A ventilation device
By automatically controlling the start and stop of ventilation equipment and the setting of shields through rainwater and humidity detection, the problems of energy waste and rainwater ingress in ventilation equipment are solved, and automatic control and energy-saving protection functions are realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANGHAI KAIDA SECURITY TECH ENG CO LTD
- Filing Date
- 2025-07-02
- Publication Date
- 2026-07-14
AI Technical Summary
Existing ventilation equipment wastes electricity when it is not turned off after use, and fails to automatically close the inlet or outlet when it rains, causing rainwater to enter the room and affect experimental equipment or reagents.
A ventilation device was designed, comprising a fan body, a housing, a rainwater detection circuit, a control circuit, and a baffle mechanism. The device automatically controls the start and stop of the fan and the opening and closing of the baffle through rainwater and humidity detection, ensuring that the power is automatically shut off when no one is present or when it is raining to prevent rainwater from entering the room, and prompting maintenance when the humidity is too high.
It automatically shuts off the power when no one is around or when it rains, preventing rainwater from entering the room, saving energy, and providing timely alerts for excessively humid environments to protect experimental equipment and reagents.
Smart Images
Figure CN224498667U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of ventilation equipment technology, and in particular to a ventilation device. Background Technology
[0002] Ventilation equipment refers to a system that uses motors, fan blades, and other components to inject fresh air into an indoor space through an air inlet and an exhaust outlet, while simultaneously expelling polluted air that does not meet hygiene standards. This ensures that the indoor air meets both hygiene standards and production needs. Facilities that perform this series of tasks in buildings are collectively referred to as ventilation equipment.
[0003] With the development of industrial technology, the function of ventilation equipment has also been improved. For example, the authorized patent of my country with patent number "202020885969.2" and patent name "A new type of ventilation equipment for factory areas" states that "This utility model realizes a new type of ventilation equipment for factory areas through the mutual cooperation of anti-vibration components and ventilation components, which greatly improves the anti-vibration capability of the ventilation equipment for factory areas, effectively avoids the force generated by external vibration from directly acting on the ventilation equipment, ensures the service life of the ventilation equipment, and also makes the ventilation mechanism easy to disassemble, which is convenient for staff to maintain it. It is highly practical and suitable for widespread use." As can be seen from the above, although the patent has achieved its invention purpose, it is limited by its structure and function. Like other ventilation equipment in this field, it also has the following technical disadvantages. (1) When the equipment is used in areas such as laboratories, if the staff does not actively turn off the power switch after use, it will cause energy waste. (2) It does not have good rain protection function when it rains. That is to say, it cannot automatically shut off the working power or close the inlet or outlet when it rains. This will make it easier for rainwater to enter the room, which will have an adverse effect on related experimental equipment or reagents. Utility Model Content
[0004] To overcome the structural drawbacks of existing ventilation equipment as described in the background, this utility model provides a ventilation device that, under the combined action of relevant mechanisms, only powers on the fan body and automatically opens the shielding mechanism to introduce fresh air into the room when there is no rain outside and people are inside. When no one is inside or it is raining outside, the power switch of the fan body is automatically turned off, and the shielding mechanism is closed when it rains. Furthermore, it can proactively prompt staff to perform maintenance when the indoor air humidity threshold exceeds a set value, thus minimizing the risk of rainwater entering the room and excessive indoor air humidity, which could adversely affect related equipment or reagents.
[0005] The technical solution adopted by this utility model to solve its technical problem is:
[0006] A ventilation device includes a fan body, a housing, and further comprises a rainwater detection circuit, a control circuit, a humidity detection circuit, and a baffle mechanism. The housing has a fixing plate at its rear end, and the fan body is fixedly installed inside the housing. The rainwater detection circuit is equipped with at least two metal plates, which are insulated and fixedly installed on the upper part of the housing at a distance from each other. The baffle mechanism includes an electric push rod, multiple baffles, and a connecting plate. One side of each baffle has a shaft, and the other side has a connecting rod. The front end of the housing has two support plates, each with multiple shaft holes. The multiple baffles have multiple shafts on one side and multiple shafts on the other side. The inner sides of multiple connecting rods at the ends are respectively rotatably sleeved in multiple shaft holes of the end support plates. The outer sides of multiple connecting rods of multiple baffle plates are respectively rotatably sleeved in multiple shaft holes of the connecting plate. The electric push rods are vertically distributed and hinged at the upper end to one end of the front outer side of the housing. The lower end of the electric push rods is rotatably sleeved on the outside of the lowest connecting rod. A baffle plate is installed on the upper part of the front end of the housing. The rainwater detection circuit, control circuit, and humidity detection circuit are installed in the component box. The power output terminal of the control circuit is electrically connected to the power input terminal of the electric push rod and the fan body. The signal input terminal of the control circuit is electrically connected to the signal output terminal of the rainwater detection circuit.
