Mold temperature controller anti-runaway protection device

Abstract

The utility model discloses a kind of mould temperature controller anti-runaway protection devices, include: heating main circuit, including circuit breaker QF2, solid-state relay SCR and electric heating rod EH1;Circulation power main circuit, including circuit breaker QF1, contactor KM1, thermal overload relay FR1 and motor M1;Central control unit PC is equipped with several input ports and output ports;Temperature sampling circuit, including thermocouple TC and over-temperature protection switch BK1;Current detection circuit, including respectively being packaged in the current relay CT-A, CT-B, CT-C of heating main circuit's A phase, B phase, C phase;Circuit breaker tripping circuit, including circuit breaker shunt release tripping device QF2-MX and circuit breaker auxiliary contact QF2-OF, circuit breaker shunt release tripping device QF2-MX coil one end connects the output port of central control unit PC, other end connects zero line, circuit breaker auxiliary contact QF2-OF connects the input port of central control unit PC.The mould temperature controller anti-runaway protection device of the utility model, additional circuit breaker shunt release tripping device, PC directly drives its coil instantaneous trip, and safety level is promoted.

Description

Technical Field

[0001] This utility model specifically relates to a mold temperature controller anti-runaway protection device. Background Technology

[0002] Mold temperature controllers use electric heating rods to heat the heat transfer medium and circulate it to the mold to stabilize the molding temperature. Existing equipment generally uses a temperature controller to drive a contactor or solid-state relay to switch the heating circuit on and off, and uses thermocouples for single-point temperature feedback. This solution is simple in structure and low in cost, but under long-term, frequent start-stop conditions, the contactor coil is prone to sticking, and the solid-state relay may also be continuously conducting due to surge breakdown. Once the temperature controller output point is damaged or the thermocouple drifts, the control circuit will fail, leaving the heating rod in an uncontrolled, continuously connected state, causing the heat transfer medium to overheat. This can result in product scrapping or, in severe cases, a fire. Furthermore, motor overload protection relies on independent tripping of the thermal relay, lacking linkage with the heating circuit, making it difficult for maintenance personnel to centrally upload fault information and locate the cause immediately.

[0003] Therefore, the industry urgently needs a runaway prevention device that is simple in structure, moderate in cost, can simultaneously perform real-time detection and power-off protection of the heating main circuit and motor circuit, and has local alarm function, in order to improve equipment safety. Utility Model Content

[0004] This utility model provides a mold temperature controller anti-runaway protection device to solve the above-mentioned technical problems, and the specific technical solution is as follows: A mold temperature controller anti-runaway protection device, comprising: The heating main circuit includes a circuit breaker QF2, a solid-state relay SCR, and an electric heating rod EH1, wherein the circuit breaker QF2, the solid-state relay SCR, and the electric heating rod EH1 are connected in series. The circulating power main circuit includes circuit breaker QF1, contactor KM1, thermal overload relay FR1 and motor M1, wherein the circuit breaker QF1, the contactor KM1, the thermal overload relay FR1 and the motor M1 are connected in series. The central control unit (PC) is equipped with several input and output ports. The temperature sampling circuit includes a thermocouple TC and an over-temperature protection switch BK1. The thermocouple TC is connected to the input port of the central control unit PC, and one end of the over-temperature protection switch BK1 is connected to the input port of the central control unit PC, and the other end is connected to a common terminal. The current detection circuit includes current relays CT-A, CT-B, and CT-C respectively installed in phases A, B, and C of the heating main circuit. The secondary sides of the current relays CT-A, CT-B, and CT-C are all connected to the corresponding input ports of the central control unit PC. The circuit breaker tripping circuit includes a circuit breaker shunt trip unit QF2-MX and a circuit breaker auxiliary contact QF2-OF. One end of the coil of the circuit breaker shunt trip unit QF2-MX is connected to the output port of the central control unit PC, and the other end is connected to the neutral wire. The circuit breaker auxiliary contact QF2-OF is connected to the input port of the central control unit PC. The normally closed auxiliary contact of the thermal overload relay FR1 is connected to the input port of the central control unit PC. The central control unit PC is connected to the KM1 coil, the SCR control terminal, and the QF2-MX coil through its output port.

[0005] Furthermore, the current relays CT-A, CT-B, and CT-C are respectively mounted on phases A, B, and C between the solid-state relay SCR and the electric heating rod EH1.

[0006] Furthermore, the mold temperature controller anti-runaway protection device also includes: The audible and visual alarm HA is connected to the digital output port of the PC, and the central control unit PC is connected through the digital output port HA.

[0007] Furthermore, the main contacts of the contactor KM1 are connected in series in the power supply circuit of the motor M1, and the coil of KM1 is connected to the output port of the central control unit PC.

