Gas detection device with ventilation function

Abstract

This invention provides a gas detection device with ventilation function, including a detection unit installed on the air intake duct of a ventilation fan. Part of the airflow inside the intake duct is guided to the detection unit by a flow guide component for gas detection, thereby utilizing the airflow within the ventilation structure to achieve real-time monitoring of the gas concentration in the kitchen. The air intake end of the flow guide component is equipped with a diversion component, which automatically adjusts the airflow entering the flow guide component according to the airflow velocity inside the intake duct to improve detection stability and response speed. When the detection unit detects a gas leak, it controls the ventilation fan to increase its speed to accelerate air circulation and gas dissipation within the kitchen. Simultaneously, the diversion component gradually moves towards a closed state under the action of high-speed airflow to reduce the obstruction of the high-speed exhaust process by the flow guide component and reduce detection fluctuations caused by the high-speed airflow to the detection unit.

Description

Technical Field

[0001] This invention relates to the field of ventilation safety, specifically to a gas detection device with ventilation function. Background Technology

[0002] Natural gas, as one of the most commonly used energy sources in kitchens, is widely used in stoves, cooking equipment, and heating equipment in residential kitchens as well as commercial kitchens such as restaurants and hotels. Because natural gas and other gaseous substances are prone to diffusion and accumulation after leakage, and are highly flammable and explosive, gas detection devices are typically installed in kitchens to monitor the concentration of gas in the kitchen air in real time. When abnormal gas concentration is detected, an alarm is triggered promptly, thereby reducing the safety risks associated with gas leaks.

[0003] Existing gas detection devices are typically stand-alone gas alarms, mostly installed on the kitchen ceiling, walls, or near gas appliances. They detect leaks by measuring the concentration of gas in the air in a localized area. For typical household kitchens, due to the relatively small space and limited airflow, gas leaks can easily spread to the detection area, thus meeting basic detection needs to a certain extent.

[0004] However, commercial kitchens, such as those in restaurants and hotels, typically have large interior spaces and often contain multiple stoves, exhaust systems, and continuously operating ventilation systems. Furthermore, the airflow within commercial kitchens is complex. With continuous ventilation, strong airflow paths are created, making it easy for the direction and accumulation area of ​​a gas leak to change due to the airflow. This makes it difficult for traditional fixed gas detection devices to remain within the main gas diffusion area.

[0005] In addition, existing gas detection devices are usually set up independently of the kitchen ventilation structure. Their detection position is fixed and the detection area is relatively limited. Especially in commercial kitchens where the space is large and the air exchange speed is fast, gas in some areas may have already flowed rapidly with the airflow inside the kitchen before it has spread to the detection device. This can easily lead to problems such as detection lag, insufficient detection stability, or missed detection in some areas.

[0006] Furthermore, most existing gas detection devices only have alarm functions. After detecting a gas leak, they can usually only alert staff through sound and light alarms, but they are difficult to effectively link with the ventilation structure inside the kitchen. They cannot actively improve the air circulation and exhaust efficiency inside the kitchen after a gas leak, thus making it difficult to quickly reduce the gas concentration inside the kitchen, resulting in the risk of gas accumulation inside commercial kitchens.

[0007] Therefore, a gas detection device with ventilation function is provided to address the above-mentioned problems. Summary of the Invention

[0008] This invention addresses the problems of existing gas detection devices in commercial kitchens, such as detection lag, insufficient detection stability, and missed detections in localized areas due to fixed detection locations and difficulty in adapting to complex airflow environments. It also addresses the problem that existing gas detection devices are difficult to effectively integrate with kitchen ventilation structures and cannot quickly reduce the gas concentration inside the kitchen. Therefore, this invention provides a gas detection device with ventilation functions.

[0009] The present invention solves the above-mentioned technical problems through the following technical solutions: This invention provides a gas detection device with ventilation function, including a detection unit with gas detection function. The detection unit is installed on the air intake pipe of the ventilation fan. A portion of the airflow flowing into the air intake pipe is guided to the detection end of the detection unit through a flow guiding component, so that the detection unit can detect the gas entering the air intake pipe in real time, thereby improving the timeliness of gas leak detection. The flow guide component is located on one side of the inner cavity of the air intake pipe, and the air intake end of the flow guide component is provided with a flow diversion component. The flow diversion component changes the introduced air flow rate according to the airflow velocity inside the air intake pipe. The higher the flow velocity, the more air flow enters the flow guide component. After detecting a gas leak, the detection unit controls the ventilation fan to increase its speed to accelerate the air circulation and exhaust speed inside the kitchen, thereby reducing the gas concentration inside the kitchen; and as the flow velocity inside the air intake pipe further increases, the diversion component moves toward a closed state under the action of airflow.

