Device capable of preventing power failure alarm of connecting plug

Abstract

The invention discloses an alarm device capable of preventing power failure of a connecting plug, which comprises a temperature sensor, an alarm and a control unit, and is characterized in that the control unit is respectively connected with the temperature sensor and the alarm so as to control the alarm to give an alarm when the real-time temperature detected by the temperature sensor exceeds a preset threshold value; the temperature sensor specifically comprises a temperature-sensitive resistor electrically connected in the circuit module, a resistance detection unit for analyzing the instant resistance value of the temperature-sensitive resistor by monitoring the current and voltage in the circuit module, and an analysis module for converting the instant resistance value into the instant temperature; the analysis module is connected with the control unit and sends the instant temperature to the control unit, and the temperature sensitive resistor is arranged in the motor and forms real-time heat conduction with a heating part of the motor. When the connecting plug is disconnected, the resistance value of the equivalent resistor replaces the instant resistance value of the temperature-sensitive resistor to be input into the control unit, an alarm is prevented from being triggered, and therefore a worker does not need to go to the frequency converter for resetting operation, and a large amount of time and labor cost are saved.

Description

Technical Field

[0001] The invention relates to the technical field of motor temperature control equipment, and in particular to a device capable of preventing a plug connector from generating a power-off alarm. Background Art

[0002] In the process of producing liquid crystal substrate glass, the prepared powder is generally put into the pool furnace, and then the powder is turned into glass liquid at a certain temperature through the electric and gas heating methods of the pool furnace. The glass liquid then flows to the next process to form sheets of liquid crystal substrate glass. The process of putting powder into the pool furnace requires manual use of a crane to first add the powder in the ton bag from the feeding port to the large silo of the feeding system. The feeding system then adds the powder in the large silo to the pool furnace through a spiral dragon conveyor. The feeder consists of a main motor, a gearbox, a chain, a bearing seat, a spiral shaft, a barrel water cooling system, a circular feeding barrel, a feeder main frame, an electrical control box, etc. The motor rotation is controlled by a frequency converter, and the frequency converter is installed in the control cabinet of the feeder. The distance between the feeder and the frequency converter is far, and the feeder needs to be replaced regularly.

[0003] The ambient temperature at the location of the feeder is relatively high, so there will be a problem. The feeder needs to be replaced regularly. When replacing, the plug connector must be unplugged. The feedback signal of the motor temperature received by the inverter will be disconnected, and the resistance value will become infinite. At this time, the inverter thinks that the motor temperature is too high and an alarm will sound. If the alarm information of the inverter is not reset after replacing the feeder, the feeder motor will not start running. Therefore, someone needs to reset the inverter at a distant feeder control cabinet. There will also be problems such as people running back and forth to operate or operating through intercoms and operators not being able to reset the inverter smoothly due to unfamiliarity with the process and methods. These will delay the normal pool furnace feeding process after replacing the feeder. In addition, since the feeder is located at the front end of the pool furnace, the ambient temperature around the feeder is very high, and the motor is running for a long time. In order to ensure the normal operation of the feeder, it is absolutely not allowed to modify the settings on the inverter to cancel the motor temperature alarm in order to avoid the reset operation of the inverter alarm. Summary of the invention

[0004] In order to solve the technical problems existing in the background technology, the present invention provides a device capable of preventing the power-off alarm of the plug connector.