[0007] Furthermore, when the push column of the electric push rod is at the upper stop point, the multiple baffles are in a horizontal structure, and when the push column of the electric push rod is at the lower stop point, the multiple baffles are in a vertical structure, and there is a sealed contact between every two baffles.
[0008] Furthermore, the control circuit includes four electrically connected relays and a microwave detection module. The normally closed contact of the first relay is connected to the positive power input terminal of the microwave detection module and the positive power input terminal of the third relay. The normally open contact of the first relay is connected to the positive power input terminal of the second relay. The negative power input terminal and negative control power input terminal of the second relay are connected to the negative power input terminal and negative control power input terminal of the third relay, the negative power input terminal of the fourth relay, and the negative power input terminal of the microwave detection module. The power output terminal of the microwave detection module is connected to the positive power input terminal of the fourth relay. The positive power input terminal and positive control power input terminal of the first relay are connected to the positive control power input terminals of the second and third relays.
[0009] Furthermore, the humidity detection circuit includes a humidity detection module, an adjustable resistor, a transistor, a resistor, and a buzzer, which are electrically connected. The positive power input terminal of the humidity detection module is connected to the positive power input terminal of the buzzer. The output terminal of the humidity detection module is connected to one end of the adjustable resistor, one end of the resistor, and the base of the transistor. The collector of the transistor is connected to the negative power input terminal of the buzzer. The emitter of the transistor is connected to the negative power input terminal of the humidity detection module.
[0010] Furthermore, the rainwater detection circuit includes an electrically connected resistor and a transistor, and is electrically connected to two metal plates, one of which is connected to one end of the resistor, and the other end of the resistor is connected to the base of the transistor.
[0011] Furthermore, the probes of the humidity detection module and the microwave detection module are located outside the front end of the component box.
[0012] The beneficial effects of this utility model are as follows: This new model is mainly used in, but not limited to, laboratories and similar areas. In application, under the coordinated action of the control circuit and rain detection circuit, the fan body will only be powered on and automatically open the shielding mechanism to allow fresh air into the room when there is no rain outside and people are inside. When no one is inside or it is raining outside, the power switch of the fan body will automatically turn off, and the shielding mechanism will close during rain, achieving automatic control and energy saving, and minimizing the entry of rainwater into the room with the flowing air. Under the action of the humidity detection circuit, when the indoor humidity exceeds the threshold for various reasons, it can promptly alert staff to maintenance through a buzzer, minimizing the adverse effects of excessive indoor humidity on related equipment or reagents. In summary, this new model has good application prospects. Attached Figure Description
[0013] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model.
[0015] Figure 2 This is a partial structural schematic diagram of the present invention.
[0016] Figure 3 This is a partially enlarged structural schematic diagram of the present invention.
