Control and protection device and system for heat treatment electric furnace

Abstract

The invention discloses a heat treatment electric furnace control protection device and system, and relates to the field of electric furnace control. The system comprises a local control unit, a remote wireless remote control unit and a safety interlocking unit, the local control unit comprises a furnace door lifting execution and sudden stop protection circuit; the remote wireless remote control unit remotely controls sudden stop and lifting of the furnace door through wireless signals; the safety interlocking unit monitors the forklift operation state and the furnace door state signal and automatically triggers a protection instruction according to safety logic. According to the system, the risk that the furnace door is not opened due to collision of the forklift caused by separation of the furnace body and the forklift control system is effectively solved, equipment damage accidents caused by furnace door limiting failure are prevented through torque monitoring and automatic sudden stop, and an operator can perform emergency operation without danger crossing a dangerous area by means of a remote control function; the personal safety hidden danger is fundamentally eliminated, and the intrinsic safety and the operation convenience of the system are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of electric furnace control, and in particular to a control and protection device and system for a heat treatment electric furnace. Background Technology

[0002] Heat treatment furnace systems are key equipment in industrial production, typically consisting of the furnace body, mobile water tankers, and loading / unloading forklifts. In existing technologies, the control systems of such systems generally employ a separate design, meaning the furnace door lifting control system and the loading / unloading forklift's operation control system are independent and located in two separate places. Their control core often relies on traditional relay-contactor logic circuits or basic PLC programs, providing basic local button operation, limit switch protection, and overload protection functions. In terms of operation, it usually requires a worker to operate the system locally near the furnace control cabinet or to monitor it on-site when the system is running automatically.

[0003] However, this traditional separate control system exposes significant safety hazards and operational inconveniences in practical applications. Firstly, due to the lack of a direct and reliable safety interlock between the furnace body and the forklift control system, if the furnace door fails to open normally due to a malfunction or signal delay when the forklift is in automatic operation mode, the forklift will continue to move according to the program, posing a significant risk of directly impacting the closed furnace door and easily causing equipment damage. Secondly, the mechanical limit switches on which the furnace door lifting mechanism relies are prone to failure. Once the upper limit switch malfunctions, the furnace door will continue to rise, potentially leading to serious mechanical failures such as deformation of the lifting mechanism, overload and breakage of the wire rope, or detachment of the counterweight, posing a personal safety threat to on-site personnel. Finally, when communication between systems becomes unstable or other abnormal conditions occur, operators are forced to cross the forklift support, which is only about 30 centimeters wide and has a 5-meter-deep water tank below, to risk reaching the furnace control cabinet for emergency operations; this emergency route itself constitutes a very high personal safety hazard. To address these issues, this invention provides a heat treatment electric furnace control and protection device and system to solve the aforementioned problems. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a control and protection device and system for a heat treatment electric furnace. This solves several problems encountered in actual use. For example, when the furnace body control system and forklift control system are located in separate parts, issues arise such as: if the furnace door is not opened when the forklift is in automatic mode, it may collide with the furnace door; when the upper limit control of the furnace door fails, the door will continue to rise and fall, leading to deformation of the furnace door lifting device and excessive stress on its components, causing parts to detach and posing personal injury and equipment malfunction risks to operators; and when system communication is unstable, operators have to operate the furnace body control system through a forklift support only 30 centimeters wide and a 5-meter-deep pool of water, posing a significant safety hazard to the operator.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a heat treatment electric furnace control and protection device, comprising a heat treatment electric furnace control box, wherein a cabinet door is rotatably connected to the front end of the heat treatment electric furnace control box, and a control button and a heat dissipation groove are installed on the cabinet door. The control button is used to control the raising and lowering of the electric furnace door, and the heat dissipation groove is used to dissipate heat from the circuit board and electrical components inside the heat treatment electric furnace control box. A knockout hole is provided at the bottom end of the heat treatment electric furnace control box for a data cable to pass through. A signal transmission unit is fixedly connected to the side end of the heat treatment electric furnace control box, and the signal transmission unit is used to receive and transmit signals.

[0006] Preferably, the system of this heat treatment electric furnace control and protection device includes: a local control unit, a remote wireless control unit, and a safety interlock unit;

[0007] The local control unit is located inside the heat treatment furnace control box, and includes an execution circuit for controlling the raising and lowering of the furnace door and an emergency stop protection circuit.

