the problems of concentrate contamination and process loss caused by the incomplete closure of pneumatic knife valves in centrifugal gravity separation equipment.

[0006] This utility model solves the above-mentioned technical problems through the following technical solution: a monitoring and alarm device for a feed valve, used to monitor the opening and closing status of a pneumatic knife valve in a centrifugal gravity separation equipment, the monitoring and alarm device including an AC contactor, a drive unit for driving the pneumatic knife valve to open or close, a first intermediate relay, a second intermediate relay, a third intermediate relay, a first time relay, a second time relay, a first detection unit, a second detection unit, a first indication unit, a second indication unit, a first alarm unit, and a second alarm unit; The first normally open contact of the AC contactor is used to control the energization or de-energization of the drive unit. The second normally open contact of the AC contactor is connected in series with the coil of the second time relay, and the normally closed contact of the AC contactor is connected in series with the coil of the second intermediate relay. The first normally open contact of the second intermediate relay is connected in series with the coil of the first time relay. The energization or de-energization of the coil of the first intermediate relay is controlled by the detection result of the first detection unit. The normally open contact of the first intermediate relay is connected in series with the first indicator unit. The first normally closed contact of the first intermediate relay, the normally open contact of the second time relay, and the second alarm unit are connected in series. The energization or de-energization of the coil of the third intermediate relay is controlled by the detection result of the second detection unit. The normally open contact of the third intermediate relay is connected in series with the second indicator unit. The first normally closed contact of the third intermediate relay, the normally open contact of the first time relay, and the first alarm unit are connected in series.

[0007] In the monitoring and alarm device provided by this utility model, when the coil of the AC contactor is energized, the first and second normally open contacts of the AC contactor close, and the normally closed contact of the AC contactor opens, thereby energizing and starting the motor in the drive unit. Airflow enters the rodless chamber of the cylinder, pushing the piston outward, which in turn opens the pneumatic knife valve. The coil of the second time relay is energized and starts timing, while the coil of the second intermediate relay is de-energized. When the first detection unit detects that the pneumatic knife valve is open, the coil of the first intermediate relay is energized, the normally open contact of the first intermediate relay closes, the first indicator unit indicates that the pneumatic knife valve is fully open, the first normally closed contact of the first intermediate relay opens, and the second alarm unit does not alarm. When the first detection unit does not detect that the pneumatic knife valve is open, the coil of the first intermediate relay is de-energized, the normally open contact of the first intermediate relay opens, the first indicator unit does not indicate, the first normally closed contact of the first intermediate relay closes, the second time relay finishes timing, the normally open contact of the second time relay closes, and the second alarm unit issues an alarm that the pneumatic knife valve is not fully open.

[0008] When the coil of the AC contactor is de-energized, the first and second normally open contacts of the AC contactor open, and the normally closed contact of the AC contactor closes, causing the motor in the drive unit to stop. Airflow enters the rod chamber of the cylinder, pushing the piston back and closing the pneumatic knife valve. The coil of the second time relay is de-energized, the coil of the second intermediate relay is energized, the first normally open contact of the second intermediate relay closes, and the coil of the first time relay is energized to start timing. When the second detection unit detects the closed state of the pneumatic knife valve, the coil of the third intermediate relay is energized, the normally open contact of the third intermediate relay closes, the second indicating unit indicates that the pneumatic knife valve is fully closed, the first normally closed contact of the third intermediate relay opens, and the first alarm unit does not sound an alarm. When the second detection unit does not detect the closed state of the pneumatic knife valve, the coil of the third intermediate relay is de-energized, the normally open contact of the third intermediate relay opens, the second indicating unit does not indicate, the first normally closed contact of the third intermediate relay closes, the timing of the first time relay ends, the normally open contact of the first time relay closes, and the first alarm unit issues an alarm that the pneumatic knife valve is not fully closed.

[0009] The monitoring and alarm device of this invention can provide indications of the pneumatic knife valve's open / closed position, as well as alarms for incomplete opening and closing. This allows for timely detection of abnormalities, facilitating problem resolution and preventing concentrate contamination and process control issues caused by incomplete closure. When the pneumatic knife valve fails to close properly due to worn sealing rings, insufficient air supply, or slurry blockage, the second detection unit will issue an alarm if it fails to detect the valve's closed state within a preset time. This allows for timely interception of slurry during the shutdown and discharge phase, preventing it from flowing into the concentrate collection box in the gold cleaning chamber and thus avoiding concentrate contamination. The automatic alarm mechanism implemented by the first and second detection units enables operators to quickly locate faults, reducing manual inspection costs.

