Control circuit of air valve

Abstract

The utility model provides a control circuit of an air valve, which comprises a power supply circuit, a motor positive and negative rotation limit circuit, a motor driving circuit, a controller, a signal isolation circuit, a communication circuit and an output circuit, the power supply circuit respectively supplies power to the motor driving circuit and the controller, and the motor positive and negative rotation limit circuit is connected with the motor driving circuit. The controller is respectively connected with the motor driving circuit, the signal isolation circuit, the communication circuit and the output circuit, and the output circuit is also connected with the motor driving circuit. Therefore, synchronous output can be realized through the output circuit and the communication circuit, display of each fault code during multiple faults can be ensured, and positive and negative rotation limiting of the motor is realized through the two microswitches.

Description

Technical Field

[0001] This utility model relates to the field of air valve technology, specifically to a control circuit for an air valve. Background Technology

[0002] Air dampers are indispensable components used in ventilation, air conditioning, and air purification projects in various buildings, controlling the airflow. Regarding air damper control, prior art patent application CN201910214906.6 discloses a control circuit board for air dampers in a ventilation and air conditioning system. This solution employs a PIC controller, one analog circuit, two analog circuits, a digital signal isolation circuit, a reset self-test circuit, a signal isolation circuit, a passive digital output circuit, an active digital output circuit, and a drive output circuit.

[0003] When the air valve is controlled by the above method, and the air valve has many different types of faults, the host computer cannot continue to identify them, resulting in the inability to display multiple fault codes. Utility Model Content

[0004] To solve one of the aforementioned technical problems, this utility model proposes the following technical solution.

[0005] The first aspect of this utility model provides a control circuit for a damper, including a power supply circuit, a motor forward and reverse rotation limit circuit, a motor drive circuit, a controller, a signal isolation circuit, a communication circuit, and an output circuit. The power supply circuit supplies power to the motor drive circuit and the controller. The motor forward and reverse rotation limit circuit is connected to the motor drive circuit. The controller is connected to the motor drive circuit, the signal isolation circuit, the communication circuit, and the output circuit. The output circuit is also connected to the motor drive circuit.

[0006] The motor forward and reverse rotation limit circuit includes a first micro switch and a second micro switch respectively installed at the front and rear ends of the motor. One end of the first micro switch and one end of the second micro switch are respectively connected to a common terminal. The common terminal is respectively connected to the motor drive circuit and the signal isolation circuit. The other end of the first micro switch and the other end of the second micro switch are respectively connected to the motor drive circuit.

[0007] In addition, the control circuit of the air valve according to the above embodiments of the present invention may also have the following additional technical features.

[0008] In some examples, the power supply circuit includes a power input protection circuit, a first capacitor, a first power conversion circuit, a second capacitor, a second power conversion circuit, and a third capacitor. The power input protection circuit includes a TVS diode and a first diode.

[0009] In this circuit, the two ends of the TVS diode are connected to the positive and negative terminals of the power supply, respectively. The anode of the first diode is connected to the positive terminal of the power supply. The cathode of the first diode and one end of the first capacitor are connected to the first terminal of the first power conversion circuit. The negative terminal of the power supply and the other end of the first capacitor are connected to the second terminal of the first power conversion circuit. The third terminal of the first power conversion circuit and one end of the second capacitor are connected to the first terminal of the second power conversion circuit. The fourth terminal of the first power conversion circuit and the other end of the second capacitor are connected to the second terminal of the second power conversion circuit. The fifth terminal of the first power conversion circuit is connected to the motor drive circuit. The third and fourth terminals of the second power conversion circuit are connected to one end and the other end of the third capacitor, respectively. The fifth terminal of the second power conversion circuit is connected to the controller.

[0010] In some examples, the signal isolation circuit includes a second diode, a resistor, and an optocoupler. The anode of the second diode is connected to the positive terminal of the power supply, the cathode of the second diode is connected to the positive terminal of the primary side of the optocoupler through the resistor, the negative terminal of the primary side of the optocoupler is connected to the signal input terminal, and the secondary side of the optocoupler is connected to the controller.

[0011] In some examples, the communication circuit includes a level shifter and a communication protection circuit, with the controller, the level shifter, and the communication protection circuit connected in sequence.

[0012] In some examples, a third diode is connected between the output circuit and the motor drive circuit, and the output circuit includes a relay.

[0013] In some examples, the motor drive circuit includes a signal amplification circuit.

