Fan control switching equipment, ventilation control system and switching control method

Abstract

The invention discloses fan control switching equipment, a ventilation control system and a switching control method, and belongs to the technical field of ventilation control. The equipment comprises an outer shell and a control circuit board, a logic circuit, a gear control circuit, a communication circuit and a wireless communication module are arranged on the control circuit board; the outer shell is provided with a first digital communication interface, a second digital communication interface and a gear control interface; the communication circuit is connected with the environment controller through a first digital communication interface and is also connected with the fan through a second digital communication interface; the gear control circuit is respectively connected with the power supply box through a plurality of gear control switches of the gear control interface; the power supply box is connected with the fan; when the plurality of gear control switches are all switched off, the first digital communication interface and the second digital communication interface are started for transmitting digital signals; when at least one gear control switch is grounded, the first digital communication interface and the second digital communication interface are shielded for transmitting analog voltage signals. The advantages of low cost, fast response, reliable connection, easy maintenance and the like are realized.

Description

Technical Field

[0001] This invention belongs to the field of ventilation control technology, specifically relating to a fan control switching device, a ventilation control system, and a switching control method. Background Technology

[0002] In existing ventilation control systems, EC fans and environmental controllers are core components. For example, in the prior art, Chinese patent with publication number CN204888289U discloses an automatic ventilation control device for pigsties. This device includes a fully automatic ventilation control system and a fan control system. The fully automatic ventilation control system includes an environmental controller, which is connected to a temperature sensor, a fan, and a sliding window. An alarm device is installed inside the environmental controller.

[0003] While the aforementioned existing technologies can address the issue of inadequate control over the pig-raising environment due to differences in pig-raising skills among farmers, the following technical shortcomings still exist in practical applications: First, some current ventilation control systems lack dedicated control switching tools. When the interface encounters a high surge or the user connects the wrong wires for debugging, it is very easy to damage the expensive EC fan interface or environmental controller interface. This requires replacing the control board of the EC fan or the control board of the environmental controller. However, replacing the control board of the EC fan or the control board of the environmental controller costs hundreds to thousands of yuan, resulting in high maintenance costs. Secondly, some existing ventilation control systems also have control switching tools, but these control switching tools usually integrate complex components such as microcontrollers, displays and 4G modules; therefore, from the perspective of component usage, the component usage cost of traditional control switching tools is high. Third, traditional control switching tools use microcontrollers, and their data signals need to be processed by the microcontroller before being sent to the EC fan or environmental controller, which inevitably results in communication delays. Fourth, traditional control switching tools use 4G modules, which usually require a GPRS network and a server to achieve data transmission. Moreover, although traditional control switching tools can achieve more remote wireless communication control through a server, they are subject to risks such as network attacks and server instability, and require continuous payment of network service fees. Fifth, the existing ventilation control functions are integrated into the EC fan, resulting in numerous and complex wiring connections from the electrical box to the fan, leading to high costs, maintenance difficulty, and maintenance expenses.

[0004] Therefore, there is an urgent need for a low-cost, fast-responding, reliable, and easy-to-maintain wind turbine control and switching device. Summary of the Invention

[0005] To address the problems in related technologies, this invention proposes a fan control switching device, a ventilation control system, and a switching control method to overcome the aforementioned technical problems in existing related technologies. This invention achieves reliable switching between digital communication and analog voltage control through the fan control switching device, and also conveniently realizes multi-speed adjustment of the fan. Furthermore, this invention also has the advantages of low cost, rapid response, and easy maintenance.

[0006] The technical solution of the present invention is implemented as follows: a fan control switching device includes a housing, and a control circuit board is provided inside the housing; The control circuit board integrates logic circuits and a built-in power supply. The control circuit board also includes a gear control circuit, a communication circuit, and a wireless communication module, which are respectively connected to the logic circuit. The wireless communication module is used to establish a wireless communication connection with an external mobile terminal. The outer casing is provided with a first digital communication interface, a second digital communication interface, a gear control interface, and a power input interface; the communication circuit is connected to the environmental controller via the first digital communication interface; the communication circuit is also connected to the fan via the second digital communication interface; the gear control interface has multiple gear control switches; the gear control circuit is connected to the control switches of the power supply box via the multiple gear control switches respectively. Furthermore, the multiple speed control switches correspond to different speed settings of the fan. The power supply box is connected to the fan via an analog voltage control line, and the power supply box is used to send analog voltage signals to the fan. Furthermore, the power supply box sends an analog voltage signal of 0~10V to the fan; When all the gear control switches are in the off state, the logic circuit enables the first and second digital communication interfaces. At this time, a digital communication link is established between the environmental controller and the fan for transmitting digital signals. When at least one gear control switch is in the short ground wire state, the logic circuit shields the first and second digital communication interfaces. At this time, the environmental controller establishes an analog communication link between the power supply box and the fan for transmitting analog voltage signals. The gear control circuit is electrically connected to the built-in power supply, and the built-in power supply is electrically connected to the fan through the power input interface.

