An electronic communication cabinet based on the Internet of Things and a control method thereof

Abstract

The present invention discloses an electronic communication cabinet based on the Internet of Things, comprising a cabinet body and a cabinet door control device arranged on the inner side of the cabinet door; the cabinet door control device comprises at least two forward and reverse motors, and the surfaces of the output shafts of the forward and reverse motors are respectively wound with corresponding ropes, wherein one end of the first rope passes through the upper surface of the cabinet door, and one end of the second rope passes through the lower surface of the cabinet door; an upper vent and a lower vent are provided on the cabinet door, and the inner walls of the upper vent and the lower vent are respectively slidably connected with an upper ventilation plate and a lower ventilation plate, the upper ventilation plate is connected with the second rope, and the lower ventilation plate is connected with the first rope, so that the lifting and lowering of the upper and lower ventilation plates are controlled under the action of the corresponding forward and reverse motors. The present invention also discloses a corresponding control method. The present invention enables the interior of the cabinet to have a ventilation effect without opening the cabinet door, and can timely dissipate heat inside the cabinet, thereby reducing the probability of damage to electronic devices inside the cabinet.

Description

Technical Field

[0001] The present invention belongs to the technical field of electronic communication cabinets of the Internet of Things, and in particular relates to an electronic communication cabinet based on the Internet of Things and a control method thereof. Background Art

[0002] The Internet of Things, referred to as IoT, refers to the use of various information sensors, radio frequency identification technology, global positioning system, infrared sensors, laser scanners and other devices and technologies to collect any objects or processes that need to be monitored, connected, and interacted in real time, collect various required information such as sound, light, heat, electricity, mechanics, chemistry, biology, and location, and realize ubiquitous connection between objects and objects and between objects and people through various possible network accesses, and realize intelligent perception, identification and management of objects and processes. The Internet of Things is an information carrier based on the Internet, traditional telecommunications networks, etc. It allows all ordinary physical objects that can be independently addressed to form an interconnected network. The Internet of Things, or "Internet of Everything Connected", is an extended and expanded network based on the Internet. It combines various information sensing devices with the network to form a huge network to realize the interconnection of people, machines and objects at any time and any place.

[0003] An electronic communication cabinet is an independent or self-supporting housing for electrical or electronic equipment. The cabinet is generally equipped with doors, removable or non-removable side panels and back panels. It is generally made of cold-rolled steel plates or alloys, and can provide waterproof, dustproof, and electromagnetic interference protection for the stored equipment. An electronic communication cabinet based on the Internet of Things is used to integrate the relevant equipment required in the Internet of Things, which is convenient for unified installation and use, and also convenient for subsequent information extraction.

[0004] However, existing communication cabinets are all fixed cabinets, which will cause the temperature inside the cabinet to rise in hot weather and when the internal electrical appliances are continuously working. Over time, the electronic components inside the cabinet will be damaged, making it inconvenient for the electronic components inside the cabinet to work under special circumstances. Summary of the invention

[0005] In response to one or more of the above defects or improvement needs in the prior art, the present invention provides an electronic communication cabinet based on the Internet of Things and a control method thereof. Without opening the cabinet door, the interior of the cabinet is ventilated, the heat inside the cabinet can be dissipated in time, and the probability of damage to electronic devices inside the cabinet is reduced.

[0006] To achieve the above-mentioned object, according to one aspect of the present invention, there is provided an electronic communication cabinet based on the Internet of Things, comprising a cabinet body and a cabinet door control device arranged on the inner side of the cabinet door;

[0007] The cabinet door control device comprises at least two forward and reverse motors, and corresponding ropes are respectively wound around the output shaft surfaces of the forward and reverse motors, wherein one end of the first rope passes through the upper surface of the cabinet door, and one end of the second rope passes through the lower surface of the cabinet door;

[0008] An upper vent and a lower vent are provided on the cabinet door, and the inner walls of the upper vent and the lower vent are respectively slidably connected with an upper ventilation plate and a lower ventilation plate, the upper ventilation plate is connected to the second rope, and the lower ventilation plate is connected to the first rope, so that the lifting and lowering of the upper and lower ventilation plates are controlled under the action of the corresponding forward and reverse motors.

[0009] As a further improvement of the present invention, the lower surface of the upper ventilation plate and the upper surface of the lower ventilation plate are fixedly connected with semicircular rings, and the forward and reverse motors are fixedly connected to the corresponding semicircular rings through ropes.

[0010] As a further improvement of the present invention, a return spring is connected to the lower surface of the upper ventilation plate, and the other end of the return spring is fixedly connected to the bottom of the cabinet.