[0005] The present invention proposes a device capable of preventing a plug connector from being powered off and alarming, comprising: a temperature sensor, an alarm, and a control unit. The control unit is respectively connected to the temperature sensor and the alarm to control the alarm to alarm when the real-time temperature detected by the temperature sensor exceeds a preset threshold value. The temperature sensor specifically comprises: a thermistor electrically connected to a circuit module, a resistance detection unit that analyzes the instantaneous resistance value of the thermistor by monitoring the current and voltage in the circuit module, and an analysis module for converting the instantaneous resistance value into an instantaneous temperature. The analysis module is connected to the control unit and sends the instantaneous temperature to the control unit. The thermistor is built into a motor and forms real-time heat conduction with the heating components of the motor. The alarm , the control unit and the resistance detection unit are powered by a second power supply other than the first power supply, the circuit module includes a first circuit unit connected in series with a thermistor, the plug connector between the motor and the first power supply is installed in the first circuit unit, the circuit module is powered by the first power supply that powers the motor, the motor alarm device also includes a switching mechanism, the circuit module also includes a second circuit unit, the switching mechanism is installed between the first circuit unit and the second circuit unit, when the plug connector is turned on to enable the first power supply to power the motor, the switching mechanism turns on the first circuit unit and disconnects the second circuit unit, when the plug connector is disconnected and the first power supply stops powering the motor, the switching mechanism turns on the second circuit unit and disconnects the first circuit unit.

[0006] Preferably, the switching mechanism comprises a single-pole double-throw switch, the fixed end of the single-pole double-throw switch is connected to the thermistor, and when the plug connector is turned on to allow the first power supply to power the motor, the moving end of the single-pole double-throw switch is connected to the first circuit unit.

[0007] Preferably, when the plug connector is disconnected and the first power supply stops supplying power to the motor, the moving end of the single-pole double-throw switch is connected to the second circuit unit.

[0008] Preferably, when the plug connector is turned on to enable the first power supply to power the motor, the switching mechanism turns on the first circuit unit and disconnects the second circuit unit, the fixed end of the single-pole double-throw switch is connected to the thermistor, and the moving end of the single-pole double-throw switch is connected to the first circuit unit. The thermistor and the heat-generating components of the motor form real-time heat conduction, and the analysis module analyzes the instantaneous resistance value of the thermistor and sends the instantaneous temperature to the control unit.

[0009] Preferably, when the plug connector is disconnected and the first power supply stops supplying power to the motor, the switching mechanism turns on the second circuit unit and disconnects the first circuit unit, the fixed end of the single-pole double-throw switch is connected to the thermistor, and the moving end of the single-pole double-throw switch is connected to the second circuit unit. The second circuit unit includes an equivalent resistor. After the plug connector is disconnected, the instantaneous resistance value of the thermistor is replaced by the resistance value of the equivalent resistor, connected to the analysis module and input into the control unit to avoid triggering the alarm.

[0010] Preferably, the alarm and the control unit are integrated in a frequency converter connected to the motor.

[0011] Preferably, the first power supply adopts a 220V AC power supply.

[0012] Preferably, the second power supply is a 24V DC power supply.

[0013] The device proposed by the present invention can prevent the plug connector from being powered off. The advantages are: through the design of the switching mechanism and the equivalent resistor, when the plug connector is disconnected, the equivalent resistor value is used to replace the instantaneous resistance value of the temperature-sensitive resistor and input into the control unit, which effectively avoids triggering the alarm, so there is no need to manually go to the inverter to perform the reset operation, saving a lot of time and labor costs. The temperature-sensitive resistor in the temperature sensor conducts heat with the heating component of the motor in real time. Combined with the resistance detection unit and the analysis module, it can accurately sense the temperature change of the motor and send the instantaneous temperature to the control unit to ensure effective monitoring of the motor temperature. The alarm, control unit and resistance detection unit are powered by an independent second power supply, which reduces the impact of factors such as the fluctuation of the first power supply on the operation of the device, and ensures the stability and reliability of the operation of the device. The alarm and the control unit are integrated in the inverter, making the overall structure of the device compact and easy to install and maintain. At the same time, the inverter resources are better utilized to achieve accurate monitoring and intelligent control of the motor temperature, improve the efficiency and convenience of production operations, and effectively ensure the efficient and stable operation of modern factories. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A schematic diagram of a switching mechanism connected to a first circuit unit of a device capable of preventing a plug connector from being powered off and alarming according to the present invention;

[0015] Figure 2 A schematic diagram of connecting a switching mechanism of a device capable of preventing a plug connector from generating a power failure alarm proposed by the present invention to a second circuit unit. DETAILED DESCRIPTION

[0016] refer to Figure 1-2 The present invention proposes a device capable of preventing the plug connector from being powered off.