[0007] Furthermore, the communication circuit includes a 485 chip circuit and a first protection circuit; The 485 chip circuit includes chip U2 and chip U3; the first protection circuit is connected to chip U2 and chip U3 respectively through a 485B2-in interface; the 485B2 interface of the first protection circuit forms the first digital communication interface; chip U3 is also connected to the logic circuit through a DE1 interface, a UART-RX interface, and a UART-TX interface; chip U2 is also connected to the logic circuit through a DE2 interface, a UART-RX interface, and a UART-TX interface; chip U2 is connected to chip U3 respectively through UART-RX and UART-TX interfaces. Preferably, both chip U2 and chip U3 are RS485 chips; Furthermore, pin R of chip U3 is connected to resistor R12 and capacitor C14 respectively, and the other end of capacitor C14 is grounded; resistor R12 is then connected to the UART-RX interface; pin RE and pin DE of chip U3 are simultaneously connected to resistor R19, resistor R19 is connected to capacitor C15, and the other end of capacitor C15 is grounded. Furthermore, pin R of chip U2 is connected to resistor R11 and capacitor C12 respectively, with the other end of capacitor C12 grounded; resistor R11 is connected in series with resistor R7, resistor R8, and UART-RX interface in sequence; pin D of chip U2 is connected to the UART-RX interface; resistor R11 is also connected to the UART-TX interface of chip U3; pins RE and DE of chip U2 are simultaneously connected to resistor R18, resistor R18 is connected to capacitor C13, with the other end of capacitor C13 grounded. Furthermore, the first protection circuit includes a resistor R17, a current-limiting resistor R5, and bidirectional breakdown diodes D13 and D14; one end of the bidirectional breakdown diode D13 is connected to the resistor R17 and the bidirectional breakdown diode D14 respectively, and the other end is grounded; the other end of the resistor R17 is connected to the 485B2 interface; one end of the bidirectional breakdown diode D14 is connected to the current-limiting resistor R5 and the 485B2-in interface in sequence.

[0008] Furthermore, the communication circuit also includes a second protection circuit; the second protection circuit is connected to chip U3 and chip U2 respectively through a 485A2-in interface; the 485A2 interface of the second protection circuit forms the second digital communication interface; The second protection circuit includes a resistor R20, a current-limiting resistor R21, and a bidirectional breakdown diode D16; the other end of the bidirectional breakdown diode D14 is connected to the resistor R20, the bidirectional breakdown diode D16, and the current-limiting resistor R21 respectively; the resistor R20 is then connected to the 485A2 interface; the current-limiting resistor R21 is then connected to the 485A2-in interface; the other end of the bidirectional breakdown diode D16 is grounded. Preferably, resistors R17 and R20 are PTC thermistors, model nSMD010; bidirectional breakdown diodes D13, D14, and D16 are all model SMBJ6.5CA; and current-limiting resistors R5 and R21 have a resistance of 10Ω. Furthermore, the PTC thermistor and bidirectional breakdown diode, combined with the PTC resettable fuse and bidirectional TVS transient diode, are used to control the incoming current and voltage clamping. Preferably, both chip U2 and chip U3 are RS485 chips, the model of which is SP485EEN, and the two RS485 chips are designed back to back; capacitors C12 to C15 are all filter capacitors; resistors R7 and R8 are pull-up resistors; resistors R11, R12, R18, and R19 are all current-limiting resistors.

[0009] Furthermore, the logic circuit includes an inverter U4, whose UART-RX and UART-TX interfaces are connected to the chip U2 and chip U3 respectively; the DE1 interface of the inverter U4 is connected to the chip U3; and the DE2 interface of the inverter U4 is connected to the chip U2. The logic circuit also includes diodes D15 and D18, resistors R23 and R27, and capacitors C9 and C11; wherein, one end of resistor R23 is connected to the 1A interface of inverter U4 and capacitor C9 respectively, and the other end of resistor R23 is connected to the UART-RX interface; diode D15 is connected in parallel across resistor R23. One end of resistor R27 is connected to the 2A interface of inverter U4 and capacitor C11 respectively, and the other end of resistor R27 is connected to UART-TX interface; diode D18 is connected in parallel across resistor R27; capacitor C9 is connected in series with capacitor C11. Furthermore, resistor R23 and capacitor C9 form the first RC filter; resistor R27 and capacitor C11 form the second RC filter. Furthermore, the inverter U4 is model SN74LVC2G14; diodes D15 and D18 are both Schottky diodes, model B5817.

