Three-wire system intelligent pressure switch circuit module with single-pole double-throw function

Abstract

The utility model relates to the technical field of pressure switches, and particularly discloses a three-wire system intelligent pressure switch circuit module with a single-pole double-throw function, which comprises an LDO (Low Dropout Regulator) circuit, an MCU (Microprogrammed Control Unit) driving circuit, a pressure signal circuit, a continuous power supply circuit, a pressure switch and two DCS (Distributed Control System), and the pressure switch comprises a common end, an active switch, a passive switch, an IGBT (Insulated Gate Bipolar Translator) tube, a triode and an MOS (Metal Oxide Semiconductor) tube. The module is internally provided with two common anode switches, the active switch is in a normally open state under a normal condition, the passive switch is in a normally closed state under a normal condition, after a circuit detects that the pressure reaches a set value, the active switch is closed, and meanwhile, the passive switch is linked to be opened, so that the use effect of single-pole double-throw is achieved. The utility model provides a novel pioneering circuit module, which can realize a three-wire system single-pole double-throw function, and fills the blank in the three-wire system single-pole double-throw intelligent switch technology.

Description

Technical Field

[0001] The utility model relates to the technical field of circuits, in particular to a three-wire intelligent pressure switch circuit module with a single-pole double-throw function. Background Art

[0002] Pressure switches are widely used in nuclear power plants and chemical industries, and are key equipment for pressure control and regulation in process control.

[0003] At present, the more common pressure switch is the mechanical pressure switch, but the mechanical pressure switch has the disadvantages of easy jamming, easy contact wear, and easy aging of elastic parts. Although the traditional electronic pressure switch does not have the above problems, it requires two separate wires to power the circuit part, and at least four wires are required to realize the single-pole double-throw function. Therefore, the manpower and material cost of on-site installation is more than 30% higher than that of mechanical pressure switches. At present, there is no three-wire intelligent switch that can realize single-pole double-throw.

[0004] Therefore, it is necessary to propose an improvement to overcome the defects of the prior art. Utility Model Content

[0005] The utility model aims to solve the problems in the prior art and provides a three-wire intelligent pressure switch circuit module with a single-pole double-throw function.

[0006] The technical solution of the utility model is:

[0007] A three-wire intelligent pressure switch circuit module with a single-pole double-throw function comprises: an LDO circuit, an MCU drive circuit, a pressure signal circuit, a continuous power supply circuit, a pressure switch and two DCSs, wherein the pressure switch comprises a common end, an active switch, a passive switch, an IGBT tube, a triode and a MOS tube, wherein the common end is connected to VCC, the active switch and the passive switch are respectively connected to a DCS, the common end is connected to an LDO circuit input end, an IGBT tube collector, a triode collector and a MOS tube source, the LDO circuit output end is connected to an MCU drive circuit input end, the MCU drive circuit output end is connected to an IGBT tube grid and a triode base, the MCU drive circuit is connected to a pressure signal circuit, the IGBT tube emitter is connected to an active switch, the IGBT tube collector is connected to a triode collector, the triode emitter is connected to a continuous power supply circuit input end, the continuous power supply circuit output end is connected to an LDO circuit input end, the MOS tube drain is connected to a passive switch, the MOS tube grid is connected to an IGBT tube emitter and an active switch via a second resistor, and a first resistor is connected in parallel between the source and grid of the MOS tube.

[0008] Under normal circumstances, the active switch is in the normally open state and the passive switch is in the normally closed state. When the circuit detection pressure reaches the set value, the active switch is closed and the passive switch is linked to open, achieving the effect of single-pole double-throw.

[0009] As a preferred technical solution, the pressure switch also includes a first diode, the anode of the first diode is connected to the output end of the MCU drive circuit, and the cathode of the first diode is connected to the gate of the IGBT and the base of the transistor.

[0010] As a preferred technical solution, the pressure switch further includes a second diode, the anode of the second diode is connected to the drain of the MOS tube, and the cathode of the second diode is connected to the passive switch.

[0011] As a preferred technical solution, the MOS tube is of PNP type.

[0012] Compared with the prior art, the utility model has the following beneficial effects:

[0013] (1) No need to lay additional cables;

[0014] (2) Compared with traditional electronic pressure switches, it saves at least one cable, greatly reducing installation costs;

[0015] (3) Single-pole double-throw is realized, which expands the application range of the intelligent switch. The same position can be controlled by one device, avoiding the embarrassment of requiring two devices to control the same control position;

[0016] (4) This pressure switch circuit module solution can also be used in products such as differential pressure switches and temperature switches. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the working mode of the three-wire single-pole double-throw intelligent pressure switch of the utility model;

[0018] Figure 2 This is a schematic diagram of a three-wire intelligent pressure switch circuit module with a single-pole double-throw function of the utility model; DETAILED DESCRIPTION

[0019] In order to make the technical means, technical features, utility model objectives and technical effects achieved by the utility model easy to understand, the utility model is further explained below with reference to specific illustrations.

[0020] like Figure 1 and Figure 2As shown, the utility model is a three-wire intelligent pressure switch circuit module with a single-pole double-throw function, including: an LDO circuit, an MCU drive circuit, a pressure signal circuit, a continuous power supply circuit, a pressure switch and two DCSs, and the pressure switch includes a common end, an active switch, a passive switch, an IGBT tube, a triode and a MOS tube.

[0021] In this embodiment, pin 2 of the pressure switch is the common terminal, pin 1 is the active switch connected to the DI detection port of DCS1, and pin 3 is the passive switch connected to the DI detection port of DCS2. Normally, pin 1 is disconnected and pin 3 is closed. When the pressure triggers the set value, pin 1 is closed and pin 3 is opened.