[0011] As a further improvement of the present invention, a plurality of temperature sensors and humidity sensors are provided at the bottom and the top of the cabinet, and the temperature sensors and humidity sensors are electrically connected to the microcontroller, and each microcontroller is electrically connected to the controller for controlling the rotation of the forward and reverse motors.

[0012] As a further improvement of the present invention, the forward and reverse motor is arranged in a motor box, and the side surface of the motor box is fixedly connected to the inner side of the cabinet door.

[0013] As a further improvement of the present invention, one end of the rope passes through the middle of the upper surface and the lower surface of the cabinet door respectively.

[0014] According to another aspect of the present invention, a control method for an electronic communication cabinet based on the Internet of Things is provided, comprising the following steps:

[0015] S1: When the temperature sensor and humidity sensor inside the cabinet sense that the humidity and temperature inside the cabinet reach a first preset value, the control switch turns on the blower and exhaust fan inside the cabinet to cool down and dehumidify the inside of the cabinet;

[0016] S2: When the cooling and dehumidification method in S1 is still higher than the second preset value within the set time, one of the forward and reverse motors inside the cabinet door is opened by the controller, and the ventilation plate at the lower vent is pulled up by the rope, or the ventilation plate at the upper vent is moved down;

[0017] S3: When the cooling and dehumidification method in S2 is still higher than the third preset value within the set time, the two forward and reverse motors are started at the same time, so that the two ventilation plates move up at the same time or move up at the same time, thereby opening the upper vents and the lower vents alternately.

[0018] As a further improvement of the present invention, step S2 specifically includes the following steps:

[0019] When the temperature or humidity at the bottom of the cabinet exceeds the preset value, the temperature sensor or humidity sensor transmits a signal to the microcontroller, and transmits a signal to the controller, and the controller controls the forward and reverse motors corresponding to the lower ventilation plate to rotate forward, and the rope pulls the lower ventilation plate to make it rise; if the temperature or humidity at the bottom of the cabinet returns to normal, the forward and reverse motors reverse, and the lower ventilation plate descends and returns to its original position;

[0020] When the temperature or humidity at the top of the cabinet exceeds the preset value, the temperature sensor or humidity sensor transmits a signal to the microcontroller and transmits a signal to the controller, which controls the forward and reverse motors corresponding to the upper ventilation plate to rotate forward, and the rope pulls down to lower the upper ventilation plate; if the temperature at the top of the cabinet returns to normal, the forward and reverse motors reverse, and the upper ventilation plate rises steadily and returns to its original position without pressure through the reset spring and rope.

[0021] As a further improvement of the present invention, the first preset value ≥ the second preset value ≥ the third preset value.

[0022] In general, the above technical solution conceived by the present invention has the following beneficial effects compared with the prior art:

[0023] (1) The Internet of Things-based electronic communication cabinet of the present invention is provided with a forward and reverse motor, a rope and a ventilation plate, so that the forward and reverse motor inside the motor box drives the ventilation plate on the side of the cabinet door to move vertically through the rope, so that the cabinet body has a ventilation effect without opening the cabinet door, and the cabinet body can be ventilated in time, thereby reducing the probability of damage to the electronic devices inside the cabinet body and reducing the workload of the staff under high temperature conditions.

[0024] (2) The control method of the electronic communication cabinet based on the Internet of Things of the present invention can remotely monitor the electronic communication cabinet of the Internet of Things through the indoor control panel and promptly handle special situations inside the cabinet. In the case of insufficient personnel, it can alleviate the problems inside the cabinet and prevent the problems from continuing to grow or become serious. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the three-dimensional structure of an electronic communication cabinet based on the Internet of Things according to an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of a side cross-sectional structure of an electronic communication cabinet based on the Internet of Things according to an embodiment of the present invention;

[0027] Figure 3 for Figure 2 Schematic diagram of the enlarged structure of the A area in the middle;

[0028] Figure 4 This is a schematic diagram of a top-down structure of an electronic communication cabinet based on the Internet of Things according to an embodiment of the present invention;

[0029] Figure 5 The control method flow involved in the embodiment of the present invention is Figure 1 ;

[0030] Figure 6 The control method flow involved in the embodiment of the present invention is Figure 2 ;

[0031] Figure 7 The control method flow involved in the embodiment of the present invention is Figure 3 .