[0010] Furthermore, the gear control circuit includes a DI control circuit and a third protection circuit. The DI control circuit is connected to the plurality of gear control switches through the third protection circuit. The DI control circuit is also connected to the built-in power supply and the logic circuit, respectively. Furthermore, the third protection circuit includes diode D19 and Zener diode D20, with Zener diode D20 being an SMBJ6.5 type; the negative terminal of Zener diode D20 is connected to the negative terminal of diode D19, and the positive terminal of Zener diode D20 is grounded; one port of the DI1 level line is connected between transient suppression diode D2 and diode D19; Furthermore, the DI control circuit includes transistors Q2, Q4, Q5, and Q7, diodes D3 and D7, and a Zener diode D10; the cathode of the Zener diode D10 is connected to the cathodes of diodes D3 and D7 respectively, and the anode of the Zener diode D10 is grounded; one port of the DI2 level line is connected between diodes D3 and D10; The DI control circuit also includes bias resistors R1, R4, R25, R26, R30, and R31, and a pull-down resistor R28. The two ends of the pull-down resistor R28 are connected in parallel to the collector and emitter of transistor Q5, with the emitter grounded. The base of transistor Q5 is connected to the bias resistor R25 and the collector of transistor Q7, respectively. The emitter of transistor Q5 is connected to the DE1 and DE2 interfaces in the logic circuit via the DEx interface. The emitter of transistor Q7 is grounded, and the base of transistor Q7 is connected to the bias resistor R31. The two ends of the bias resistor R26 are connected in parallel to the collector and emitter of transistor Q5, respectively. The bias resistors R25 and R31 are connected; the bias resistor R31 is connected to the anode of the diode D19; the bias resistor R26 is connected to the anode of the diode D3; the two ends of the bias resistor R1 are connected in parallel with the collector and base of the transistor Q2, respectively, and the emitter of the transistor Q2 is electrically connected to the built-in power supply for inputting a 0-10V voltage; the collector of the transistor Q4 is connected to the base of the transistor Q2, and the base of the transistor Q4 is connected in sequence to the bias resistors R4 and R30, and the bias resistor R30 is also connected to the anode of the diode D7; the emitter of the transistor Q4 is grounded. Preferably, transistors Q2, Q4, Q5, and Q7 are all MMBT5551. Preferably, diodes D3, D7, and D19 are all of type B5819.

[0011] Furthermore, the plurality of gear control switches include switches DI1 to DI4; when switch DI1 is short-grounded, the output analog voltage signal is defined by the power supply box; when any one of switches DI2 to DI4 is short-grounded, it is used to output different preset voltage signals inside the logic circuit respectively.

[0012] Furthermore, when switches DI1 to DI4 are simultaneously short-grounded, the control logic corresponding to the highest priority gear control switch is executed in ascending order of priority from switch DI1 to switch DI4.

[0013] Furthermore, the wireless communication module is a Bluetooth module with serial port functionality. The Bluetooth module is configured to establish a point-to-point wireless communication connection with the external mobile terminal, eliminating the need for data transmission via a server. After the Bluetooth module receives data from the external mobile terminal, the logic circuit sends it to the wind turbine through the second digital communication interface. After the wind turbine sends data through the second digital communication interface, the logic circuit sends it to the external mobile terminal through the Bluetooth module. Furthermore, the external mobile terminal is a mobile app, which is used to receive data from the Bluetooth module and to send data to the Bluetooth module. Furthermore, chip U2 is connected to chip U3 via UART-RX and UART-TX interfaces respectively, forming a serial port connection between two RS485 chips; the Bluetooth module is connected to UART-RX and UART-TX interfaces respectively, so that the Bluetooth module is connected in parallel in the serial port signals of the two RS485 chips. Furthermore, the Bluetooth module requires a key to connect to the mobile app, ensuring a private connection.

[0014] A ventilation control system includes an environmental controller and a fan, as well as the aforementioned fan control switching device; The first digital communication interface of the wind turbine control switching device is connected to the environmental controller, and the second digital communication interface of the wind turbine control switching device is connected to the wind turbine.