[0022] The common terminal 2 pin is connected to the LDO circuit input end, the IGBT tube Q1 collector, the transistor Q2 collector and the MOS tube Q3 source, the LDO circuit output end is connected to the MCU drive circuit input end, the MCU drive circuit output end is connected to the first diode D1 positive electrode, the first diode D1 negative electrode is connected to the IGBT tube Q1 gate and the transistor Q2 base, the MCU drive circuit is connected to the pressure signal circuit, the IGBT tube Q1 emitter is connected to the active switch 1 pin, the IGBT tube Q1 collector is connected to the transistor Q2 collector, the transistor Q2 emitter is connected to the continuous power supply circuit input end, the continuous power supply circuit output end is connected to the LDO circuit input end, the MOS tube Q3 drain is connected to the second diode D2 positive electrode, the second diode D2 negative electrode is connected to the passive switch 3 pin, the MOS tube Q3 gate is connected to the IGBT tube Q1 emitter and the active switch 1 pin through the second resistor R2, and the first resistor R1 is connected in parallel between the source and the gate of the MOS tube Q3.

[0023] MCU detects the pressure signal, compares it with the set value, and controls the disconnection or conduction of IGBT tube Q1. When IGBT tube Q1 is disconnected, pin 1 outputs a low-level switch quantity, and when IGBT tube Q1 is turned on, pin 1 outputs a high-level switch quantity; the corresponding output switch quantity of pin 3 is opposite to the output switch quantity of pin 1, achieving the effect of single-pole double-throw working mode. The LDO circuit powers the MCU drive circuit and the pressure signal circuit when the IGBT tube Q1 is disconnected, and the transistor Q2 and the continuous power supply circuit power the MCU drive circuit and the pressure signal circuit when the IGBT tube Q1 is turned on.

[0024] After VCC is stepped down by LDO, it supplies power to MCU. LDO is a low static current power consumption device with a power consumption of only a few uA. The MCU uses a low power consumption mode model, and the average power consumption is maintained below 10uA. After the MCU collects the pressure signal and processes it into physical information, it compares it with the set value. If the set value is reached, the drive output is high, otherwise, it maintains a low level. When the output is low, the overall power consumption is maintained below 100uA.

[0025] At the initial power-on, the drive signal D1 is at a low level, the current through DCS1 is below 100uA, and the DCS1 detection voltage is at a low level. MOS tube Q3 is a PNP type, and VCC is divided by the first resistor R1 and the second resistor R2, so that the MOS tube Q3Vgs drive voltage range is -4~-20V, MOS tube Q3 is turned on, and the VCC voltage is applied to DCS2, and the voltage detected by the DI port of DCS2 is high. That is, the pressure switch is in a single-pole double-throw mode with DCS1 low level and DCS2 high level.

[0026] After the MCU detects that the pressure signal reaches the set value, the MCU drives the output high level, the IGBT tube Q1 is turned on, VCC is applied to DCS1, and the DI port of DCS1 detects a high level. At this time, the transistor Q2 is turned on at the same time. The voltage generated by the IGBT tube Q1Vds voltage drop is doubled and rectified to continuously power the MCU and pressure signal acquisition. At the same time, because the IGBT tube Q1Vds voltage is reduced to about 2V, the MOS tube Q3Vgs drive voltage is removed, the MOS tube Q3 is turned off, and the DI port of DCS2 cannot detect the voltage, which is a low level. That is, the pressure switch is in a single-pole double-throw mode with a high level for DCS1 and a low level for DCS2.

[0027] The above description is only a preferred embodiment of the utility model, and is not intended to limit the scope of implementation of the utility model. That is, all equivalent changes and modifications made according to the content of the patent application scope of the utility model should belong to the technical scope of the utility model.

Claims

1. A three-wire intelligent pressure switch circuit module with single-pole double-throw function, characterized in that: include: An LDO circuit, an MCU driving circuit, a pressure signal circuit, a continuous power supply circuit, a pressure switch and two DCSs, wherein the pressure switch comprises a common end, an active switch, a passive switch, an IGBT tube, a triode and a MOS tube, wherein the common end is connected to VCC, the active switch and the passive switch are respectively connected to a DCS, the common end is connected to the LDO circuit input end, the IGBT tube collector, the triode collector and the MOS tube source, the LDO circuit output end is connected to the MCU driving circuit input end, the MCU driving circuit output end is connected to the IGBT tube gate and the triode base, the MCU driving circuit is connected to the pressure signal circuit, the IGBT tube emitter is connected to the active switch, the IGBT tube collector is connected to the triode collector, the triode emitter is connected to the continuous power supply circuit input end, the continuous power supply circuit output end is connected to the LDO circuit input end, the MOS tube drain is connected to the passive switch, the MOS tube gate is connected to the IGBT tube emitter and the active switch through a second resistor, and a first resistor is connected in parallel between the source and the gate of the MOS tube.

2. A three-wire intelligent pressure switch circuit module with single-pole double-throw function according to claim 1, characterized in that: The pressure switch also includes a first diode, wherein the anode of the first diode is connected to the output end of the MCU drive circuit, and the cathode of the first diode is connected to the gate of the IGBT tube and the base of the transistor.

3. A three-wire intelligent pressure switch circuit module with single-pole double-throw function according to claim 1 or 2, characterized in that: The pressure switch further includes a second diode, wherein the anode of the second diode is connected to the drain of the MOS tube, and the cathode of the second diode is connected to the passive switch.

4. The three-wire intelligent pressure switch circuit module with single-pole double-throw function according to claim 1 is characterized in that: The MOS tube is of PNP type.

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