[0032] In all the drawings, the same figure marks represent the same technical features, specifically: 1. Cabinet body; 2. Cabinet door control device; 201. Motor box; 202. Forward and reverse motor; 203. Rope; 204. Upper vent; 205. Lower vent; 206. Ventilation plate; 207. Semicircular ring; 208. Return spring. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0034] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0035] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0036] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0038] See also Figures 1 to 4 The electronic communication cabinet based on the Internet of Things of the present invention comprises a cabinet body 1 and a cabinet door control device 2, wherein the cabinet body 1 is used to fix the electronic communication device required for the Internet of Things, and the cabinet door control device 2 is arranged on the inner side of the cabinet door of the cabinet body 1. The cabinet door control device 2 comprises a motor box 201, a forward and reverse motor 202, a rope 203, an upper vent 204, a lower vent 205, a ventilation plate 206, a semicircular ring 207 and a reset spring 208.

[0039] Specifically, the side of the motor box 201 is fixedly connected to the inner side of the cabinet door, and the side of the motor box 201 facing the cabinet door is preferably open; a forward and reverse motor 202 is arranged in the motor box 201. In a specific embodiment of the present invention, two motor boxes 201 are arranged horizontally on the inner side of the cabinet door, and the two motor boxes 201 are both provided with a forward and reverse motor 202.

[0040] The forward and reverse motor 202 is electrically connected to the controller, and the output shaft surfaces of the forward and reverse motor 202 are respectively wound with corresponding ropes 203, one end of one rope (the first rope) passes through the upper surface of the cabinet door, and the other end of the rope (the second rope) passes through the lower surface of the cabinet door. Preferably, one end of the rope 203 passes through the middle of the upper and lower surfaces of the cabinet door. Correspondingly, the upper and lower surfaces of the two motor boxes 201 are both provided with round holes adapted to the ropes 203.

[0041] Furthermore, an upper vent 204 and a lower vent 205 are provided on the cabinet door, and a square hole is provided on the inner bottom wall of the upper vent 204, and a vent plate 206 is slidably connected to the inner walls of the upper vent 204 and the lower vent 205. The upper vent 204 is slidably connected to the upper vent plate, and the lower vent 205 is slidably connected to the lower vent plate. A semicircular ring 207 is fixedly connected to the lower surface of the upper vent plate, and a semicircular ring 207 is fixedly connected to the upper surface of the lower vent plate. The forward and reverse motors 202 are fixedly connected to the corresponding semicircular rings 207 through ropes 203 on the surface of the output shaft.

[0042] Specifically, the first rope is connected to the semicircular ring of the lower ventilation plate, and the second rope is connected to the semicircular ring of the upper ventilation plate.

[0043] In a preferred embodiment, a return spring 208 is provided on the lower surface of the upper ventilation plate, one end (top end) of the return spring 208 is fixedly connected to the upper ventilation plate, and the other end (bottom end) is fixedly connected to the bottom of the cabinet body, and one end of the rope 203 passes through the return spring 208. By providing the return spring 208 and the rope 203, the upper ventilation plate can rise slowly without tension.

[0044] The present invention arranges a motor box on the inner side of the cabinet door, and the forward and reverse motors inside the motor box drive the ventilation plate on the side of the cabinet door to move vertically through ropes, so that the interior of the cabinet can be ventilated without opening the cabinet door, thereby reducing the workload of the staff under high temperature conditions.

[0045] See also Figures 5 to 7 The control method of the electronic communication cabinet based on the Internet of Things of the present invention comprises the following steps:

[0046] S1: When the temperature sensor and humidity sensor inside the cabinet 1 sense that the humidity and temperature inside the cabinet 1 reach a first preset value, the control switch turns on the blower and exhaust fan provided inside the cabinet 1 to cool down and dehumidify the inside of the cabinet 1;

[0047] Specifically, the temperature sensor and humidity sensor sense that the humidity and temperature inside the cabinet 1 have reached the preset values, and transmit signals to the central processing unit. After analysis and integration by the central processing unit, the signals are transmitted to the control panel, and the specific parameters of the existing temperature and humidity and data of different short time periods are displayed. When the operator inputs an instruction or the requirements of the preset instruction are met, the control system inside the central processing unit is triggered, and the control switch is turned on through the controller, so that the control switch turns on the blower and induced draft fan installed inside the cabinet 1 to cool and dehumidify the interior of the cabinet 1.

[0048] S2: When the cooling and dehumidification method in S1 is still higher than the second preset value within the set time, the forward and reverse motor 202 inside one of the motor boxes 201 on the inside of the cabinet door is opened through the controller, and the ventilation plate 206 at the lower vent 205 is pulled up or the ventilation plate 206 at the upper vent 204 is moved down through the rope.