[0008] The remote wireless control unit includes a handheld remote controller and a signal transmission unit. The signal transmission unit is electrically connected to the local control unit. The signal transmission unit is used to receive wireless signals emitted by the remote controller and generate corresponding control commands.

[0009] The safety interlock unit is signal-connected to the signal transmission unit;

[0010] The remote wireless remote control unit can remotely trigger the emergency stop protection circuit in the local control unit to realize the emergency shutdown of the system; in addition, the remote wireless remote control unit can remotely simulate local operation signals to directly control the operation of the furnace door lifting and lowering actuator circuit.

[0011] The safety interlock unit is used to monitor signals representing the forklift's operating status and the furnace door status signals. Based on preset safety logic, when a collision or equipment damage risk is detected, it automatically sends a control command to the local control unit to forcibly interrupt unsafe operations.

[0012] Preferably, the remote wireless control unit controls the emergency stop protection circuit in the following way:

[0013] The receiver controls the coil circuit of an emergency stop intermediate relay;

[0014] The normally closed contact of the emergency stop intermediate relay is connected in series in the main control power circuit of the local control unit;

[0015] When an emergency stop command is issued via the remote control, the emergency stop intermediate relay is de-energized, its normally closed contact opens, thereby cutting off the power supply to the entire control circuit.

[0016] Preferably, the remote wireless control unit controls the furnace door lifting and lowering actuator circuit in the following way:

[0017] The signal transmission unit outputs furnace door raising and lowering commands, which are connected in parallel to the two ends of the locally controlled raising and lowering buttons, respectively.

[0018] When an up or down command is issued via the remote control, it is equivalent to remotely triggering the local up or down button, thereby driving the corresponding up or down contactor to operate.

[0019] Preferably, the safety interlock unit includes a proximity monitoring module and a logic control module;

[0020] The proximity monitoring module is used to detect whether the forklift has entered the preset safe area in front of the furnace door. The forklift is equipped with a signal transmitter or positioning tag for identification.

[0021] The logic control module is configured to: when a forklift is detected entering the detection area, immediately query the furnace door status; if the furnace door is not fully open, issue an emergency stop command to the local control unit to force the forklift automatic control system to stop.

[0022] Preferably, the forklift proximity monitoring module uses one of the following: a UWB positioning sensor, an RFID area detection sensor, or a laser ranging sensor, and the signal transmitter or positioning tag on the forklift is a matching UWB tag, RFID tag, or laser reflector.

[0023] Preferably, the safety interlock unit includes a torque monitoring module;

[0024] The torque monitoring module is used to monitor the operating current of the furnace door lifting motor or the force on the transmission mechanism in real time.

[0025] When the detected current or pressure value exceeds the preset safety threshold, it is determined that the furnace door is operating abnormally, and an instruction is immediately sent to the local control unit to cut off the power supply to the furnace door lifting motor.

[0026] Preferably, the operating modes of the system include:

[0027] Local manual mode: Controlled via the control buttons on the heat treatment furnace control box;

[0028] Remote manual mode: Controlled via the remote wireless remote control unit, the operator can perform emergency stops and furnace door operations from a safe position;

[0029] Automatic interlock mode: The safety interlock unit is in an active state and automatically performs safety monitoring and protection.

[0030] The technical effects and advantages of this invention are as follows:

[0031] 1. This heat treatment electric furnace control and protection device and system effectively prevent equipment collisions and improve system linkage safety. By adding a safety interlock unit, the position of the forklift and the status of the furnace door are monitored in real time, establishing a mandatory safety logic. When the system detects that the forklift has entered the working area and the furnace door is not open, it can automatically interrupt the forklift operation program, fundamentally eliminating the accident of the forklift hitting the furnace door and solving the linkage safety problem caused by the separation of the control system.

[0032] 2. This type of heat treatment electric furnace control and protection device and system enhances the protection of the equipment itself and prevents the escalation of faults; the torque monitoring module monitors the current of the furnace door lifting motor or the force on the mechanism in real time, providing secondary soft protection for the furnace door lifting in addition to mechanical limit; once an abnormal overload is detected, the system can immediately and automatically cut off the power supply, effectively preventing secondary accidents such as deformation of the lifting mechanism and damage to components, and ensuring the inherent safety of the equipment.