[0015] A fan switching control method, applied to the aforementioned ventilation control system, the method comprising the following steps: Step S1: Pre-set one of the gear control switches as the first gear control switch, and the remaining gear control switches as the second, third, and fourth gear control switches respectively; the fan control switching device internally presets different voltage values ​​corresponding to different gear control switches, and different gear control switches correspond to different speed gears of the fan; the logic circuit monitors whether each gear control switch is in the open state or the short ground wire state; Step S2: Digital mode execution; if all gear control switches are not short-circuited to the ground wire, a digital communication link is established between the environmental controller and the fan, and the environmental controller controls the fan through digital signals; Step S3: Analog mode execution. If any gear control switch is detected to be short-circuited by a ground wire, the digital communication link is interrupted, and analog voltage signal output is initiated. Specifically, the analog mode execution includes: Step S3a: If the short ground wire is the first gear control switch, the power supply box outputs a 0~10V analog voltage signal to the fan; Step S3b: If the short ground wire is the control switch for the second, third, or fourth gear position, the fan control switching device outputs the internal preset voltage value corresponding to the control switch for that gear position, and the fan switches the corresponding speed gear according to the different voltage values.

[0016] It should be noted that in step S3, if multiple gear control switches are detected to be short-grounded at the same time, the control logic corresponding to the gear control switch with the highest priority is executed according to the preset priority order.

[0017] The beneficial effects of this invention are: (1) In practical applications, the fan control switching device described in this invention can be implemented for only tens of RMB, which can effectively protect expensive fans and environmental controllers, and greatly reduce maintenance and debugging costs for users.

[0018] (2) In terms of the use of components, traditional switching tools have more and more complex components than the fan control switching device described in this invention. This invention only uses simple resistors, capacitors, RS485 chips, logic circuits and Bluetooth modules, and its cost is much lower than that of traditional switching tools.

[0019] (3) The present invention does not require the use of a microcontroller. The digital signal of the fan control switching device described in the present invention is directly connected to the fan, realizing direct transmission of digital signals and faster signal transmission speed.

[0020] (4) The multi-level control switches of the fan control switching device are directly led out. The user leads all the level control switches to the user's power supply box, which is equivalent to the fan control switching device being directly installed on the power supply box. The amount of wiring used is far less than that of the traditional method. Therefore, the present invention has the advantage of easy maintenance. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the interface structure of the wind turbine control switching device of the present invention; Figure 2 This is a schematic diagram of the interface structure of the fan of the present invention; Figure 3 This is a schematic diagram showing the connection between the fan control switching device of the present invention and the fan and environmental controller; Figure 4 This is a schematic diagram of the circuit structure of the fan control switching device of the present invention; Figure 5 This is a circuit diagram of the communication circuit of the present invention; Figure 6 This is a circuit diagram showing the connection between the first protection circuit and the second protection circuit of the present invention. Figure 7 This is a circuit diagram of the logic circuit of the present invention; Figure 8 This is a circuit diagram of the DI control circuit of the present invention; Figure 9 This is a circuit diagram of the third protection circuit of the present invention; Figure 10 This is a control logic diagram of the fan control switching device of the present invention; Figure 11 This is a schematic diagram of the physical connection of the fan control switching device of the present invention. Detailed Implementation

[0022] 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 a part of the embodiments of the present invention, and not all of them. 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.

[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0024] like Figure 1 , Figure 3 and Figure 4 As shown, this embodiment provides a fan control switching device, including a housing, and a control circuit board is provided inside the housing; The control circuit board integrates logic circuits and a built-in power supply. The control circuit board also includes a gear control circuit, a communication circuit, and a wireless communication module, which are respectively connected to the logic circuit. The wireless communication module is used to establish a wireless communication connection with an external mobile terminal. The outer casing is provided with a first digital communication interface, a second digital communication interface, a gear control interface, and a power input interface; the communication circuit is connected to the environmental controller via the first digital communication interface; the communication circuit is also connected to the fan via the second digital communication interface; the gear control interface has multiple gear control switches; the gear control circuit is connected to the control switches of the power supply box via the multiple gear control switches respectively. More specifically, the plurality of gear control switches correspond to different speed gears of the fan; The power supply box is connected to the fan via an analog voltage control line, and the power supply box is used to send analog voltage signals to the fan. More specifically, the power supply box sends an analog voltage signal of 0~10V to the fan; When all the gear control switches are in the off state, the logic circuit enables the first and second digital communication interfaces. At this time, a digital communication link is established between the environmental controller and the fan for transmitting digital signals. When at least one gear control switch is in the short ground wire state, the logic circuit shields the first and second digital communication interfaces. At this time, the environmental controller establishes an analog communication link between the power supply box and the fan for transmitting analog voltage signals. The gear control circuit is electrically connected to the built-in power supply, and the built-in power supply is electrically connected to the fan through the power input interface.