[0010] Furthermore, the first intermediate relay also has a second normally closed contact, which is connected in series in the branch where the coil of the first intermediate relay is located.

[0011] When the first detection unit detects the open state of the pneumatic knife valve, the coil of the first intermediate relay is energized, the second normally closed contact of the first intermediate relay is opened, the coil of the second intermediate relay is de-energized, the coil of the first time relay is de-energized, and the branch where the first alarm unit is located remains open, thus avoiding false triggering of the alarm for not being fully closed.

[0012] Furthermore, the second intermediate relay also has a second normally open contact, which is connected in parallel across the normally closed contact of the AC contactor.

[0013] When the coil of the AC contactor is de-energized, the normally closed contact of the AC contactor remains closed, the coil of the second intermediate relay is energized, and the second normally open contact of the second intermediate relay closes, realizing the self-locking of the second intermediate relay. This avoids the AC contactor's normally closed contact from malfunctioning and causing the second intermediate relay to lose power, thus ensuring the orderly operation of the circuit.

[0014] Furthermore, the third intermediate relay also has a second normally closed contact, which is connected in series in the branch where the coil of the second time relay is located.

[0015] When the second detection unit detects the closed state of the pneumatic knife valve, the coil of the third intermediate relay is energized, the second normally closed contact of the third intermediate relay is opened, the coil of the second time relay is de-energized, and the branch where the second alarm unit is located remains open, thus avoiding false triggering of the alarm for not being fully opened.

[0016] Furthermore, the first detection unit is a first proximity switch, and the second detection unit is a second proximity switch.

[0017] Non-contact detection of the opening and closing status of pneumatic knife valves is achieved through proximity switches, eliminating mechanical wear, extending equipment lifespan, and making it more adaptable to environments with dust and vibration.

[0018] Furthermore, a first metal support frame is fixedly provided at the right extreme position of the pneumatic knife valve, and a second metal support frame is provided at the left extreme position of the pneumatic knife valve; the first proximity switch is provided on the first metal support frame, and the second proximity switch is provided on the second metal support frame. The right limit position refers to the valve's maximum extension and retraction position when the pneumatic knife valve is fully open; the left limit position refers to the valve's maximum extension and retraction position when the pneumatic knife valve is fully closed.

[0019] Furthermore, the first alarm unit is a first audible and visual alarm or a first voice alarm, and the second alarm unit is a second audible and visual alarm or a second voice alarm.

[0020] Furthermore, the first indicator unit is a first indicator light, and the second indicator unit is a second indicator light.

[0021] Furthermore, a heating element for a thermal relay is also provided on the line between the first normally open contact of the AC contactor and the drive unit.

[0022] Compared with the prior art, the beneficial effects of this utility model are as follows: The monitoring and alarm device provided by this utility model, through the cooperation of the first detection unit, the second detection unit and various relays, can realize the indication of pneumatic knife valve opening position, alarm of not opening position, indication of closing position and alarm of not closing position, so as to promptly detect abnormal problems of not opening or not closing position, so as to facilitate timely detection and resolution of problems and avoid concentrate contamination and process loss caused by not closing position; the dual prompting of the indication unit and the alarm unit facilitates on-site fault diagnosis; the time relay avoids instantaneous false triggering and improves alarm reliability. When the pneumatic knife valve fails to close properly due to wear of the sealing ring, insufficient air supply, or slurry blockage, the second detection unit will not detect the closed state of the pneumatic knife valve within a preset time. The first alarm unit will then issue an alarm. This can promptly intercept the slurry during the shutdown and ore discharge stage, preventing it from flowing into the concentrate collection box in the gold cleaning chamber. This avoids concentrate contamination, thereby preventing the problem of reduced concentrate grade and impact on concentrate sales price caused by concentrate contamination, and improving economic efficiency. Compared to traditional mechanical limit switches that require manual inspection to check for leaks, this utility model achieves an automatic alarm mechanism through the first and second detection units, enabling operators to quickly locate faults, reducing the frequency of manual inspections, reducing manual inspection costs, and reducing the workload of cleaning the metal cleaning room. Attached Figure Description

[0023] To more clearly illustrate the technical solution of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only one embodiment of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a circuit diagram of the monitoring and alarm device for the feed valve in this embodiment of the utility model. Detailed Implementation