[0017] In the automation control system of modern factories, PLC control is widely used. The distance between the input and output elements of the PLC control cabinet and the actual control actuator varies, some are close and some are far. Among them, the rotating motor is a type of output element of the actual control actuator of the PLC, and its precise control depends on the frequency converter. To ensure the safe operation of the motor, the frequency converter is equipped with a motor operating temperature feedback signal input mechanism. When the motor exceeds the preset limit operating temperature of the frequency converter due to overload, long-term high temperature environment and poor heat dissipation, the frequency converter will issue an alarm signal and force the motor to stop running to protect the motor from burning.

[0018] However, there is a significant problem for actuators that need to be replaced regularly and have multi-point connection plugs. Once the plug is unplugged, the signal line between the motor temperature thermistor and the inverter connected through the plug is immediately disconnected. At this time, the current motor temperature signal received by the inverter is no longer the original value, but presents an infinite resistance state. Based on this, the inverter will immediately determine that the motor temperature is too high and issue an alarm. Even after the actuator is replaced, the plug is re-plugged, and the signal between the motor temperature thermistor and the inverter returns to normal, if the actuator motor is to resume normal operation, a reset operation must still be performed on the inverter to eliminate the alarm. Especially when the inverter is far away from the motor, every time the actuator is replaced, personnel have to be arranged to go to the inverter to perform manual alarm reset operations, which undoubtedly consumes a lot of time and labor costs.

[0019] The invention aims to design a device that can prevent the plug connector from powering off and alarming, which can effectively solve the above problems. The device mainly includes a temperature sensor, an alarm and a control unit. The control unit is connected to the temperature sensor and the alarm respectively, and its function is to control the alarm to sound an alarm when the real-time temperature detected by the temperature sensor exceeds the preset threshold.

[0020] The temperature sensor includes a thermistor electrically connected to the circuit module. The thermistor is built into the motor and forms real-time heat conduction with the motor's heating components, which can accurately sense the temperature changes of the motor. At the same time, the temperature sensor is also equipped with a resistance detection unit, which analyzes the instantaneous resistance value of the thermistor by monitoring the current and voltage in the circuit module. In addition, there is an analysis module, which is responsible for converting the instantaneous resistance value into the instantaneous temperature, and then sending the instantaneous temperature to the control unit.

[0021] It is worth noting that the alarm, control unit and resistance detection unit are not powered by the first power supply for the motor, but by an independent second power supply. The first power supply uses a 220V AC power supply, the second power supply uses a 24V DC power supply, the circuit module includes a first circuit unit connected in series with the temperature-sensitive resistor, and the plug connector between the motor and the first power supply is installed in the first circuit unit, and the circuit module is powered by the first power supply.

[0022] In order to further optimize the performance of the device, the motor alarm device is also specially provided with a switching mechanism. In addition to the first circuit unit, the circuit module is also provided with a second circuit unit. The switching mechanism is installed between the first circuit unit and the second circuit unit, and it can perform intelligent switching according to the state of the plug connector. Specifically, when the plug connector is turned on, so that the first power supply can supply power to the motor, the switching mechanism turns on the first circuit unit and disconnects the second circuit unit. At this time, the single-pole double-throw switch is a preferred form of the switching mechanism, and its fixed end is connected to the thermistor, and the moving end is connected to the first circuit unit. The thermistor and the heating components of the motor continue to maintain real-time heat conduction, and the analysis module normally analyzes the instantaneous resistance value of the thermistor and sends the instantaneous temperature to the control unit.

[0023] When the plug connector is disconnected and the first power supply stops supplying power to the motor, the switching mechanism will react quickly, turning on the second circuit unit and disconnecting the first circuit unit. In this case, the fixed end of the single-pole double-throw switch is still connected to the thermistor, but the moving end is connected to the second circuit unit. An equivalent resistor is set in the second circuit unit. After the plug connector is disconnected, the resistance value of the equivalent resistor will replace the instantaneous resistance value of the thermistor and be connected to the analysis module and input into the control unit. Through this ingenious design, the alarm can be effectively avoided from being triggered, and there is no need for manual reset operation.