[0025] like Figure 4-5 As shown, the communication circuit includes a 485 chip circuit and a first protection circuit; The 485 chip circuit includes chip U2 and chip U3; the first protection circuit is connected to chip U2 and chip U3 respectively through a 485B2-in interface; the 485B2 interface of the first protection circuit forms the first digital communication interface; chip U3 is also connected to the logic circuit through a DE1 interface, a UART-RX interface, and a UART-TX interface; chip U2 is also connected to the logic circuit through a DE2 interface, a UART-RX interface, and a UART-TX interface; chip U2 is connected to chip U3 respectively through UART-RX and UART-TX interfaces. Preferably, both chip U2 and chip U3 are RS485 chips; More specifically, pin R of chip U3 is connected to resistor R12 and capacitor C14 respectively, and the other end of capacitor C14 is grounded; resistor R12 is then connected to the UART-RX interface; pin RE and pin DE of chip U3 are simultaneously connected to resistor R19, resistor R19 is connected to capacitor C15, and the other end of capacitor C15 is grounded. More specifically, pin R of chip U2 is connected to resistor R11 and capacitor C12 respectively, with the other end of capacitor C12 grounded; resistor R11 is connected in series with resistor R7, resistor R8, and UART-RX interface in sequence; pin D of chip U2 is connected to the UART-RX interface; resistor R11 is also connected to the UART-TX interface of chip U3; pins RE and DE of chip U2 are simultaneously connected to resistor R18, resistor R18 is connected to capacitor C13, with the other end of capacitor C13 grounded. like Figure 6 As shown, the first protection circuit includes a resistor R17, a current-limiting resistor R5, and bidirectional breakdown diodes D13 and D14; one end of the bidirectional breakdown diode D13 is connected to the resistor R17 and the bidirectional breakdown diode D14 respectively, and the other end is grounded; the other end of the resistor R17 is connected to the 485B2 interface; one end of the bidirectional breakdown diode D14 is connected to the current-limiting resistor R5 and the 485B2-in interface in sequence.

[0026] Specifically, the communication circuit further includes a second protection circuit; the second protection circuit is connected to chip U3 and chip U2 respectively through a 485A2-in interface; the 485A2 interface of the second protection circuit forms the second digital communication interface; The second protection circuit includes a resistor R20, a current-limiting resistor R21, and a bidirectional breakdown diode D16; the other end of the bidirectional breakdown diode D14 is connected to the resistor R20, the bidirectional breakdown diode D16, and the current-limiting resistor R21 respectively; the resistor R20 is then connected to the 485A2 interface; the current-limiting resistor R21 is then connected to the 485A2-in interface; the other end of the bidirectional breakdown diode D16 is grounded. Preferably, resistors R17 and R20 are PTC thermistors, model nSMD010; bidirectional breakdown diodes D13, D14, and D16 are all model SMBJ6.5CA; and current-limiting resistors R5 and R21 have a resistance of 10Ω. More specifically, the PTC thermistor and bidirectional breakdown diode are a combination of a PTC resettable fuse and a bidirectional TVS transient diode, used to control the incoming current and voltage clamping. Preferably, both chip U2 and chip U3 are RS485 chips, the model of which is SP485EEN, and the two RS485 chips are designed back to back; capacitors C12 to C15 are all filter capacitors; resistors R7 and R8 are pull-up resistors; resistors R11, R12, R18, and R19 are all current-limiting resistors.

[0027] like Figure 7As shown, the logic circuit includes an inverter U4, whose UART-RX and UART-TX interfaces are connected to the chip U2 and chip U3 respectively; the DE1 interface of the inverter U4 is connected to the chip U3; and the DE2 interface of the inverter U4 is connected to the chip U2. The logic circuit also includes diodes D15 and D18, resistors R23 and R27, and capacitors C9 and C11; wherein, one end of resistor R23 is connected to the 1A interface of inverter U4 and capacitor C9 respectively, and the other end of resistor R23 is connected to the UART-RX interface; diode D15 is connected in parallel across resistor R23. One end of resistor R27 is connected to the 2A interface of inverter U4 and capacitor C11 respectively, and the other end of resistor R27 is connected to UART-TX interface; diode D18 is connected in parallel across resistor R27; capacitor C9 is connected in series with capacitor C11. More specifically, resistor R23 and capacitor C9 form the first RC filter; resistor R27 and capacitor C11 form the second RC filter; More specifically, the inverter U4 is model SN74LVC2G14; diodes D15 and D18 are both Schottky diodes, model B5817.