[0033] 3. This type of heat treatment electric furnace control and protection device and system fundamentally improves operational safety and enables remote emergency operation. Through the remote wireless remote control unit, the operator can conveniently control the lifting and lowering of the furnace door and the emergency shutdown of the system within a safe area. This completely eliminates the personal safety threat to the operator who has to risk crossing dangerous areas to perform local operations when the system malfunctions, changing the emergency response method from "danger nearby" to "remote safety", greatly improving the safety factor of the job. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a system framework diagram of the present invention;

[0036] Figure 2 This is a flowchart illustrating the conventional remote control operation process of the present invention.

[0037] Figure 3 This is a flow chart of the furnace door-forklift process of the present invention;

[0038] Figure 4 This is a circuit diagram of the remote control system of the present invention;

[0039] Figure 5 This is a schematic diagram of the overall front structure of the present invention;

[0040] Figure 6 This is a schematic diagram of the overall bottom structure of the present invention.

[0041] In the diagram: 1. Heat treatment furnace control box; 11. Cabinet door; 12. Control button; 13. Heat dissipation slot; 14. Knockout hole; 15. Signal transmission unit. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0044] This invention discloses a control and protection device and system for a heat treatment electric furnace, according to the appendix. Figures 5 to 6 As shown, the device includes a heat treatment furnace control box 1. A cabinet door 11 is rotatably connected to the front end of the heat treatment furnace control box 1. A control button 12 and a heat dissipation slot 13 are installed on the cabinet door 11. The control button 12 is used to control the raising and lowering of the furnace door. The heat dissipation slot 13 is used to dissipate heat from the circuit board and electrical components inside the heat treatment furnace control box 1. A knockout hole 14 is provided at the bottom of the heat treatment furnace control box 1 for passing through a data cable. A signal transmission unit 15 is fixedly connected to the side of the heat treatment furnace control box 1 for receiving and transmitting signals.

[0045] According to the appendix Figures 1 to 4 As shown, the system further includes: a local control unit, a remote wireless control unit, and a safety interlock unit;

[0046] The local control unit is located in the heat treatment furnace control box 1. The local control unit includes an execution circuit for controlling the lifting and lowering of the furnace door and an emergency stop protection circuit.

[0047] The remote wireless control unit includes a handheld remote controller and a signal transmission unit 15. The signal transmission unit 15 is electrically connected to the local control unit. The signal transmission unit 15 is used to receive the wireless signal emitted by the remote controller and generate corresponding control commands.

[0048] The safety interlock unit is connected to the signal transmission unit 15 via a signal connection.

[0049] Among them, the remote wireless remote control unit can remotely trigger the emergency stop protection circuit in the local control unit to realize the emergency shutdown of the system; in addition, the remote wireless remote control unit can remotely simulate local operation signals to directly control the action of the furnace door lifting and lowering execution circuit.

[0050] The safety interlock unit is used to monitor signals that characterize the forklift's operating status and the furnace door status signals. Based on preset safety logic, when it determines that there is a risk of collision or equipment damage, it automatically sends a control command to the local control unit to forcibly interrupt unsafe operations.

[0051] In this embodiment, the local control unit is specifically as follows:

[0052] 1. Power supply and protection section: L and N are the power phase line and neutral line, respectively. FU1 and FU2 are fuses, which provide short circuit protection. When a short circuit fault occurs in the circuit, the fuses blow, cutting off the circuit and protecting the electrical equipment.

[0053] 2. Emergency stop control section: The "remote emergency stop" button is connected in series with the intermediate relay KA coil. When the emergency stop button is pressed, the KA coil is de-energized, and its normally closed contact opens, which can cut off the entire control circuit, realize emergency stop, and ensure the safety of equipment and personnel.

[0054] 3. Furnace System Control Section:

[0055] Lifting Control: SB1 is the lifting button, and KM1 is the lifting contactor. Pressing SB1 energizes the KM1 coil, closing its main contacts and controlling the corresponding motor or actuator to rotate forward, thus lifting the furnace system. The normally closed contact of KM2 is an interlock contact to prevent KM1 and KM2 from being energized simultaneously, avoiding short circuits caused by simultaneous forward and reverse motor operation. SQ2 is the lifting limit switch. When the furnace system reaches its limit position, SQ2 activates, opening its normally closed contact, de-energizing the KM1 coil, and stopping the lifting, thus providing limit protection and preventing damage to the equipment due to excessive lifting. HL1 is the lifting status indicator light. When the KM1 coil is energized, HL1 illuminates, indicating that the furnace system is in the lifting state.