[0014] The technical solution of this utility model embodiment can achieve synchronous output through the output circuit and the communication circuit, which can ensure the display of each fault code when there are multiple faults, and realize the forward and reverse rotation limit of the motor through two micro switches. Attached Figure Description

[0015] Figure 1 This is a structural block diagram of the control circuit of the air valve according to one embodiment of the present invention.

[0016] Figure 2 This is a schematic diagram of the structure of a motor drive circuit as an example of this utility model.

[0017] Figure 3 This is a schematic diagram of the power supply circuit of an example of this utility model.

[0018] Figure 4This is a schematic diagram of a signal isolation circuit as an example of this utility model.

[0019] Figure 5 This is a schematic diagram of the structure of a communication circuit as an example of this utility model.

[0020] Figure 6 This is a schematic diagram of the output circuit of an example of this utility model.

[0021] Figure 7 This is a schematic diagram of the structure of a motor drive circuit as an example of this utility model. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] The existing technology has the following defects or shortcomings:

[0024] The control circuit board lacks communication transmission functionality, and the use of switch output signals cannot meet the display requirements of the diverse range of fault codes; the power input uses AC 220V, resulting in poor grid compatibility; the switch signal input lacks reverse connection protection; and the drive output circuit, using switch signals, cannot detect the valve opening direction.

[0025] Therefore, this utility model embodiment proposes a control circuit for a wind valve.

[0026] Figure 1 This is a structural block diagram of the control circuit of the air valve according to one embodiment of the present invention.

[0027] like Figure 1 As shown, the control circuit of the air valve includes a power supply circuit 1, a motor forward and reverse rotation limit circuit 2, a motor drive circuit 3, a controller 4, a signal isolation circuit 5, a communication circuit 6, and an output circuit 7. The power supply circuit 1 supplies power to the motor drive circuit 3 and the controller 4 respectively. The motor forward and reverse rotation limit circuit 2 is connected to the motor drive circuit 3. The controller 4 is connected to the motor drive circuit 3, the signal isolation circuit 5, the communication circuit 6, and the output circuit 7 respectively. The communication circuit 6 and the output circuit are connected to external devices respectively. The output circuit 7 is also connected to the motor drive circuit 3.

[0028] like Figure 2As shown, the motor forward and reverse rotation limit circuit 2 includes a first micro switch LS1 and a second micro switch LS2 respectively installed at the front and rear ends of the motor (not shown in the figure). One end of the first micro switch LS1 and one end of the second micro switch LS2 are respectively connected to a common terminal. The common terminal is connected to the motor drive circuit 3 and the signal isolation circuit 5 respectively. Figure 2 (Not shown in the diagram) The other end of the first micro switch LS1 and the other end of the second micro switch LS2 are respectively connected to the motor drive circuit 3.

[0029] Specifically, the opening, closing, and opening angle of the air valve are controlled by a motor. The motor is mounted on the blades, and two microswitches are installed at the maximum and minimum rotation positions of the motor, respectively. The air valve and the motor work together through the blades. The motor drives the blades to rotate, and the blades drive the air valve to move.

[0030] Control Relationship: The opening signal is controlled by an external input signal. Under the control of the controller, the motor rotates forward and the blades move simultaneously. When the set angle is reached, the rotation stops and the air valve remains open at a certain angle. If the forward rotation limit is encountered during the process, the machine stops and a fault is reported. The closing signal is controlled by an external input signal. Under the control of the controller, the motor rotates in reverse. When the fully closed angle is reached, the rotation stops and the entire air valve vent is closed. If the reverse rotation limit is encountered during the process, the machine stops and a fault is reported.

[0031] Hard limit switches LS1 and LS2, installed at the front and rear ends of the motor, are used to achieve forward and reverse motor control. When the motor loses control, the microswitches can provide feedback that the motor has exceeded the hard limit. The positive and negative limit signals are input to the drive signal and then enter the controller 4. Function: When the positive limit switch LS1 forms a loop with the common terminal, the output of the motor drive signal 3 changes from low to high and is sent to GPIO (General Purpose I / O Ports) 1. The controller 4 receives the level change and determines the program strategy. When the negative limit switch LS2 forms a loop with the common terminal, the output of the motor drive signal 3 changes from low to high and is sent to GPIO 2. The controller 4 receives the level change and determines the program strategy.

[0032] The aforementioned control circuit enables the drive control of the motor, thereby controlling the air valve. During the control process, the motor's forward and reverse rotation is limited, and it also has a communication transmission function. The output signal is synchronously output to an external device, such as a host computer, through the output circuit and communication circuit, and the fault code is displayed through the external device. Therefore, when multiple faults occur in the air valve, it can be ensured that the host computer can identify each fault code.