[0017] Figure 4 This is the circuit diagram of this utility model. Detailed Implementation
[0018] Figure 1 , 2As shown in Figures 3 and 4, a ventilation device includes a power module W1, an axial flow fan body M2, a rectangular hollow shell 1, and a rainwater detection circuit 7. It also includes a control circuit 2, a humidity detection circuit 3, and a baffle mechanism 4. A fixing plate 101 is integrally formed around the rear end of the shell 1, with a fixing hole on each of its four sides (for easy installation on the outer wall of the ventilation opening, etc.). Multiple support rods are fixedly installed in a ring around the middle of the outer side of the fan body M2, and multiple support rods are longitudinally distributed along the front and rear of the fan body M2 and fixedly installed in the middle of the inner side of the shell 1. The rainwater detection circuit is equipped with two copper metal plates T, which are fixedly mounted on a plastic plate with a 3 mm gap between them. The lower end of the plastic plate is fixedly mounted on the outer side of the upper middle part of the housing 1. The shielding plate mechanism includes an electric push rod M1, multiple rectangular shielding plates 41, and a connecting plate 45. A cylindrical shaft 43 is horizontally fixedly mounted on the middle of the right side of the shielding plate 41, and a horizontally fixed "..." is horizontally fixedly mounted on the middle of the left side of the shielding plate 41. "Type" linkage rod 44 (the front right side of linkage rod 44 and the middle left side of baffle plate 41 are horizontally fixed together), and a support plate 102 is vertically fixedly installed on the front left and right sides of the housing 1, respectively. The support plate 102 has multiple shaft holes 103 at equal intervals from top to bottom; multiple shaft rods 43 on the right side of the multiple baffle plates and multiple linkage rods 44 on the left side are respectively rotatably sleeved in the multiple shaft holes 103 of the right and left support plates 102, respectively. The left side of linkage rod 44 is located on the left outer side of the left support plate 102. The connecting plate has multiple shaft holes A451 at equal intervals from top to bottom. The left ends of multiple linkage rods 44 on the left side of the multiple baffle plates are respectively rotatably sleeved in the multiple shaft holes A451 of the connecting plate (the leftmost of multiple linkage rods 44 is located on the left side of the connecting plate and is fixedly installed with a limiting plate with an outer diameter larger than the inner diameter of shaft hole A). The electric push rod M1 is vertically distributed on the upper right side of the cylinder and hinged to the left front of the housing 1. The push column of the electric push rod M1 is located at the lower end, and a connecting block 42 with a shaft hole B is fixedly installed at the lower end of the push column. The shaft hole B of the connecting block 42 is rotatably sleeved on the left outer side of the lowest connecting rod 44 (a limiting plate A with an outer diameter larger than the inner diameter of the shaft hole B is fixedly installed on the left outer side and the connecting rod 44). A baffle plate 5 with a left-right width and front-back length larger than the width of the left and right support plates and the front length of the two support plates is fixedly installed on the upper part of the front end of the housing (to block rainwater and prevent rainwater from directly splashing onto the fan body). The rainwater detection circuit 7, power module W1, control circuit 2, and humidity detection circuit 3 are installed on the circuit board inside the component box 6, which is installed in the middle of the indoor wall. Two sets of this new type are respectively installed on the outside of the indoor air inlet and air outlet by bolts through the fixing plate 101 (the fan body at the air inlet draws in outdoor air, and the fan body at the air outlet discharges indoor air).
[0019] Figure 1 ,2 As shown in Figures 3 and 4, when the push column of the electric push rod M1 is at the upper stop point, the multiple baffles 41 are in a horizontal structure. When the push column of the electric push rod M1 is at the lower stop point, the multiple baffles 41 are in a vertical structure, and their rear ends are close to the inner sides of the front of the two support plates 102. Between each pair of baffles 41, the rear side of the lower front end of the upper support plate 41 is close to the front side of the upper front end of the lower support plate 41. The control circuit includes four relays K1, K2, K3, and K4 connected via circuit board wiring, a microwave detection module W3, the normally closed contact of the first relay K1 connected to the positive power input terminal (pin 1) of the microwave detection module W3, the positive power input terminal of the third relay K3 connected to the normally open contact of the first relay K1 connected to the positive power input terminal of the second relay K2, the negative power input terminal and negative control power input terminal of the second relay K2, the negative power input terminal and negative control power input terminal of the third relay K3, the negative power input terminal of the fourth relay K4 connected to the negative power input terminal (pin 2) of the microwave detection module W3, the power output terminal (pin 3) of the microwave detection module W3 connected to the positive power input terminal of the fourth relay K4, and the positive power input terminal and positive control power input terminal of the first relay K1 connected to the positive control power input terminal of the second relay K2 and the positive control power input terminal of the third relay K3. The humidity detection circuit includes a humidity detection module W4, an adjustable resistor RP1, a transistor Q2, a resistor R1, and a buzzer B1, all connected via circuit board wiring. Pin 1 of the positive power input of the humidity detection module W4 is connected to the positive power input of the buzzer B1. Pin 3 of the humidity detection module W4 is connected to one end of the adjustable resistor RP1. The other end of the adjustable resistor RP1 is connected to one end of the resistor R1 and the base of the transistor Q2. The collector of the transistor Q2 is connected to the negative power input of the buzzer B1. The emitter of the transistor Q2 is connected to pin 2 of the negative power input of the humidity detection module W4 and the other end of the resistor R1. The rain detection circuit includes a resistor R and a transistor Q1, all connected via circuit board wiring, and connected to two metal plates T via wires. One side of one metal plate T is connected to one end of the resistor R, and the other end of the resistor R is connected to the base of the transistor Q1. The probes of the humidity detection module W4 and the microwave detection module W3 are located outside two openings at the front of the component box 6.