[0028] like Figure 8 As shown, the gear control circuit includes a DI control circuit and a third protection circuit. The DI control circuit is connected to the plurality of gear control switches through the third protection circuit. The DI control circuit is also connected to the built-in power supply and logic circuit respectively. like Figure 9 As shown, the third protection circuit includes diode D19 and Zener diode D20, with Zener diode D20 being an SMBJ6.5 type. The negative terminal of Zener diode D20 is connected to the negative terminal of diode D19, and the positive terminal of Zener diode D20 is grounded. One port of the DI1 level line is connected between transient suppression diode D2 and diode D19. More specifically, the DI control circuit includes transistors Q2, Q4, Q5, and Q7, diodes D3 and D7, and a Zener diode D10; the cathode of the Zener diode D10 is connected to the cathodes of diodes D3 and D7 respectively, and the anode of the Zener diode D10 is grounded; one port of the DI2 level line is connected between diodes D3 and D10; The DI control circuit also includes bias resistors R1, R4, R25, R26, R30, and R31, and a pull-down resistor R28. The two ends of the pull-down resistor R28 are connected in parallel to the collector and emitter of transistor Q5, with the emitter grounded. The base of transistor Q5 is connected to the bias resistor R25 and the collector of transistor Q7, respectively. The emitter of transistor Q5 is connected to the DE1 and DE2 interfaces in the logic circuit via the DEx interface. The emitter of transistor Q7 is grounded, and the base of transistor Q7 is connected to the bias resistor R31. The two ends of the bias resistor R26 are connected in parallel to the collector and emitter of transistor Q5, respectively. The bias resistors R25 and R31 are connected; the bias resistor R31 is connected to the anode of the diode D19; the bias resistor R26 is connected to the anode of the diode D3; the two ends of the bias resistor R1 are connected in parallel with the collector and base of the transistor Q2, respectively, and the emitter of the transistor Q2 is electrically connected to the built-in power supply for inputting a 0-10V voltage; the collector of the transistor Q4 is connected to the base of the transistor Q2, and the base of the transistor Q4 is connected in sequence to the bias resistors R4 and R30, and the bias resistor R30 is also connected to the anode of the diode D7; the emitter of the transistor Q4 is grounded. Preferably, transistors Q2, Q4, Q5, and Q7 are all MMBT5551. Preferably, diodes D3, D7, and D19 are all of type B5819.

[0029] like Figure 10 As shown, the plurality of gear control switches include switches DI1 to DI4; when switch DI1 is short-grounded, the output analog voltage signal is defined by the power supply box; when any one of switches DI2 to DI4 is short-grounded, it is used to output different preset voltage signals inside the logic circuit respectively.

[0030] Specifically, when switches DI1 to DI4 are simultaneously short-grounded, the control logic corresponding to the highest priority gear control switch is executed in ascending order of priority from switch DI1 to switch DI4.

[0031] Specifically, the wireless communication module is a Bluetooth module with serial port functionality. The Bluetooth module is configured to establish a point-to-point wireless communication connection with the external mobile terminal. In this embodiment, data transmission does not require a server. After the Bluetooth module receives data from the external mobile terminal, the logic circuit sends it to the wind turbine through the second digital communication interface. After the wind turbine sends data through the second digital communication interface, the logic circuit sends it to the external mobile terminal through the Bluetooth module. More specifically, the external mobile terminal is a mobile app, which is used to receive data from the Bluetooth module and to send data to the Bluetooth module; More specifically, chip U2 is connected to chip U3 via UART-RX and UART-TX interfaces respectively, forming a serial port connection between two RS485 chips; the Bluetooth module is connected to UART-RX and UART-TX interfaces respectively, so that the Bluetooth module is connected in parallel in the serial port signals of the two RS485 chips. More specifically, the Bluetooth module requires a key to connect to the mobile app, ensuring a private connection.

[0032] This embodiment also provides a ventilation control system, including an environmental controller and a fan, as well as the aforementioned fan control switching device; The first digital communication interface of the wind turbine control switching device is connected to the environmental controller, and the second digital communication interface of the wind turbine control switching device is connected to the wind turbine.

[0033] This embodiment also provides a fan switching control method, applied to the above-mentioned ventilation control system, the method comprising the following steps: Step S1: Pre-set one of the gear control switches as the first gear control switch, and the remaining gear control switches as the second, third, and fourth gear control switches respectively; the fan control switching device internally presets different voltage values ​​corresponding to different gear control switches, and different gear control switches correspond to different speed gears of the fan; the logic circuit monitors whether each gear control switch is in the open state or the short ground wire state; Step S2: Digital mode execution; if all gear control switches are not short-circuited to the ground wire, a digital communication link is established between the environmental controller and the fan, and the environmental controller controls the fan through digital signals; Step S3: Analog mode execution. If any gear control switch is detected to be short-circuited by a ground wire, the digital communication link is interrupted, and analog voltage signal output is initiated. Specifically, the analog mode execution includes: Step S3a: If the short ground wire is the first gear control switch, the power supply box outputs a 0~10V analog voltage signal to the fan; Step S3b: If the short ground wire is the control switch for the second, third, or fourth gear position, the fan control switching device outputs the internal preset voltage value corresponding to the control switch for that gear position, and the fan switches the corresponding speed gear according to the different voltage values.