[0008] Furthermore, the over-temperature protection switch BK1 is a normally closed temperature switch, and its two ends of the wires are directly led to the input port and common terminal of the central control unit PC.

[0009] Furthermore, the wires at both ends of the normally closed auxiliary contact of the thermal overload relay FR1 are directly led to the input port and common terminal of the central control unit PC.

[0010] Furthermore, the motor M1 is an oil circulation pump, and its power supply terminal is connected to the main contact of the thermal overload relay FR1. The other end of the main contact of the thermal overload relay FR1 is connected to the main contact of the contactor KM1.

[0011] The advantage of this utility model lies in the provision of a runaway protection device for the mold temperature controller, which adds a circuit breaker shunt trip unit, and the PC directly drives its coil to trip instantaneously, disconnecting the main circuit before the contactor / SCR, thus preventing the device from continuing to heat up, improving the safety level and reducing maintenance. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of this application 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 this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a partial circuit diagram of a mold temperature controller anti-runaway protection device according to this utility model; Figure 2 This is another circuit diagram of a mold temperature controller anti-runaway protection device of this utility model. Detailed Implementation

[0014] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0015] like Figure 1 and 2 As shown, this application discloses a mold temperature controller anti-runaway protection device, including: a heating main circuit, a circulating power main circuit, a temperature sampling circuit, a current detection circuit, a circuit breaker tripping circuit, and a central control unit PC. All signal lines are connected to the central control unit PC through terminal blocks for easy maintenance.

[0016] The main heating circuit includes circuit breaker QF2, solid-state relay SCR, and electric heating rod EH1, which are connected in series to heat the heat transfer medium. Specifically, the three-phase mains power L1 / L2 / L3 is supplied to the three-phase main terminals of the solid-state relay SCR after passing through circuit breaker QF2. The SCR output is directly connected to the electric heating rod EH1. The positive and negative terminals of the SCR control terminal are driven by the PC output port; when the PC provides a conduction level, the SCR conducts, EH1 is energized and heats up, and the temperature of the heat transfer medium rises accordingly. The rated current of QF2 is selected according to the power of EH1, and it trips instantaneously in the event of a short circuit.

[0017] The main circulating power circuit includes circuit breaker QF1, contactor KM1, thermal overload relay FR1, and motor M1. These components are connected in series to drive the circulation of the heat-conducting medium. Another three-phase power supply passes through circuit breaker QF1, the main contacts of contactor KM1, and the main contacts of thermal overload relay FR1 to motor M1. The KM1 coil is controlled by the PC output port. The FR1 main contacts are connected in series in the motor power supply path. When motor M1 is overloaded, FR1 sends a signal to the PC. Upon receiving the overload signal, the PC disconnects the KM1 main circuit, thus protecting the motor. The central control unit (PC) has several input and output ports. This embodiment uses a commercially available transistor-output programmable logic controller (PLC) with a built-in 24V DC power supply, providing multiple input and output ports. After power-on, the PC samples data cyclically at a fixed period and executes subsequent control logic. All ports are connected to external components via pluggable terminal blocks for easy field replacement.

[0018] The temperature sampling circuit includes a thermocouple TC and an over-temperature protection switch BK1. Thermocouple TC is connected to the input port of the central control unit (PC), and one end of the over-temperature protection switch BK1 is connected to the input port of the PC, while the other end is connected to a common terminal. When the oil temperature reaches the set upper limit, BK1 disconnects, and the PC immediately recognizes it as an over-temperature event.

[0019] The current detection circuit includes current relays CT-A, CT-B, and CT-C, respectively installed on phases A, B, and C of the main heating circuit. The secondary sides of each current relay CT-A, CT-B, and CT-C are connected to the corresponding input ports of the central control unit (PC). Specifically, the current relays CT-A, CT-B, and CT-C are installed on phases A, B, and C between the solid-state relay (SCR) and the electric heating rod (EH1). The central control unit (PC) calculates the effective value at regular intervals and compares it with a preset threshold. If it detects "no current despite heating should be present" or "current should be present despite stopping," it determines that the main circuit is out of control.

[0020] The circuit breaker tripping circuit includes the circuit breaker shunt trip unit QF2-MX and the circuit breaker auxiliary contact QF2-OF. One end of the coil of the circuit breaker shunt trip unit QF2-MX is connected to the output port of the central control unit PC, and the other end is connected to the neutral wire. The circuit breaker auxiliary contact QF2-OF is connected to the input port of the central control unit PC, and the other end is connected to the common terminal COM, used to provide feedback to the PC on the actual opening and closing status of QF2. The normally closed auxiliary contact of the thermal overload relay FR1 is connected to the input port of the central control unit PC. The central control unit PC is connected to the KM1 coil, the SCR control terminal, and the QF2-MX coil through its output port. When an over-temperature signal or an abnormal signal from the current relay occurs, the PC will output a circuit breaker shunt trip signal, thereby cutting off the main power supply to the heating rod for protection. When the central control unit PC issues a trip signal, the corresponding output port immediately outputs a high level, QF2-MX is momentarily energized, forcing QF2 to trip, and the entire heating main circuit is de-energized, fundamentally eliminating the risk of continuous heating.