[0033] Therefore, synchronous output can be achieved through the output circuit and communication circuit, which can ensure the display of each fault code when there are multiple faults, and the forward and reverse rotation limits of the motor can be achieved through two micro switches.

[0034] In one example, such as Figure 3 As shown, the power supply circuit 1 includes a power input protection circuit 11, a first capacitor C1, a first power conversion circuit 12, a second capacitor C2, a second power conversion circuit 13, and a third capacitor C3. The power input protection circuit 11 includes a TVS diode D2 and a first diode D1.

[0035] In this circuit, the two ends of TVS diode D2 are connected to the positive and negative terminals of the power supply, respectively. The anode of the first diode D1 is connected to the positive terminal of the power supply. The cathode of the first diode D1 and one end of the first capacitor C1 are connected to the first terminal of the first power conversion circuit 12. The negative terminal of the power supply and the other end of the first capacitor C1 are connected to the second terminal of the first power conversion circuit 12. The third terminal of the first power conversion circuit 12 and one end of the second capacitor C2 are connected to the first terminal of the second power conversion circuit 13. The fourth terminal of the first power conversion circuit 12 and the other end of the second capacitor C2 are connected to the second terminal of the second power conversion circuit 13. The fifth terminal of the first power conversion circuit 12 is connected to the motor drive circuit 3. The third and fourth terminals of the second power conversion circuit 13 are connected to one end and the other end of the third capacitor C3, respectively. The fifth terminal of the second power conversion circuit 13 is connected to the controller 4.

[0036] Specifically, the power input protection circuit 11 can prevent reverse connection and overvoltage issues. The input voltage adopts a wide voltage range of 27V to 15V, which can meet most 24V DC voltage scenarios. Functions: the first diode D1 prevents reverse connection of the circuit power supply and can prevent current from flowing in reverse; the TVS diode D2 plays the role of overvoltage protection in the input voltage protection. When the input voltage exceeds the threshold, the current will bypass the current flowing through the D2 device; C1, C2, and C3 are used for voltage support and filtering; in this circuit, the external power input of 24V can be converted into 12V to supply the motor drive circuit 3, and then further converted into 3.3V to supply the controller 4.

[0037] Therefore, the input has reverse connection protection and the power supply uses DC voltage, which can meet most needs and has wide adaptability.

[0038] In one example, such as Figure 4 As shown, the signal isolation circuit 5 includes a second diode D4, a resistor R2, and an optocoupler U1. The anode of the second diode D4 is connected to the positive terminal of the power supply, and the cathode of the second diode D4 is connected to the positive terminal of the primary side of the optocoupler U1 through the resistor R2. The negative terminal of the primary side of the optocoupler U1 is connected to the signal input terminal, and the secondary side of the optocoupler U1 is connected to the controller 4.

[0039] Specifically, externally, only passive contacts are needed to connect the signal input terminal and the signal common terminal. When the external connection is incorrect, the reverse connection protection diode, the second diode D4, will prevent current from flowing. Function: The primary side of U1 is a light-emitting diode. The external circuit generates a 24V forward circuit to make the light-emitting diode conduct and light up. The secondary side transistor of U1 conducts, shorting GPIO (General Purpose I / O Ports) and GND, pulling down the potential of pin 4 of the controller.

[0040] Therefore, an input signal with a voltage source is used to avoid incorrect voltage connection when inputting the signal.

[0041] In one example, such as Figure 5 As shown, the communication circuit 6 includes a level converter 61 and a communication protection circuit 62. The controller 4, the level converter 61 and the communication protection circuit 62 are connected in sequence.

[0042] Specifically, refer to Figure 5 Communication A and Communication B are connected to the host computer or other devices. The USART Rx (receive data input pin of Universal Synchronous / Asynchronous Receiver / Transmitter), USART Tx (transmit pin of Universal Synchronous / Asynchronous Receiver / Transmitter), and REDE pin (control pin for controlling data transmission and reception) are connected to the controller 4. The main function of the level converter 61 is to convert TTL level to 485 differential signal. After being programmed, the controller 4 outputs fault codes and data information. According to the communication protocol, other peripheral devices can obtain the current device status and detailed fault parameters.

[0043] In one example, such as Figure 6 As shown, a third diode D3 is connected between the output circuit 7 and the motor drive circuit 3. The output circuit 7 includes a relay.