[0024] In actual application scenarios, the alarm and control unit are usually integrated into the inverter connected to the motor. Such an integrated design not only makes the overall structure of the device more compact and easy to install and maintain, but also makes better use of the existing resources and functions of the inverter to achieve accurate monitoring and intelligent control of the motor temperature, greatly improving the efficiency and convenience of production operations, and providing a strong guarantee for the efficient and stable operation of modern factories.

[0025] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and the inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A device capable of preventing a plug connector from being powered off, characterized in that: include: A temperature sensor, an alarm, and a control unit. The control unit is respectively connected to the temperature sensor and the alarm to control the alarm to alarm when the real-time temperature detected by the temperature sensor exceeds a preset threshold. The temperature sensor specifically includes: a thermistor electrically connected to a circuit module, a resistance detection unit that analyzes the instantaneous resistance value of the thermistor by monitoring the current and voltage in the circuit module, and an analysis module for converting the instantaneous resistance value into an instantaneous temperature. The analysis module is connected to the control unit and sends the instantaneous temperature to the control unit. The thermistor is built into the motor and forms real-time heat conduction with the heating component of the motor. The alarm, the control unit, and the resistance detection unit are powered by a second power supply other than the first power supply. The circuit module includes a first circuit unit connected in series with the thermistor. The plug connector between the motor and the first power supply is installed in the first circuit unit. The circuit module is powered by the first power supply that powers the motor. The motor alarm device also includes a switching mechanism. The circuit module also includes a second circuit unit. The switching mechanism is installed between the first circuit unit and the second circuit unit. When the plug connector is turned on so that the first power supply powers the motor, the switching mechanism turns on the first circuit unit and disconnects the second circuit unit. When the plug connector is disconnected and the first power supply stops powering the motor, the switching mechanism turns on the second circuit unit and disconnects the first circuit unit.

2. A device capable of preventing a plug connector from being powered off according to claim 1, characterized in that: The switching mechanism includes a single-pole double-throw switch, the fixed end of the single-pole double-throw switch is connected to the temperature-sensitive resistor, and when the plug connector is turned on to enable the first power supply to power the motor, the moving end of the single-pole double-throw switch is connected to the first circuit unit.

3. A device capable of preventing a plug connector from being powered off according to claim 2, characterized in that: When the plug connector is disconnected and the first power supply stops supplying power to the motor, the moving end of the single-pole double-throw switch is connected to the second circuit unit.

4. A device capable of preventing a plug connector from being powered off according to claim 3, characterized in that: When the plug connector is turned on to enable the first power supply to supply power to the motor, the switching mechanism turns on the first circuit unit and disconnects the second circuit unit, the fixed end of the single-pole double-throw switch is connected to the thermistor, and the moving end of the single-pole double-throw switch is connected to the first circuit unit. The thermistor and the heating components of the motor form real-time heat conduction, and the analysis module analyzes the instantaneous resistance value of the thermistor and sends the instantaneous temperature to the control unit.

5. A device capable of preventing a plug connector from being powered off according to claim 4, characterized in that: When the plug connector is disconnected and the first power supply stops supplying power to the motor, the switching mechanism turns on the second circuit unit and disconnects the first circuit unit, the fixed end of the single-pole double-throw switch is connected to the thermistor, and the moving end of the single-pole double-throw switch is connected to the second circuit unit. The second circuit unit includes an equivalent resistor. After the plug connector is disconnected, the instantaneous resistance value of the thermistor is replaced by the resistance value of the equivalent resistor, connected to the analysis module and input into the control unit to avoid triggering the alarm.

6. A device capable of preventing a plug connector from being powered off according to claim 1, characterized in that: The alarm and control unit are integrated in the frequency converter connected to the motor.

7. A device capable of preventing a plug connector from being powered off according to claim 1, characterized in that: The first power supply adopts 220V AC power supply.

8. A device capable of preventing a plug connector from being powered off according to claim 1, characterized in that: The second power supply adopts 24V DC power supply.

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