[0021] In the embodiments of this application, the mold temperature controller anti-runaway protection device further includes an audible and visual alarm HA. The audible and visual alarm HA is connected to the digital output port of the PC, and the central control unit PC is connected through the digital output port HA.

[0022] When the central control unit PC receives an over-temperature signal, an overcurrent or no-current signal from CT-A / CT-B / CT-C, a trip signal from QF2-OF, or an action signal from FR1, it outputs a trip signal to activate QF2-MX and drive the HA alarm.

[0023] In the embodiments of this application, the main contacts of contactor KM1 are connected in series in the power supply circuit of motor M1, and the coil of KM1 is connected to the output port of the central control unit PC.

[0024] In the embodiments of this application, the over-temperature protection switch BK1 is a normally closed temperature switch, and its two ends of the wires are directly led to the input port and common terminal of the central control unit PC.

[0025] In the embodiments of this application, the wires at both ends of the normally closed auxiliary contact of the thermal overload relay FR1 are directly led to the input port and common terminal of the central control unit PC.

[0026] In the embodiments of this application, the motor M1 is an oil circulation pump, and its power supply terminal is connected to the main contact of the thermal overload relay FR1. The other end of the main contact of the thermal overload relay FR1 is connected to the main contact of the contactor KM1.

[0027] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that the above embodiments do not limit this utility model in any way, and all technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of this utility model.

Claims

1. A mold temperature controller anti-runaway protection device, characterized in that, include: The heating main circuit includes a circuit breaker QF2, a solid-state relay SCR, and an electric heating rod EH1, wherein the circuit breaker QF2, the solid-state relay SCR, and the electric heating rod EH1 are connected in series. The circulating power main circuit includes circuit breaker QF1, contactor KM1, thermal overload relay FR1 and motor M1, wherein the circuit breaker QF1, the contactor KM1, the thermal overload relay FR1 and the motor M1 are connected in series. The central control unit (PC) is equipped with several input and output ports. The temperature sampling circuit includes a thermocouple TC and an over-temperature protection switch BK1. The thermocouple TC is connected to the input port of the central control unit PC, and one end of the over-temperature protection switch BK1 is connected to the input port of the central control unit PC, and the other end is connected to a common terminal. The current detection circuit includes current relays CT-A, CT-B, and CT-C respectively installed in phases A, B, and C of the heating main circuit. The secondary sides of the current relays CT-A, CT-B, and CT-C are all connected to the corresponding input ports of the central control unit PC. The circuit breaker tripping circuit includes a circuit breaker shunt trip unit QF2-MX and a circuit breaker auxiliary contact QF2-OF. One end of the coil of the circuit breaker shunt trip unit QF2-MX is connected to the output port of the central control unit PC, and the other end is connected to the neutral wire. The circuit breaker auxiliary contact QF2-OF is connected to the input port of the central control unit PC. The normally closed auxiliary contact of the thermal overload relay FR1 is connected to the input port of the central control unit PC. The central control unit PC is connected to the KM1 coil, the SCR control terminal, and the QF2-MX coil through its output port.

2. The mold temperature controller anti-runaway protection device according to claim 1, characterized in that, The current relays CT-A, CT-B, and CT-C are respectively installed between the solid-state relay SCR and the electric heating rod EH1, corresponding to phases A, B, and C.

3. The mold temperature controller anti-runaway protection device according to claim 1, characterized in that: The mold temperature controller anti-runaway protection device also includes: The audible and visual alarm HA is connected to the digital output port of the PC, and the central control unit PC is connected through the digital output port HA.

4. The mold temperature controller anti-runaway protection device according to claim 1, characterized in that: The main contacts of the contactor KM1 are connected in series in the power supply circuit of the motor M1, and the coil of KM1 is connected to the output port of the central control unit PC.

5. The anti-runaway protection device for mold temperature controller according to claim 1, characterized in that: The over-temperature protection switch BK1 is a normally closed temperature switch, and its two ends of the wires are directly led to the input port and common terminal of the central control unit PC.

6. The anti-runaway protection device for mold temperature controller according to claim 1, characterized in that: The wires at both ends of the normally closed auxiliary contact of the thermal overload relay FR1 are directly led to the input port and common terminal of the central control unit PC.

7. The mold temperature controller anti-runaway protection device according to claim 1, characterized in that: The motor M1 is an oil circulation pump, and its power supply terminal is connected to the main contact of the thermal overload relay FR1. The other end of the main contact of the thermal overload relay FR1 is connected to the main contact of the contactor KM1.

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