[0025] The technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0026] The technical solution of this utility model will be described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0027] The monitoring and alarm device for the feed valve provided in this embodiment of the utility model is used to monitor the opening and closing status of the pneumatic knife valve (i.e., the feed valve) of a centrifugal gravity separation equipment, such as... Figure 1 As shown, the monitoring and alarm device includes an AC contactor, a drive unit for changing the airflow direction, a first intermediate relay, a second intermediate relay, a third intermediate relay, a first time relay, a second time relay, a first detection unit, a second detection unit, a first indication unit, a second indication unit, a first alarm unit, and a second alarm unit. The first normally open contact KM-1 of the AC contactor is used to control the energization or de-energization of the drive unit. The second normally open contact KM-2 of the AC contactor is connected in series with the coil KT2 of the second time relay. The normally closed contact KM-3 of the AC contactor is connected in series with the coil KA2 of the second intermediate relay. The first normally open contact KA2-1 of the second intermediate relay... The coil KT1 of the first time relay is connected in series; the energization of the coil KA1 of the first intermediate relay is controlled by the detection result of the first detection unit; the normally open contact KA1-1 of the first intermediate relay is connected in series with the first indicator unit; the first normally closed contact KA1-2 of the first intermediate relay, the normally open contact KT2-1 of the second time relay, and the second alarm unit are connected in series; the energization of the coil KA3 of the third intermediate relay is controlled by the detection result of the second detection unit; the normally open contact KA3-1 of the third intermediate relay is connected in series with the second indicator unit; the first normally closed contact KA3-2 of the third intermediate relay, the normally open contact KT1-1 of the first time relay, and the first alarm unit are connected in series.

[0028] The drive unit includes a motor, a solenoid valve, and an air pump. The air pump, driven by the motor, provides airflow; for example, it is a reciprocating air compressor. The solenoid valve controls the direction of airflow. When the solenoid valve operates, the air pump provides airflow, and the solenoid valve controls the direction of airflow, thereby driving the actuator (e.g., a cylinder) of the pneumatic knife valve to move the valve core, thus opening or closing the pneumatic knife valve. When the pneumatic knife valve needs to be opened, the motor starts to drive the air pump to provide airflow, energizing the first coil of the solenoid valve. The airflow passes through the solenoid valve into the rodless chamber of the cylinder, pushing the piston out and opening the pneumatic knife valve. When the pneumatic knife valve needs to be closed, the motor stops, energizing the second coil of the solenoid valve. The airflow passes through the solenoid valve into the rod chamber of the cylinder, pushing the piston back and closing the pneumatic knife valve.

[0029] The monitoring and alarm device of this utility model includes valve opening monitoring and valve closing monitoring: During valve opening monitoring, the coil of the AC contactor is energized, the first normally open contact KM-1 and the second normally open contact KM-2 of the AC contactor close, and the normally closed contact KM-3 of the AC contactor opens, which energizes the motor and starts it so that airflow enters the rodless chamber of the cylinder, pushes the piston out, and opens the pneumatic knife valve. The coil KT2 of the second time relay is energized and starts timing, and the coil KA2 of the second intermediate relay is de-energized. When the first detection unit detects the open state of the pneumatic knife valve, the coil KA1 of the first intermediate relay is energized, the normally open contact KA1-1 of the first intermediate relay closes, the first indicator unit indicates that the pneumatic knife valve is fully open, the first normally closed contact KA1-2 of the first intermediate relay opens, and the second alarm unit does not alarm. When the first detection unit does not detect the pneumatic knife valve in the open state, the coil KA1 of the first intermediate relay is de-energized, the normally open contact KA1-1 of the first intermediate relay is opened, the first indicating unit does not indicate, the first normally closed contact KA1-2 of the first intermediate relay is closed, and after the second time relay finishes timing (e.g., timing 10 seconds), the normally open contact KT2-1 of the second time relay is closed, and the second alarm unit issues an alarm that the pneumatic knife valve is not fully open.

[0030] During valve closure monitoring, the coil of the AC contactor is de-energized, the first normally open contact KM-1 and the second normally open contact KM-2 of the AC contactor open, and the normally closed contact KM-3 of the AC contactor closes, causing the motor to stop and allowing airflow to enter the rod chamber of the cylinder, pushing the piston back and closing the pneumatic knife valve. The coil KT2 of the second time relay is de-energized (the branch where the second alarm unit is located is disconnected, so no alarm will be issued for the valve not fully open), the coil KA2 of the second intermediate relay is energized, the first normally open contact KA2-1 of the second intermediate relay closes, and the coil KT1 of the first time relay is energized to start timing. When the second detection unit detects the closed state of the pneumatic knife valve, the coil KA3 of the third intermediate relay is energized, the normally open contact KA3-1 of the third intermediate relay closes, the second indicating unit indicates that the pneumatic knife valve is fully closed, the first normally closed contact KA3-2 of the third intermediate relay opens, and the first alarm unit does not sound an alarm. When the second detection unit does not detect the closed state of the pneumatic knife valve, the coil KA3 of the third intermediate relay is de-energized, the normally open contact KA3-1 of the third intermediate relay is opened, the second indicating unit does not indicate, the first normally closed contact KA3-2 of the third intermediate relay is closed, and after the first time relay finishes timing (e.g., timing 10 seconds), the normally open contact KT1-1 of the first time relay is closed, and the first alarm unit issues an alarm that the pneumatic knife valve is not closed in place.