[0020] Figure 1 , 2As shown in Figures 3 and 4, the power input terminals 1 and 2 of the power module W1, the two control power input terminals of the relay K4 in the control circuit, and the two poles of the 220V AC power supply are connected by wires. The two normally open contacts of the relay K4 in the control circuit are connected by wires to the two power input terminals of the axial fan body M2. The power output terminals 3 and 4 of the power module W1, the positive and negative control power input terminals of the relay K2 in the control circuit, the power input terminals 1 and 2 of the humidity detection module W4, the other metal plate T side of the power input terminal of the rainwater detection circuit, and the emitter of the transistor Q1 are connected by wires. The two normally open contacts of the relay K2 and the two normally closed contacts of the relay K3 in the control circuit are connected by wires to the positive and negative and negative-positive power input terminals of the electric push rod M1. The negative power input terminal of the relay K1 in the control circuit and the collector of the transistor Q1 in the signal output terminal of the rainwater detection circuit are connected by wires.
[0021] Figure 1 , 2As shown in Figures 3 and 4, after the 220V AC power enters the power input terminal of the power module W1, the power output terminals 3 and 4 of the power module W1 output a stable 24V DC power, which enters the power input terminals of the control circuit, humidity detection circuit, and rain detection circuit, thus powering these circuits. After the main power switch is turned on, the 220V AC power enters the power input terminal of the fan body M2 through the two control power input terminals and two normally open contacts of relay K4. Thus, depending on the installation location, the fan body M2 is powered to either introduce fresh air into the room or exhaust stale air. When it rains outdoors, the resistance between the two metal plates T decreases due to rainwater submersion (or wetting). This causes the 24V power supply to be reduced and current-limited by resistor R, resulting in a voltage difference of over 0.7V at the base of transistor Q1. Transistor Q1 conducts, and its collector outputs a low-level signal, which enters the negative power input terminal of relay K1. Relay K1 is energized, closing its control power input terminal and normally open contact, while opening its control power input terminal and normally closed contact. Consequently, the microwave detection module W3 will not be powered, and the 220V power supply will not power the fan body M2 via the two control power input terminals and two normally open contacts of relay K4. Therefore, the fan body M2 will not be powered. Simultaneously, the 24V DC power supply enters the negative and positive terminals of the electric push rod M1 via the two control power input terminals and two normally closed contacts of relay K3. At the voltage input terminal, after the electric push rod M1 is energized, its push column pushes the left outer side of the lower connecting rod 44 along the hinge point through the connecting plate 45. Under the action of the connecting rod 44, multiple baffles 41 change from a horizontal state to a vertical state. When the push column of the electric push rod M1 is at the lower stop point, multiple baffles 41 are in a vertical structure, and their rear ends are close to the inner sides of the front of the two support plates 102 (0.5 mm apart). Between each pair of baffles 41, the lower rear side of the front end of the upper support plate 41 is close to the front side of the upper end of the lower support plate 41. In this way, external rainwater can be prevented from entering the room as much as possible (at this time, even if there are people moving in the room, the microwave detection module is not energized, the relay K4 is not energized, and the corresponding fan body M2 will not be energized and work).