[0010] In this technical solution, the flow guiding component includes a ring-shaped manifold shell, which is fitted around the air intake pipe. Multiple air intake shells arranged in a ring array are connected to one side of the outer wall of the manifold shell. The ends of the air intake shells penetrate the side wall of the air intake pipe and extend away from the ventilation fan. A guide shell is connected to the outer wall of the other side of the manifold housing, and the guide shell wraps around the detection end of the detection unit; A flow-guiding assembly is connected to one end of the inlet shell.

[0011] The inner cavities of the inlet shell, the manifold shell, and the guide shell are interconnected to form a flow channel for airflow. A connecting pipe is provided on the guide shell, which is connected to the inner cavity of the intake pipe, thereby forming a circulating connection structure between the flow channel and the intake pipe.

[0012] In this technical solution, the flow-guiding component is a first flow-guiding component. The first flow-guiding component includes a connecting shell. One end of the connecting shell is connected to the outer wall of the inlet shell, and the other end of the connecting shell is a circular air inlet port. A first flow-guiding part is provided on the air inlet port. The cross-sectional area of ​​the first flow-guiding part gradually increases from one side to the other side to form a frustum-shaped shell structure. The side with the smaller cross-sectional area of ​​the first flow-guiding part is connected to the air inlet port, and the other side is set towards the side away from the ventilation fan and the inlet shell. An air inlet is formed on the side with a larger cross-sectional area of ​​the first guide section. The air inlet can gradually increase in size as the gas flow rate in the air intake pipe increases, so as to increase the air flow rate entering the guide component. After the gas flow rate in the air intake pipe further increases, the first guide section drives the air intake port to move towards the closed state until it is closed, so as to reduce the airflow entering the guide component.

[0013] In this technical solution, the first flow guide includes a bearing shaft, and a frustum-shaped flow guide shell is fitted around the bearing shaft. The bearing shaft is set on the central shaft of the air intake port and is fixed to the inner wall of the air intake port by a rod. A guide block is slidably sleeved on the surface of the bearing shaft. The guide block and the flow guide shell are connected by a drive. The air intake opening on the side with the larger cross-sectional area of ​​the flow guide shell increases or decreases, causing the guide block to slide on the bearing shaft, thereby causing the sealing plate to move. The sealing plate can overlap the air intake port. A first spring is sleeved on the surface of the bearing shaft, and the two ends of the first spring are fixed to the bearing shaft and the guide block, respectively.

[0014] In this technical solution, the air guide shell includes multiple support rods rotatably connected to the air intake port, and two adjacent support rods are connected by a fan-shaped air guide cover; One end of the support rod is rotatably connected to the transmission rod, and the other end of the transmission rod is rotatably connected to the guide block. A sealing plate is fixedly connected to the side of the guide block near the air intake port by a rod, and the sealing plate is slidably sleeved on the bearing shaft.

[0015] In this technical solution, the flow-guiding component is a second flow-guiding component. The second flow-guiding component includes an air inlet opening that is rotatably connected to a guide plate on the flow-guiding component. The air inlet opening is located on the end of the inlet shell and is close to the center of the inlet pipe. The air inlet opening is opened on the inlet shell and is arranged along the axial direction of the inlet pipe, facing the side where the airflow enters. A first coil spring is provided at the rotatable connection between the guide plate and the inlet shell. The two ends of the first coil spring are respectively fixed on the guide plate and the inlet shell. A cover plate that can cover the air intake opening is rotatably connected to the top of the air intake opening. A second coil spring is provided at the rotatable connection between the cover plate and the air intake shell. The two ends of the second coil spring are fixed to the cover plate and the air intake shell respectively. The cover plate is supported by the elastic force of the second coil spring and is set along the axial direction of the air intake pipe. That is, when the second coil spring does not deform, the cover plate is set along the axial direction of the air intake pipe. The cover plate and the guide plate are connected by transmission. It also includes a drive unit that is connected to the guide vane. The drive unit is driven by the airflow that reaches a preset flow rate, causing the guide vane to rotate toward the center of the air intake pipe.