[0049] Specifically, the central processing unit outputs a signal to the controller, and opens the forward and reverse motor 202 inside one of the motor boxes 201 on the inside of the cabinet door through the controller, winds the rope 203 around the output shaft of the forward and reverse motor 202, and pulls the ventilation plate 206 at the lower vent 205 on the side of the cabinet door through the rope 203, so that the ventilation plate 206 moves up and opens the lower vent 205 on the side of the cabinet door; or, opens the forward and reverse motor 202 inside another motor box 201 on the inside of the cabinet door through the controller, winds the rope 203 around the output shaft of the forward and reverse motor 202, and pulls the ventilation plate 206 at the upper vent 204 on the side of the cabinet door through the rope 203, so that the ventilation plate 206 moves down; thereby, the gas inside the cabinet body 1 circulates, which facilitates the acceleration of cooling and dehumidification efficiency.

[0050] In a preferred embodiment, Figure 6 and 7 As shown, a number of temperature sensors and humidity sensors are provided at the bottom and top of the cabinet, which are used to sense the temperature and humidity at the top and bottom of the cabinet, respectively. When the temperature at the bottom of the cabinet exceeds the temperature limit set by the temperature sensor or the humidity exceeds the humidity limit set by the humidity sensor, the temperature sensor or humidity sensor transmits a signal to the microcontroller, and the microcontroller transmits a signal to the controller, and the controller controls the forward and reverse motor corresponding to the lower ventilation plate to rotate forward, and the forward and reverse motor pulls the lower ventilation plate through a rope to make the lower ventilation plate rise, so that the airflow inside the cabinet can communicate with the outside, and heat dissipation or dehumidification is convenient. Similarly, when the temperature or humidity at the bottom of the cabinet returns to normal, the forward and reverse motor reverses, and the lower ventilation plate descends and returns to its original position;

[0051] When the temperature at the top of the cabinet exceeds the temperature limit set by the temperature sensor or the humidity exceeds the humidity limit set by the humidity sensor, the temperature sensor or the humidity sensor transmits a signal to the microcontroller, and the microcontroller transmits a signal to the controller, and the controller controls the forward and reverse motors corresponding to the upper ventilation plate to rotate forward, and the forward and reverse motors pull the ventilation plate through the rope to lower the upper ventilation plate, so as to facilitate the circulation of air at the top of the cabinet and the outside. Similarly, when the temperature at the top of the cabinet returns to normal, the forward and reverse motors reverse, and the upper ventilation plate rises steadily and returns to its original position through the reset spring and the rope without pressure.

[0052] S3: When the cooling and dehumidification method in S2 is still higher than the third preset value within the set time, the two forward and reverse motors 202 are started at the same time, so that the two ventilation plates 206 move up at the same time or move up at the same time, thereby alternately opening the upper vents 204 and the lower vents 205.

[0053] Specifically, the central processor sends a signal to the controller, so that the controller starts the forward and reverse motors 202 inside the two motor boxes 201 inside the cabinet door. When the first forward and reverse motor 202 rotates forward, the ventilation plate 206 at the lower ventilation hole 205 on the side of the cabinet door is pulled by the rope 203 to open the lower ventilation hole 205 of the cabinet door.

[0054] When the first forward and reverse motor 202 is reversed, the second forward and reverse motor 202 is started at the same time, so that the first forward and reverse motor 202 is reversed to loosen the rope 203, so that the ventilation plate 206 at the lower ventilation hole 205 on the side of the cabinet door slowly returns to its original position, and the second forward and reverse motor 202 pulls the ventilation plate 206 at the upper ventilation hole 204 on the side of the cabinet door through the rope 203, so that both ventilation plates 206 move downward to open the upper ventilation hole 204 on the side of the cabinet door; similarly, the ventilation plates 206 can be controlled to move upward to open the lower ventilation hole 205. Thus, the upper and lower ventilation holes are opened alternately, the air outlet direction inside the cabinet body 1 is adjusted, and the high temperature and moisture inside the cabinet body 1 are prevented from being deposited inside the cabinet body 1.

[0055] It should be noted that the first preset value ≥ the second preset value ≥ the third preset value.

[0056] The control method of the electronic communication cabinet based on the Internet of Things of the present invention monitors the electronic communication cabinet of the Internet of Things remotely through an indoor control panel, and promptly handles special situations occurring inside the cabinet. In the case of insufficient personnel, it can alleviate problems occurring inside the cabinet and prevent the problems from continuing to grow or become serious.