[0022] Figure 1 , 2As shown in Figures 3 and 4, when the outdoor rainfall stops (in actual installation, the plastic plate is tilted at about 2 degrees, with the back higher than the front, so that the water between the two metal plates T will dry out relatively quickly after the rain stops), the resistance between the two metal plates T becomes infinite because there is no rainwater to submerge (or wet) them. Therefore, no power is supplied to the base of transistor Q1, and transistor Q1 is cut off. The collector no longer outputs a low level to the negative power input terminal of relay K1. Relay K1 is de-energized and no longer engages. Its control power input terminal and normally open contact are open, while its control power input terminal and normally closed contact are closed. Thus, the microwave probe... When the test module W3 is powered on, relay K2 closes its control power input terminal and normally open contact, and opens its control power input terminal and normally closed contact. 24V DC power enters the positive and negative voltage input terminals of the electric push rod M1 through the two control power input terminals and two normally open contacts of relay K2. When the electric push rod M1 is powered on, its push column drives the left outer side of a lower connecting rod 44 to move upwards along the hinge point. When the push column of the electric push rod M1 is at its upper stop, multiple baffles 41 are in a horizontal structure (with a large distance between each pair of baffles 41), allowing outside air to enter the room or the room to be exhausted. When relay K3 is powered on, its control power input terminal and normally closed contact are open, preventing 24V power from simultaneously entering the positive and negative power input terminals of the electric push rod M1, which could cause abnormal circuit operation. After the microwave detection module W3 is powered on, if there is activity in the room, pin 3 of the module will output a high level to the positive power input terminal of relay K4. Relay K4 will then close its control power input terminal and normally open contact, energizing the fan unit M2 to either introduce fresh air into the room or expel stale air. Once the people have left the room, pin 3 of the microwave detection module W3 will stop outputting a high level, and relay K4 will de-energize, opening its control power input terminal and normally open contact, thus deactivating the fan unit M2. After the humidity detection circuit is powered on, when the indoor air humidity is relatively high, the voltage signal output from pin 3 of the humidity detection module W4 is relatively high, and vice versa. When the indoor air humidity is relatively low, the voltage signal output from pin 3 of the humidity detection module W4 is divided by the adjustable resistors RP1 and R1 and enters the base of transistor Q2, where it is below 0.7V. Transistor Q2 will not conduct, so buzzer B1 will not be powered on, indicating that the indoor air humidity is not high. When the indoor air humidity is relatively high, the voltage signal output from pin 3 of the humidity detection module W4 is divided by the adjustable resistors RP1 and R1 and enters the base of transistor Q2, where it is above 0.7V. Transistor Q2 will conduct, and its collector will output a low level, which enters the negative power input terminal of buzzer B1. Therefore, buzzer B1 will be powered on and will sound, indicating that the indoor air humidity is high.
[0023] Figure 1 , 2As shown in Figures 3 and 4, through the operation of all the circuits described above, in this new application, the fan body will only be powered on and automatically open the shielding mechanism to allow fresh air into the room when there is no rain outside and people are inside. When no one is inside or it is raining outside, the power switch of the fan body will be automatically turned off, and the shielding mechanism will be closed when it rains. This achieves automatic control and energy saving, and minimizes the problem of rainwater entering the room with the airflow. When the indoor humidity exceeds the threshold due to various reasons, the buzzer will promptly sound to actively prompt the staff to take corresponding measures (such as placing easily damp items separately in relevant boxes to prevent them from getting damp). This minimizes the adverse effects of excessive indoor humidity on related equipment or reagents. Figure 4 In the circuit, transistors Q1 and Q2 are NPN transistors of model 9013; resistor R has a resistance of 1KΩ; resistor R1 has a resistance of 10KΩ; buzzer B1 is an active continuous-sound buzzer alarm of model FM24V; power module W1 is an AC 220V to DC 24V power module; the electric actuator is a small electric telescopic actuator of model 10W (with limit switches at the upper and lower ends of the cylinder; the internal motor is de-energized when the actuator reaches its stop point, and energized by reverse input power); relays K1, K2, K3, and K4 are DC 24V; the fan body M2 has a power of 600W and a voltage of AC 220V; humidity detection module W4 is a humidity sensor of model KS-SHT14A, which has two power input terminals and one... The signal output terminal has a higher voltage signal for higher humidity levels and a lower voltage signal for lower humidity levels. The microwave detection module W3 is a finished microwave radar induction switch module with model number RCWL-0515. The microwave detection module W3 has two power input terminals, one signal output terminal, and a detection distance of 12 meters (power is output when a human signal is detected, and not output otherwise). The adjustable resistor RP1 has a resistance value of 1K (the higher the resistance value is adjusted by the technician, the more likely the buzzer B1 will be energized and sound when the indoor humidity is high, which means the humidity detection threshold is set relatively high; the lower the resistance value is adjusted by the technician, the more likely the buzzer B1 will be energized and sound when the indoor humidity is low, which means the humidity detection threshold is set relatively low).