[0056] Lowering control: SB2 is the lowering button, and KM2 is the lowering contactor. Pressing SB2 energizes the KM2 coil, closing its main contacts and controlling the corresponding motor or actuator to reverse, thus lowering the furnace system. The normally closed contact of KM1 is an interlock contact. SQ1 is the lowering limit switch, providing lowering limit protection. HL2 is the lowering status indicator light; when the KM2 coil is energized, HL2 lights up, indicating that the furnace system is in the lowering state.

[0057] Furnace System 2 Control Section: Similar to Furnace System 1 Control Logic. SB3 is the up button, KM3 is the up contactor; SB4 is the down button, KM4 is the down contactor; SQ3 is the up limit switch for Furnace System 2, SQ4 is the down limit switch; HL3 is the up status indicator light for Furnace System 2, HL4 is the down status indicator light; there is an interlock contact between KM4 and KM3; FR2 is an overload protection thermal relay. When related motors or other equipment in Furnace System 2 are overloaded, FR2 activates, its normally closed contact opens, cutting off the control circuit and achieving overload protection.

[0058] According to the appendix Figure 4 As shown, the remote wireless control unit further controls the emergency stop protection circuit in the following way:

[0059] The receiver controls the coil circuit of an emergency stop intermediate relay;

[0060] The normally closed contact of the emergency stop intermediate relay is connected in series in the main control power circuit of the local control unit;

[0061] When an emergency stop command is issued via remote control, the emergency stop intermediate relay is de-energized, its normally closed contact opens, thereby cutting off the power supply to the entire control circuit.

[0062] According to the appendix Figure 2 and Figure 4 As shown, the remote wireless control unit controls the furnace door lifting actuator circuit in the following way:

[0063] The signal transmission unit 15 outputs furnace door raising and lowering commands, which are connected in parallel to the two ends of the locally controlled raising and lowering buttons, respectively;

[0064] When an up or down command is issued via remote control, it is equivalent to remotely triggering the local up or down button, thereby driving the corresponding up or down contactor to operate.

[0065] According to the appendix Figure 1 and Figure 3 As shown, the safety interlock unit specifically discloses that it includes a proximity monitoring module and a logic control module;

[0066] The proximity monitoring module is used to detect whether the forklift has entered the preset safe area in front of the furnace door. The forklift is equipped with a signal transmitter or positioning tag for identification.

[0067] The logic control module is configured to: when a forklift is detected entering the detection area, immediately check the furnace door status; if the furnace door is not fully open, send an emergency stop command to the local control unit to force the forklift automatic control system to stop.

[0068] The forklift proximity monitoring module uses one of the following: a UWB positioning sensor, an RFID area detection sensor, or a laser ranging sensor. The signal transmitter or positioning tag on the forklift is a matching UWB tag, RFID tag, or laser reflector.

[0069] In this embodiment, when the proximity monitoring module detects that the forklift has entered the preset detection area, the logic control module will immediately check the furnace door status signal; if the furnace door is not open, it is determined that there is a risk of collision, and the control module will automatically send an emergency stop command to the control system to force the forklift to stop.

[0070] According to the appendix Figure 1 As shown, it is particularly important to emphasize that the safety interlock unit includes a torque monitoring module;

[0071] The torque monitoring module is used to monitor the operating current of the furnace door lifting motor or the force on the transmission mechanism in real time.

[0072] When the detected current or pressure value exceeds the preset safety threshold, it is determined that the furnace door is operating abnormally, and an instruction is immediately sent to the local control unit to cut off the power supply to the furnace door lifting motor.

[0073] In this embodiment, if the torque monitoring module detects that the motor current continuously exceeds the safety threshold during the lifting and lowering of the furnace door, the logic control module will determine that it is an abnormality such as limit switch failure and trigger an automatic emergency stop.

[0074] According to the appendix Figure 1 As shown, it is important to emphasize that the system's operating modes include:

[0075] Local manual mode: Controlled via control button 12 on the heat treatment furnace control box 1;

[0076] Remote manual mode: Controlled via a remote wireless remote control unit, allowing operators to perform emergency stops and furnace door operations from a safe location;

[0077] Automatic interlock mode: The safety interlock unit is in an active state and automatically performs safety monitoring and protection.