[0034] It should be noted that in step S3, if multiple gear control switches are detected to be short-grounded at the same time, the control logic corresponding to the gear control switch with the highest priority is executed according to the preset priority order.

[0035] like Figure 2 , Figure 10 and Figure 11 As shown, the fan is an EC710 cylindrical fan (referred to as an EC fan), and the specific operation of the ventilation control system includes: 1) The 10V auxiliary power supply of the EC fan supplies power to the fan control switching device. The fan control switching device achieves low power consumption, requiring only a 10V, 6m power supply. The fan control switching device is connected to the power supply box through DI1~DI4 switches. The power supply box is connected to the EC fan through 0~10V analog voltage control lines. 2) When the DI1 switch is short-circuited to the ground wire, the communication of the digital communication link can be blocked. The user can use the 0-10V analog voltage signal to adjust the speed of the EC fan through the power supply box. The 0-10V speed adjustment voltage is defined by the user. 3) When any one of the DI2~DI4 switches is short-circuited to the ground wire, the communication of the digital communication link is blocked, and the speed regulation is achieved by using 0-10V analog voltage. The speed regulation voltage is supplied to the EC fan according to the voltage set inside the fan control switching equipment. The DI2~DI4 switches output different analog voltages to realize the multi-speed regulation of the EC fan. 4) When switches DI1 to DI4 are shorted to ground at the same time, the execution priority is increased from DI1 to DI4. 5) When all switches DI1 to DI4 are disconnected from the ground wire, the communication of the digital communication link is restored; 6) The fan control switching device has a Bluetooth module. The mobile APP connects to the Bluetooth module, and the user can send information to the EC fan from the mobile APP and read the return information from the EC fan. When the mobile APP sends or receives information, switches DI1~DI4 must be disconnected from the ground wire. In addition, the user can read the communication data between the environmental controller and the EC fan in the APP, and the data can be used for testing. Furthermore, the APP can be used to set the EC cylindrical fan (such as address change, fan control mode change, etc.).

[0036] First, in terms of the components used, traditional switching tools have more and more complex components than the fan control switching device described in this embodiment. The fan control switching device only uses simple resistors, capacitors, RS485 chips, logic circuits, and Bluetooth modules, and its cost is much lower than that of traditional switching tools. Secondly, this embodiment does not require the use of a microcontroller. The digital signal of the fan control switching device described in this embodiment is directly connected to the EC fan, realizing direct transmission of digital signals and faster signal transmission speed. Moreover, this embodiment only requires a free Bluetooth connection and can achieve wireless communication without a server. Bluetooth's point-to-point anti-interference signal is stronger and data transmission is more reliable. Although this embodiment has certain wireless distance requirements, there is no need to worry about network attacks, and it can be used stably and reliably within the area. Finally, the multi-position control switches of the aforementioned wind turbine control switching device are directly led out, and the user leads all the position control switches to the user's power supply box. This is equivalent to the wind turbine control switching device being directly installed on the power supply box, using far less wiring than traditional methods. Moreover, in practical applications, the wind turbine control switching device described in this embodiment only costs tens of RMB, which can effectively protect expensive EC wind turbines and environmental controllers, greatly reducing maintenance and debugging costs for users. Therefore, this embodiment has the advantages of easy maintenance and lower overall cost.

[0037] Based on the disclosure and teachings of the foregoing specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on the present invention.

Claims

1. A fan control switching device, characterized in that, It includes an outer casing, and a control circuit board is disposed inside the outer casing; The control circuit board integrates logic circuits and a built-in power supply. The control circuit board also includes a gear control circuit, a communication circuit, and a wireless communication module, which are respectively connected to the logic circuit. The wireless communication module is used to establish a wireless communication connection with an external mobile terminal. The outer casing is provided with a first digital communication interface, a second digital communication interface, a gear control interface, and a power input interface; the communication circuit is connected to the environmental controller via the first digital communication interface; the communication circuit is also connected to the fan via the second digital communication interface; the gear control interface has multiple gear control switches; the gear control circuit is connected to the control switches of the power supply box via the multiple gear control switches respectively. The power supply box is connected to the fan via an analog voltage control line, and the power supply box is used to send analog voltage signals to the fan. When all the gear control switches are in the off state, the logic circuit enables the first and second digital communication interfaces. At this time, a digital communication link is established between the environmental controller and the fan for transmitting digital signals. When at least one gear control switch is in the short ground wire state, the logic circuit shields the first and second digital communication interfaces. At this time, the environmental controller establishes an analog communication link between the power supply box and the fan for transmitting analog voltage signals. The gear control circuit is electrically connected to the built-in power supply, and the built-in power supply is electrically connected to the fan through the power input interface.