[0016] In this technical solution, the drive unit includes a drive component and a transmission component that can scoop up the airflow. The drive component is connected to the guide plate through the transmission component. After the drive component is pushed by the airflow with sufficient velocity, it drives the guide plate to rotate towards one side of the central area of ​​the air intake pipe through the transmission component, thereby increasing the tilt angle of the guide plate. This facilitates the introduction of sufficient gas to be detected into the guide assembly when the airflow velocity increases.

[0017] In this technical solution, the drive unit is closer to the ventilation fan than the guide plate. The transmission component includes a connecting crossbar. One end of the connecting crossbar is rotatably connected to the guide plate, and the other end is fixed to the slider. The slider is slidably connected to the guide rail arranged radially along the air intake pipe. Guide sleeves are fixed on both sides of the guide rail. The guide sleeves are slidably sleeved on the surface of the guide crossbar arranged axially along the air intake pipe. The guide crossbar is fixed to the outer wall of the air intake shell. The drive unit includes a fixed rod and a drive cover. One end of the fixed rod is fixed to the guide rail, and the other end of the fixed rod is fixed to the bowl-shaped drive cover.

[0018] In this technical solution, both sides of the guide plate and the cover plate are connected to each other by a transmission belt, and the transmission belt passes over at least one guide wheel fixed on the outer wall of the inlet shell.

[0019] Based on common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of the present invention.

[0020] The positive and progressive effects of this invention are as follows: By placing the detection unit on the ventilation structure, the detection unit can directly use the airflow in the ventilation system's intake duct as a sampling gas source, thereby achieving real-time monitoring of the gas concentration in the kitchen air and improving the continuity and environmental adaptability of the detection.

[0021] The flow guide component can automatically adjust the airflow rate entering the flow guide component according to the airflow velocity inside the air intake pipe. When the airflow velocity inside the air intake pipe is low, the flow guide component introduces only a small amount of airflow into the flow guide component to meet the basic gas sampling requirements of the detection unit. As the airflow velocity inside the air intake pipe gradually increases, the flow guide component increases the effective opening of the flow guide channel under the action of the fluid, so that the airflow rate entering the flow guide component increases synchronously. Thus, it can provide the detection unit with sufficient and stable gas samples under different operating conditions, improving the detection response speed and detection reliability.

[0022] When the detection unit detects a gas leak, it controls the ventilation fan to increase its speed, thereby enhancing the exhaust capacity of the ventilation structure and accelerating the circulation and exhaust of air inside the kitchen. This promotes the rapid dilution and dispersion of the leaked gas, reduces the gas concentration and accumulation risk inside the kitchen, especially in restaurant kitchens, and improves overall safety.

[0023] Meanwhile, as the speed of the ventilation fan increases, the airflow velocity inside the intake duct further increases. Under the action of enhanced airflow, the guide component gradually moves towards a closed state, thereby reducing or blocking the airflow from continuing to enter the guide component. This allows most of the airflow to be used for ventilation and exhaust, avoiding additional resistance from the guide component to the high-velocity exhaust process and reducing the detection fluctuations caused by the continuous impact of high-speed airflow on the detection unit, thus improving the system's operational stability and ventilation efficiency. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 For the present invention Figure 1 A structural diagram from another perspective; Figure 3 For the present invention Figure 1 A top-view structural diagram; Figure 4 For the present invention Figure 3 Schematic diagram of the cross-sectional structure at point AA; Figure 5 For the present invention Figure 4 A magnified schematic diagram of the structure at point I; Figure 6 This is a schematic diagram of the flow guiding component of the present invention; Figure 7 For the present invention Figure 6 A structural diagram from another perspective; Figure 8 For the present invention Figure 6 A schematic diagram of the cross-sectional structure; Figure 9 This is a schematic diagram of the structure of the first flow guiding component of the present invention; Figure 10 This is a schematic diagram of the internal structure of the first flow guiding component of the present invention; Figure 11 This is a schematic diagram of the overall structure of the present invention with a second flow guiding component; Figure 12 For the present invention Figure 11 A schematic diagram of the cross-sectional structure; Figure 13 This is a schematic diagram of the structure of the second flow guiding component of the present invention; Figure 14 For the present invention Figure 13A schematic diagram of the structure viewed from below; Figure 15 For the present invention Figure 13 A schematic diagram of the cross-sectional structure; Figure 16 For the present invention Figure 10 A magnified schematic diagram of the structure at point J; Figure 17 For the present invention Figure 13 A magnified schematic diagram of the structure at point K.