[0078] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A control and protection device for a heat treatment electric furnace, comprising a heat treatment electric furnace control box (1), characterized in that, The front end of the heat treatment furnace control box (1) is rotatably connected to a cabinet door (11). The cabinet door (11) is equipped with a control button (12) and a heat dissipation groove (13). The control button (12) is used to control the lifting and lowering of the furnace door. The heat dissipation groove (13) is used to dissipate heat from the circuit board and electrical components inside the heat treatment furnace control box (1). The bottom end of the heat treatment furnace control box (1) is provided with a knock-out hole (14). The knock-out hole (14) is used to pass through a data cable. The side end of the heat treatment furnace control box (1) is fixedly connected to a signal transmission unit (15). The signal transmission unit (15) is used to receive and transmit signals.

2. The system of a heat treatment electric furnace control and protection device according to claim 1, characterized in that, include: Local control unit, remote wireless control unit, and safety interlock unit; The local control unit is located in the heat treatment furnace control box (1), and the local control unit includes an execution circuit for controlling the lifting and lowering of the furnace door and an emergency stop protection circuit. The remote wireless control unit includes a handheld remote controller and a signal transmission unit (15). The signal transmission unit (15) is electrically connected to the local control unit. The signal transmission unit (15) is used to receive the wireless signal emitted by the remote controller and generate corresponding control commands. The safety interlock unit is connected to the signal transmission unit (15) via a signal; The remote wireless remote control unit can remotely trigger the emergency stop protection circuit in the local control unit to realize the emergency shutdown of the system; in addition, the remote wireless remote control unit can remotely simulate local operation signals to directly control the operation of the furnace door lifting and lowering actuator circuit. The safety interlock unit is used to monitor signals representing the forklift's operating status and the furnace door status signals. Based on preset safety logic, when a collision or equipment damage risk is detected, it automatically sends a control command to the local control unit to forcibly interrupt unsafe operations.

3. The system of a heat treatment electric furnace control and protection device according to claim 2, characterized in that, The remote wireless control unit controls the emergency stop protection circuit in the following ways: The receiver controls the coil circuit of an emergency stop intermediate relay; The normally closed contact of the emergency stop intermediate relay is connected in series in the main control power circuit of the local control unit; When an emergency stop command is issued via the remote control, the emergency stop intermediate relay is de-energized, its normally closed contact opens, thereby cutting off the power supply to the entire control circuit.

4. The system of a heat treatment electric furnace control and protection device according to claim 3, characterized in that, The remote wireless control unit controls the furnace door lifting and lowering actuator circuit in the following ways: The signal transmission unit (15) outputs furnace door raising and lowering commands, which are connected in parallel to the two ends of the locally controlled raising and lowering buttons, respectively; When an up or down command is issued via the remote control, it is equivalent to remotely triggering the local up or down button, thereby driving the corresponding up or down contactor to operate.

5. The system of a heat treatment electric furnace control and protection device according to claim 4, characterized in that, The safety interlock unit includes a proximity monitoring module and a logic control module; The proximity monitoring module is used to detect whether the forklift has entered the preset safe area in front of the furnace door. The forklift is equipped with a signal transmitter or positioning tag for identification. The logic control module is configured to: when a forklift is detected entering the detection area, immediately query the furnace door status; if the furnace door is not fully open, issue an emergency stop command to the local control unit to force the forklift automatic control system to stop.

6. The system of a heat treatment electric furnace control and protection device according to claim 5, characterized in that, The forklift proximity monitoring module uses one of the following: a UWB positioning sensor, an RFID area detection sensor, or a laser ranging sensor. The signal transmitter or positioning tag on the forklift is a matching UWB tag, RFID tag, or laser reflector.

7. The system of a heat treatment electric furnace control and protection device according to claim 6, characterized in that, The safety interlock unit includes a torque monitoring module; The torque monitoring module is used to monitor the operating current of the furnace door lifting motor or the force on the transmission mechanism in real time. When the detected current or pressure value exceeds the preset safety threshold, it is determined that the furnace door is operating abnormally, and an instruction is immediately sent to the local control unit to cut off the power supply to the furnace door lifting motor.

8. The system of a heat treatment electric furnace control and protection device according to claim 7, characterized in that, The system's operating modes include: Local manual mode: Controlled via the control button (12) on the heat treatment furnace control box (1); Remote manual mode: Controlled via the remote wireless remote control unit, the operator can perform emergency stops and furnace door operations from a safe position; Automatic interlock mode: The safety interlock unit is in an active state and automatically performs safety monitoring and protection.

Images