[0031] In a specific embodiment of this utility model, the first intermediate relay also has a second normally closed contact KA1-3, and the second normally closed contact KA1-3 of the first intermediate relay is connected in series in the branch where the coil KA2 of the second intermediate relay is located.

[0032] When the first detection unit detects the open state of the pneumatic knife valve, the coil KA1 of the first intermediate relay is energized, the second normally closed contact KA1-3 of the first intermediate relay is opened, the coil KA2 of the second intermediate relay is de-energized, the coil KT1 of the first time relay is de-energized, and the branch where the first alarm unit is located remains open, thus avoiding false triggering of the alarm for not being fully closed.

[0033] In a specific embodiment of this utility model, the second intermediate relay also has a second normally open contact KA2-2, which is connected in parallel to the two ends of the normally closed contact KM-3 of the AC contactor.

[0034] When the coil of the AC contactor is de-energized, the normally closed contact KM-3 of the AC contactor remains closed, the coil KA2 of the second intermediate relay is energized, and the second normally open contact KA2-2 of the second intermediate relay closes, realizing the self-locking of the second intermediate relay. This prevents the normally closed contact KM-3 of the AC contactor from malfunctioning and causing the second intermediate relay to lose power, thus ensuring the orderly operation of the circuit.

[0035] In a specific embodiment of this utility model, the third intermediate relay also has a second normally closed contact KA3-3, and the second normally closed contact KA3-3 of the third intermediate relay is connected in series in the branch where the coil KT2 of the second time relay is located.

[0036] When the second detection unit detects the closed state of the pneumatic knife valve, the coil KA3 of the third intermediate relay is energized, the second normally closed contact KA3-3 of the third intermediate relay is opened, the coil KT2 of the second time relay is de-energized, and the branch where the second alarm unit is located remains open, thus avoiding false triggering of the alarm for not being fully opened.

[0037] In a specific embodiment of this utility model, the first detection unit is a first proximity switch SQ1, and the second detection unit is a second proximity switch SQ2.

[0038] The proximity switch detects the position of the pneumatic knife valve's gate using a magnetic strip and magnetic field induction. When the pneumatic knife valve fails to close properly due to worn sealing rings, insufficient air supply, or slurry blockage, and the proximity switch does not detect a signal within a preset time, it triggers the corresponding alarm unit. This allows for timely interception of slurry during the shutdown and discharge phase, preventing it from flowing into the concentrate collection box in the gold cleaning chamber and completely eliminating concentrate contamination. The proximity switch enables non-contact detection of the pneumatic knife valve's opening and closing status, eliminating mechanical wear and extending its lifespan from 3 months to over 3 years, thus improving equipment lifespan. The non-contact detection of the proximity switch is more adaptable to environments with dust and vibration. With an IP67 / IP68 protection rating, it can withstand dust, slurry splashes, and temperature fluctuations of -25℃ to +70℃ in the concentrator, significantly reducing the false alarm rate. The rapid response of the proximity switch shortens the pneumatic knife valve fault handling time, greatly improving the effective operating rate of the equipment, extending its service life, reducing equipment failure rate and maintenance costs, improving production efficiency, and preventing safety accidents, bringing significant economic and safety benefits to the enterprise.

[0039] In a specific embodiment of this utility model, a first metal support frame is fixedly provided at the right extreme position of the pneumatic knife valve, and a second metal support frame is provided at the left extreme position of the pneumatic knife valve; a first proximity switch SQ1 is provided on the first metal support frame, and a second proximity switch is provided on the second metal support frame; wherein, the right extreme position refers to the valve extension and retraction limit position (i.e., the piston extension limit position) when the pneumatic knife valve is fully open; the left extreme position refers to the valve extension and retraction limit position (i.e., the piston retraction limit position) when the pneumatic knife valve is fully closed.