2. The fan control switching device according to claim 1, characterized in that, The communication circuit includes a 485 chip circuit and a first protection circuit; The 485 chip circuit includes chip U2 and chip U3; the first protection circuit is connected to chip U2 and chip U3 respectively through a 485B2-in interface; the 485B2 interface of the first protection circuit forms the first digital communication interface; chip U3 is also connected to the logic circuit through a DE1 interface, a UART-RX interface and a UART-TX interface; chip U2 is also connected to the logic circuit through a DE2 interface, a UART-RX interface and a UART-TX interface; chip U2 is connected to chip U3 respectively through UART-RX and UART-TX interfaces.

3. The fan control switching device according to claim 2, characterized in that, The communication circuit also includes a second protection circuit; the second protection circuit is connected to chip U3 and chip U2 respectively through a 485A2-in interface; the 485A2 interface of the second protection circuit forms the second digital communication interface.

4. The fan control switching device according to claim 3, characterized in that, The logic circuit includes an inverter U4, whose UART-RX and UART-TX interfaces are connected to the chip U2 and chip U3 respectively; the DE1 interface of the inverter U4 is connected to the chip U3; and the DE2 interface of the inverter U4 is connected to the chip U2. The logic circuit also includes diodes D15 and D18, resistors R23 and R27, and capacitors C9 and C11; wherein, one end of resistor R23 is connected to the 1A interface of inverter U4 and capacitor C9 respectively, and the other end of resistor R23 is connected to the UART-RX interface; diode D15 is connected in parallel across resistor R23. One end of resistor R27 is connected to the 2A interface of inverter U4 and capacitor C11 respectively, and the other end of resistor R27 is connected to UART-TX interface; diode D18 is connected in parallel across resistor R27; capacitor C9 is connected in series with capacitor C11.

5. The fan control switching device according to claim 1, characterized in that, The gear control circuit includes a DI control circuit and a third protection circuit. The DI control circuit is connected to the plurality of gear control switches through the third protection circuit. The DI control circuit is also connected to the built-in power supply and logic circuit respectively.

6. The fan control switching device according to claim 5, characterized in that, The plurality of gear control switches include switches DI1 to DI4; when switch DI1 is short-grounded, the output analog voltage signal is defined by the power supply box; when any one of switches DI2 to DI4 is short-grounded, it is used to output different preset voltage signals inside the logic circuit respectively.

7. The fan control switching device according to claim 6, characterized in that, When switches DI1 to DI4 are simultaneously short-grounded, the control logic corresponding to the highest priority gear control switch is executed in ascending order of priority from switch DI1 to switch DI4.

8. The fan control switching device according to claim 1, characterized in that, The wireless communication module is a Bluetooth module, which is configured to establish a point-to-point wireless communication connection with the external mobile terminal. After the Bluetooth module receives data from the external mobile terminal, the logic circuit sends it to the wind turbine through the second digital communication interface. After the wind turbine sends data through the second digital communication interface, the logic circuit sends it to the external mobile terminal through the Bluetooth module.

9. A ventilation control system, comprising an environmental controller and a fan, characterized in that, It also includes a fan control switching device as described in any one of claims 1-8; The first digital communication interface of the wind turbine control switching device is connected to the environmental controller, and the second digital communication interface of the wind turbine control switching device is connected to the wind turbine.

10. A fan switching control method, characterized in that, The method, applied to a ventilation control system as described in claim 9, includes the following steps: Step S1: Pre-set one of the gear control switches as the first gear control switch, and the remaining gear control switches as the second, third, and fourth gear control switches respectively; the fan control switching device internally presets different voltage values ​​corresponding to different gear control switches, and different gear control switches correspond to different speed gears of the fan; the logic circuit monitors whether each gear control switch is in the open state or the short ground wire state; Step S2: Digital mode execution; if all gear control switches are not short-circuited to the ground wire, a digital communication link is established between the environmental controller and the fan, and the environmental controller controls the fan through digital signals; Step S3: Analog mode execution. If any gear control switch is detected to be short-circuited by a ground wire, the digital communication link is interrupted, and analog voltage signal output is initiated. Specifically, the analog mode execution includes: Step S3a: If the short ground wire is the first gear control switch, the power supply box outputs a 0~10V analog voltage signal to the fan; Step S3b: If the short ground wire is the control switch for the second, third, or fourth gear position, the fan control switching device outputs the internal preset voltage value corresponding to the control switch for that gear position, and the fan switches the corresponding speed gear according to the different voltage values.

Images