[0025] Explanation of reference numerals in the attached figures 1. Ventilation fan; 2. Air intake pipe; 3. Air outlet pipe; 4. Detection unit; 5. Manifold housing; 51. Guide housing; 52. Inlet housing; 6. First drainage assembly; 61. Connecting shell; 62. Bearing shaft; 63. Guide block; 64. Transmission rod; 65. Support rod; 66. Flow guide cover; 67. First sealing plate; 671. Flow groove; 68. Second sealing plate; 681. Skirt plate; 69. First spring; 7. Second drainage assembly; 71. Cover plate; 72. Guide plate; 73. Connecting crossbar; 74. Slider; 75. Guide rail; 76. Guide sleeve; 77. Guide crossbar; 78. Drive cover; 781. Fixing rod; 79. Guide wheel; 791. Transmission belt. Detailed Implementation

[0026] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments.

[0027] like Figure 1-4 As shown, a gas detection device with ventilation function includes a detection unit 4 with gas detection function. The detection unit 4 is installed on the air inlet pipe 2 of the ventilation fan 1. The gas inside the kitchen enters the ventilation fan 1 through the air inlet pipe 2 and flows out through the air outlet pipe 3 of the ventilation fan 1. Part of the airflow flowing into the air inlet pipe 2 is guided to the detection end of the detection unit 4 through the flow guide component, so that the detection unit 4 can detect the gas entering the air inlet pipe 2 in real time, thereby improving the timeliness of gas leak detection. The flow guiding component is located on one side of the inner cavity of the air inlet pipe 2, and the air inlet end of the flow guiding component is provided with a flow diversion component. The flow diversion component changes the introduced airflow according to the airflow velocity inside the air inlet pipe 2. The higher the flow velocity, the more airflow enters the flow guiding component, so that under the normal operation of the ventilation fan 1, some airflow can stably enter the detection unit 4 for detection, thereby improving the stability of the detection results and the detection sensitivity. Furthermore, as the airflow velocity inside the air inlet pipe 2 increases, the airflow entering the flow guiding component increases synchronously to improve the gas sampling efficiency. After detecting a gas leak, the detection unit 4 controls the ventilation fan 1 to increase its speed to accelerate the air circulation and exhaust speed inside the kitchen, thereby reducing the gas concentration inside the kitchen. As the flow velocity inside the air intake duct 2 further increases, the guide component moves towards a closed state under the action of the airflow to reduce or block the airflow from continuing to enter the guide component, avoiding excessive airflow entering the area of ​​the detection unit 4 and affecting the overall ventilation efficiency of the air intake duct 2, while reducing the continuous impact of high-speed airflow on the detection unit 4.

[0028] After detecting a gas leak, detection unit 4 transmits the detection signal to the controller. Upon receiving the abnormal signal, the controller activates alarm mechanisms such as the buzzer and flashing lights to warn kitchen staff through sound and light. Simultaneously, the controller increases the operating speed of ventilation fan 1 to accelerate air circulation and exhaust within the kitchen, thereby promoting the rapid dilution and dissipation of the leaked gas.

[0029] Upon receiving the alarm, relevant personnel can shut off the main gas supply pipe to the kitchen via a valve to cut off the continuous gas supply and prevent further gas leakage. After the gas supply is cut off, ventilation fan 1 will continue to run at high speed for at least 20 minutes to continuously force ventilation and gas dissipation inside the kitchen, thereby further reducing the gas concentration and the risk of gas accumulation inside the kitchen.

[0030] During the period when the ventilation fan 1 is running at high speed, as the airflow velocity inside the intake duct 2 increases, the guide component gradually moves toward a closed state under the action of high-speed airflow to reduce the airflow entering the guide component, so that most of the airflow is used for overall exhaust, thereby avoiding the guide component from generating greater resistance to the high-speed exhaust process and reducing the detection fluctuations caused by the continuous impact of high-speed airflow on the detection unit 4.

[0031] After the high-speed exhaust has been running for a preset time, the controller reduces the speed of the ventilation fan 1 to normal ventilation. At this time, the airflow diversion component gradually unblocks, allowing some of the airflow inside the intake pipe 2 to re-enter the detection unit 4 for gas detection. If the detection unit 4 continues to detect normal results, the staff will begin to investigate and repair any gas leaks in the kitchen.

[0032] The detection unit 4 in this application uses a gas detection instrument that has been disclosed and maturely applied in the prior art. Its specific structure, working principle and internal circuit control method are all conventional technical means known to those skilled in the art, and its hardware composition and basic detection mechanism will not be described in detail here.