[0040] The first proximity switch SQ1 and the second proximity switch SQ2 are installed at the right limit position and the left limit position of the pneumatic knife valve, respectively, to ensure that the signal can be reliably triggered when the pneumatic knife valve is fully open or fully closed; the first proximity switch SQ1 and the second proximity switch SQ2 are mounted on a metal support frame to ensure stability and prevent interference with the moving parts of the pneumatic knife valve.

[0041] In a specific embodiment of this utility model, the first alarm unit is a first audible and visual alarm HA1 or a first voice alarm, and the second alarm unit is a second audible and visual alarm HA2 or a second voice alarm.

[0042] In a specific embodiment of this utility model, the first indicator unit is a first indicator light HR, and the second indicator unit is a second indicator light HG.

[0043] In a specific embodiment of this utility model, a heating element FR of a thermal relay is also provided on the line between the first normally open contact KM-1 of the AC contactor and the drive unit. The thermal relay avoids damage to the drive unit caused by overload or phase loss fault.

[0044] In a specific embodiment of this utility model, a main circuit breaker QF1 is also provided on the power supply line of the motor.

[0045] This invention achieves intelligent detection of the opening and closing status of the pneumatic knife valve in a centrifugal reselection device through the cooperation of the first detection unit, the second detection unit, and various relays. This solves the reliability problem of traditional valve control and ensures the efficient and stable operation of the reselection process.

[0046] The above description only discloses specific embodiments of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or modifications that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model.

Claims

1. A monitoring and alarm device for a feed valve, used to monitor the opening and closing status of a pneumatic knife valve in a centrifugal gravity separator, characterized in that, The monitoring and alarm device includes an AC contactor, a drive unit for driving the pneumatic knife valve to open or close, a first intermediate relay, a second intermediate relay, a third intermediate relay, a first time relay, a second time relay, a first detection unit, a second detection unit, a first indication unit, a second indication unit, a first alarm unit, and a second alarm unit. The first normally open contact of the AC contactor is used to control the energization or de-energization of the drive unit. The second normally open contact of the AC contactor is connected in series with the coil of the second time relay, and the normally closed contact of the AC contactor is connected in series with the coil of the second intermediate relay. The first normally open contact of the second intermediate relay is connected in series with the coil of the first time relay. The energization or de-energization of the coil of the first intermediate relay is controlled by the detection result of the first detection unit. The normally open contact of the first intermediate relay is connected in series with the first indicator unit. The first normally closed contact of the first intermediate relay, the normally open contact of the second time relay, and the second alarm unit are connected in series. The energization or de-energization of the coil of the third intermediate relay is controlled by the detection result of the second detection unit. The normally open contact of the third intermediate relay is connected in series with the second indicator unit. The first normally closed contact of the third intermediate relay, the normally open contact of the first time relay, and the first alarm unit are connected in series.

2. The monitoring and alarm device for the feed valve according to claim 1, characterized in that, The first intermediate relay also has a second normally closed contact, which is connected in series in the branch where the coil of the first intermediate relay is located.

3. The monitoring and alarm device for the feed valve according to claim 1, characterized in that, The second intermediate relay also has a second normally open contact, which is connected in parallel across the normally closed contact of the AC contactor.

4. The monitoring and alarm device for the feed valve according to claim 1, characterized in that, The third intermediate relay also has a second normally closed contact, which is connected in series in the branch where the coil of the second time relay is located.

5. The monitoring and alarm device for the feed valve according to claim 1, characterized in that, The first detection unit is a first proximity switch, and the second detection unit is a second proximity switch.

6. The monitoring and alarm device for the feed valve according to claim 5, characterized in that, A first metal support frame is fixedly provided at the right extreme position of the pneumatic knife valve, and a second metal support frame is provided at the left extreme position of the pneumatic knife valve; the first proximity switch is provided on the first metal support frame, and the second proximity switch is provided on the second metal support frame. The right limit position refers to the valve's maximum extension and retraction position when the pneumatic knife valve is fully open; the left limit position refers to the valve's maximum extension and retraction position when the pneumatic knife valve is fully closed.

7. The monitoring and alarm device for the feed valve according to claim 1, characterized in that, The first alarm unit is a first audible and visual alarm or a first voice alarm, and the second alarm unit is a second audible and visual alarm or a second voice alarm.

8. The monitoring and alarm device for the feed valve according to claim 1, characterized in that, The first indicator unit is a first indicator light, and the second indicator unit is a second indicator light.

9. The monitoring and alarm device for the feed valve according to any one of claims 1 to 8, characterized in that, A heating element of a thermal relay is also provided on the line between the first normally open contact of the AC contactor and the drive unit.

Images