[0024] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. It will be apparent to those skilled in the art that this utility model is limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or basic characteristics of this utility model. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of this utility model is defined by the appended claims rather than the foregoing description, and thus all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this utility model.
[0025] Furthermore, it should be understood that although this specification describes the embodiments, the embodiments do not necessarily contain only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in the embodiments can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. A ventilation device, comprising a fan body and a housing, characterized in that, It also includes a rainwater detection circuit, a control circuit, a humidity detection circuit, and a shielding plate mechanism; the rear end of the housing has a fixing plate, the fan body is fixedly installed inside the housing, the rainwater detection circuit is equipped with at least two metal plates, the two metal plates are fixedly installed on the upper end of the housing with insulation between them; the shielding plate mechanism includes an electric push rod and multiple shielding plates and connecting plates, one side of the shielding plate has a shaft, the other side of the shielding plate has a connecting rod, the front end of the housing has two support plates, the support plates have multiple shaft holes; the multiple shafts on one side of the multiple shielding plates and the multiple connecting rods on the other side of the multiple shielding plates are located inside the... The outer sides of the multiple connecting rods of the multiple baffle plates are respectively rotated and fitted into multiple shaft holes of the connecting plate. The upper end of the electric push rod is hinged and installed on the front outer side of the housing, and the lower end of the electric push rod is rotated and fitted onto the outer side of the lowest connecting rod. A baffle plate is installed on the upper part of the front side of the housing. The rainwater detection circuit, control circuit, and humidity detection circuit are installed in the component box. The power output terminal of the control circuit is electrically connected to the power input terminal of the electric push rod and the fan body, and the signal input terminal of the control circuit is electrically connected to the signal output terminal of the rainwater detection circuit.
2. The ventilation device according to claim 1, characterized in that, When the push rod of the electric actuator is at the upper stop point, the multiple baffles are in a horizontal structure. When the push rod of the electric actuator is at the lower stop point, the multiple baffles are in a vertical structure, and there is a sealed contact between every two baffles.
3. A ventilation device according to claim 1, characterized in that, The control circuit includes four electrically connected relays and a microwave detection module. The normally closed contact of the first relay is connected to the positive power input terminal of the microwave detection module and the positive power input terminal of the third relay. The normally open contact of the first relay is connected to the positive power input terminal of the second relay. The negative power input terminal and negative control power input terminal of the second relay are connected to the negative power input terminal and negative control power input terminal of the third relay, the negative power input terminal of the fourth relay, and the negative power input terminal of the microwave detection module. The power output terminal of the microwave detection module is connected to the positive power input terminal of the fourth relay. The positive power input terminal and positive control power input terminal of the first relay are connected to the positive control power input terminals of the second and third relays.
4. A ventilation device according to claim 1, characterized in that, The humidity detection circuit includes a humidity detection module, an adjustable resistor, a transistor, a resistor, and a buzzer, which are electrically connected. The positive power input terminal of the humidity detection module is connected to the positive power input terminal of the buzzer. The output terminal of the humidity detection module is connected to one end of the adjustable resistor, one end of the resistor, and the base of the transistor. The collector of the transistor is connected to the negative power input terminal of the buzzer. The emitter of the transistor is connected to the negative power input terminal of the humidity detection module.
5. A ventilation device according to claim 1, characterized in that, The rain detection circuit includes an electrically connected resistor and a transistor, and is electrically connected to two metal plates. One of the metal plates is connected to one end of the resistor, and the other end of the resistor is connected to the base of the transistor.
6. A ventilation device according to claim 1, characterized in that, The probes of the humidity detection module and the microwave detection module are located on the front of the component box.