[0044] Specifically, the positive and negative output signals form a set of passive dry contact outputs. Considering compatibility with external signals, the passive dry contacts do not require consideration of pull-up / pull-down states. The output dry contacts are completely isolated from the internal power supply, with no electrical signal connection. The motor drive circuit 3 uses a small current to amplify the signal before controlling the output circuit. The signal output source is the controller 4. Function: After the controller 4 outputs a high level to the motor drive circuit 3, the motor drive circuit 3 amplifies the signal and pulls the OUT3 signal low, causing the relay coil in its output circuit to generate a 12V power supply loop. After the relay coil is energized, the normally open contact S closes, connecting the external output signal + and the external output signal -.

[0045] In one example, such as Figure 7 As shown, the motor drive circuit 3 includes a signal amplification circuit. The signal amplification circuit can amplify the signal using two transistors.

[0046] Specifically, the controller 4 sends pulse signals, which are amplified by the signal amplification circuit to control the rotation of the motor. After multiple pulses are sent, the motor rotates by a certain number of degrees. The speed and angle of the motor are adjusted by the strategy and algorithm of the controller 4. The motor has 5 pins, which are connected to a 12V positive power supply. Phases A, B, C and D are connected to the motor drive circuit 3.

[0047] Therefore, the motor drive uses a pulse method to calculate the angular displacement and provide feedback on the actual angle, thereby detecting the valve opening and turning position.

[0048] In summary, this utility model embodiment enables multi-angle adjustment of the motor, linkage fire control with the BMS of the energy storage battery compartment, real-time reporting of fault and operation information of the adjustable device, and control of the fan to open or close via dry contacts. It also retains the function of outputting dry contacts to output dry contact signals when there is no communication or a communication failure.

[0049] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A control circuit for an air valve, characterized in that, The system includes a power supply circuit, a motor forward / reverse limit circuit, a motor drive circuit, a controller, a signal isolation circuit, a communication circuit, and an output circuit. The power supply circuit supplies power to both the motor drive circuit and the controller. The motor forward / reverse limit circuit is connected to the motor drive circuit. The controller is connected to the motor drive circuit, the signal isolation circuit, the communication circuit, and the output circuit. The output circuit is also connected to the motor drive circuit. The motor forward and reverse rotation limit circuit includes a first micro switch and a second micro switch respectively installed at the front and rear ends of the motor. One end of the first micro switch and one end of the second micro switch are respectively connected to a common terminal. The common terminal is respectively connected to the motor drive circuit and the signal isolation circuit. The other end of the first micro switch and the other end of the second micro switch are respectively connected to the motor drive circuit.

2. The control circuit for the air valve according to claim 1, characterized in that, The power supply circuit includes a power input protection circuit, a first capacitor, a first power conversion circuit, a second capacitor, a second power conversion circuit, and a third capacitor. The power input protection circuit includes a TVS diode and a first diode. In this circuit, the two ends of the TVS diode are connected to the positive and negative terminals of the power supply, respectively. The anode of the first diode is connected to the positive terminal of the power supply. The cathode of the first diode and one end of the first capacitor are connected to the first terminal of the first power conversion circuit. The negative terminal of the power supply and the other end of the first capacitor are connected to the second terminal of the first power conversion circuit. The third terminal of the first power conversion circuit and one end of the second capacitor are connected to the first terminal of the second power conversion circuit. The fourth terminal of the first power conversion circuit and the other end of the second capacitor are connected to the second terminal of the second power conversion circuit. The fifth terminal of the first power conversion circuit is connected to the motor drive circuit. The third and fourth terminals of the second power conversion circuit are connected to one end and the other end of the third capacitor, respectively. The fifth terminal of the second power conversion circuit is connected to the controller.

3. The control circuit for the air valve according to claim 2, characterized in that, The signal isolation circuit includes a second diode, a resistor, and an optocoupler. The anode of the second diode is connected to the positive terminal of the power supply, and the cathode of the second diode is connected to the positive terminal of the primary side of the optocoupler through the resistor. The negative terminal of the primary side of the optocoupler is connected to the signal input terminal, and the secondary side of the optocoupler is connected to the controller.

4. The control circuit for the air valve according to claim 1, characterized in that, The communication circuit includes a level converter and a communication protection circuit, and the controller, the level converter and the communication protection circuit are connected in sequence.

5. The control circuit for the air valve according to claim 1, characterized in that, A third diode is connected between the output circuit and the motor drive circuit, and the output circuit includes a relay.

6. The control circuit for the air valve according to claim 1, characterized in that, The motor drive circuit includes a signal amplification circuit.

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