[0057] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An electronic communication cabinet based on the Internet of Things, characterized in that: It comprises a cabinet body (1) and a cabinet door control device (2) arranged on the inner side of the cabinet door; The cabinet door control device (2) comprises at least two forward and reverse motors (202), and corresponding ropes (203) are respectively wound around the output shaft surfaces of the forward and reverse motors (202), wherein one end of the first rope passes through the upper surface of the cabinet door, and one end of the second rope passes through the lower surface of the cabinet door; An upper vent (204) and a lower vent (205) are provided on the cabinet door, and the inner walls of the upper vent (204) and the lower vent (205) are slidably connected with an upper vent plate and a lower vent plate, respectively. The upper vent plate is connected to a second rope, and the lower vent plate is connected to a first rope, so that the lifting and lowering of the upper and lower vent plates are controlled under the action of the corresponding forward and reverse motors (202); A return spring (208) is connected to the lower surface of the upper ventilation plate, and the other end of the return spring (208) is fixedly connected to the bottom of the cabinet; The cabinet (1) is provided with a plurality of temperature sensors and humidity sensors at the bottom and top, the temperature sensors and humidity sensors are electrically connected to a microcontroller, and each microcontroller is electrically connected to the controller, for controlling the rotation of the forward and reverse motors; The control method of the electronic communication cabinet based on the Internet of Things comprises the following steps: S1: When the temperature sensor and humidity sensor inside the cabinet sense that the humidity and temperature inside the cabinet reach a first preset value, the control switch turns on the blower and exhaust fan inside the cabinet to cool down and dehumidify the inside of the cabinet; S2: When the cooling and dehumidification method in S1 is still higher than the second preset value within the set time, one of the forward and reverse motors inside the cabinet door is opened by the controller, and the ventilation plate at the lower vent is pulled up by the rope, or the ventilation plate at the upper vent is moved down; S3: When the temperature of the cooling and dehumidification method in S2 is still higher than the third preset value within the set time, the two forward and reverse motors are started at the same time, so that the two ventilation plates move up or down at the same time, thereby opening the upper ventilation opening and the lower ventilation opening alternately; The first preset value ≥ the second preset value ≥ the third preset value.

2. The electronic communication cabinet based on the Internet of Things according to claim 1 is characterized in that: The lower surface of the upper ventilation plate and the upper surface of the lower ventilation plate are fixedly connected with semicircular rings (207), and the forward and reverse motors (202) are respectively fixedly connected to the corresponding semicircular rings (207) through ropes (203).

3. The electronic communication cabinet based on the Internet of Things according to claim 1 is characterized in that: The forward and reverse motor (202) is arranged in a motor box (201), and the side surface of the motor box (201) is fixedly connected to the inner side of the cabinet door.

4. The electronic communication cabinet based on the Internet of Things according to any one of claims 1 to 3, characterized in that: One end of the rope (203) passes through the middle of the upper surface and the lower surface of the cabinet door respectively.

5. A control method for an electronic communication cabinet based on the Internet of Things according to any one of claims 1 to 4, characterized in that: The steps include: S1: When the temperature sensor and humidity sensor inside the cabinet sense that the humidity and temperature inside the cabinet reach a first preset value, the control switch turns on the blower and exhaust fan inside the cabinet to cool down and dehumidify the inside of the cabinet; S2: When the cooling and dehumidification method in S1 is still higher than the second preset value within the set time, one of the forward and reverse motors inside the cabinet door is opened by the controller, and the ventilation plate at the lower vent is pulled up by the rope, or the ventilation plate at the upper vent is moved down; S3: When the cooling and dehumidification method in S2 is still higher than the third preset value within the set time, the two forward and reverse motors are started at the same time, so that the two ventilation plates move up or down at the same time, thereby opening the upper vents and the lower vents alternately.

6. The control method according to claim 5, characterized in that: Step S2 specifically includes the following steps: When the temperature or humidity at the bottom of the cabinet exceeds the preset value, the temperature sensor or humidity sensor transmits a signal to the microcontroller, and transmits a signal to the controller, and the controller controls the forward and reverse motors corresponding to the lower ventilation plate to rotate forward, and the rope pulls the lower ventilation plate to make it rise; if the temperature or humidity at the bottom of the cabinet returns to normal, the forward and reverse motors reverse, and the lower ventilation plate descends and returns to its original position; When the temperature or humidity at the top of the cabinet exceeds the preset value, the temperature sensor or humidity sensor transmits a signal to the microcontroller and transmits a signal to the controller, which controls the forward and reverse motors corresponding to the upper ventilation plate to rotate forward, and the rope pulls down to lower the upper ventilation plate; if the temperature at the top of the cabinet returns to normal, the forward and reverse motors reverse, and the upper ventilation plate rises steadily and returns to its original position without pressure through the reset spring and rope.

7. The control method according to claim 5 or 6, characterized in that: The first preset value ≥ the second preset value ≥ the third preset value.

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