[0033] The improvement of the detection unit 4 in this application mainly lies in its cooperation with the ventilation structure and the flow guiding components. By setting the detection unit 4 in the airflow path of the ventilation system, it can achieve continuous and stable gas sampling under the action of ventilation airflow, thereby improving the real-time performance and environmental adaptability of gas detection, and enhancing the linkage control effect of the overall system.

[0034] In this application, after detecting a gas leak, the detection unit 4 controls the ventilation fan 1 to increase its operating speed through the control system. This is a conventional linkage control scheme that has been disclosed and widely used in the prior art. Its specific control logic, signal transmission method, and fan speed regulation method are all technical means well known to those skilled in the art, and its specific control process will not be described in detail here.

[0035] For example, after the detection unit 4 detects that the gas concentration inside the kitchen has reached a preset threshold, it can send a control signal to the ventilation fan 1 through the controller to drive the ventilation fan 1 to increase its operating speed, thereby enhancing the air circulation and exhaust capacity inside the kitchen, accelerating the dissipation and dilution of leaked gas, and reducing the risk of gas accumulation inside the kitchen. The above-mentioned method of controlling the operation of ventilation equipment based on gas detection results is a relatively mature safety linkage control technology in this field.

[0036] Example 1 In this embodiment, as Figure 6 and 7 As shown, the flow guiding assembly includes a ring-shaped manifold 5, which is fitted around the air intake pipe 2. Multiple air intake shells 52 arranged in a ring array are connected to one side of the outer wall of the manifold 5. The ends of the air intake shells 52 penetrate the side wall of the air intake pipe 2 and extend away from the ventilation fan 1. A guide shell 51 is connected to the outer wall of the other side of the manifold 5, and the guide shell 51 wraps around the detection end of the detection unit 4. A flow guide assembly is connected to one end of the inlet shell 52.

[0037] When the ventilation fan 1 is running, a flowing airflow is formed inside the intake duct 2. After passing through the fan, the airflow flows out through the outlet duct 3. Some of the airflow in the intake duct 2 is guided into the intake shell 52 by the guide component when it passes through the guide component. Since the intake shell 52 is connected to the confluence shell 5, the airflow entering the intake shell 52 further flows into the inner cavity of the confluence shell 5, where it converges and is buffered. This helps to reduce airflow fluctuations and improve the stability of the airflow entering the detection area.

[0038] Furthermore, a miniature vortex fan can be added to the detection unit 4. The miniature vortex fan is used to assist in the suction of airflow inside the guide channel, which helps to increase the speed of airflow through the detection end and improve the airflow renewal efficiency in the detection area, thereby further improving the real-time performance and sensitivity of gas detection.

[0039] Subsequently, the converged airflow continues to flow into the guide shell 51, and under the guidance of the guide shell 51, it flows through the detection end of the detection unit 4, enabling the detection unit 4 to detect the gas concentration of the introduced airflow, thereby realizing real-time monitoring of the gas state inside the intake pipe 2.

[0040] After the test is completed, the airflow eventually flows back to the inner cavity of the air intake pipe 2 through the connecting pipe, so that a circulating airflow path is formed inside the flow guide component. This avoids the airflow from stagnating in the test area for a long time and is conducive to continuously introducing new airflow for testing, thereby improving the real-time performance and accuracy of the test.

[0041] Meanwhile, the sequential flow guidance, convergence and orientation structure between the inlet shell 52, the confluence shell 5 and the guide shell 51 makes the airflow entering the detection unit 4 more stable and uniform, thereby reducing the detection fluctuation problem caused by the high-speed airflow inside the inlet pipe 2 directly impacting the detection end, and helping to improve the stability and reliability of the detection results.

[0042] Example 2 like Figure 8-10 As shown, the flow diversion component is the first flow diversion component 6. The first flow diversion component 6 includes a connecting shell 61. One end of the connecting shell 61 is connected to the outer wall of the inlet shell 52, and the other end of the connecting shell 61 is a circular air inlet port. A first flow diversion part is provided on the air inlet port. The cross-sectional area of ​​the first flow diversion part gradually increases from one side to the other side to form a frustum-shaped shell structure. The side with the smaller cross-sectional area of ​​the first flow diversion part is connected to the air inlet port, and the other side is set towards the side away from the ventilation fan 1 and the inlet shell 52. An air inlet is formed on the side with a larger cross-sectional area of ​​the first guide section. The air inlet can gradually increase in size as the gas flow rate in the air intake pipe 2 increases, so as to increase the air flow rate entering the guide component. After the gas flow rate in the air intake pipe 2 further increases, the first guide section drives the air intake port to move towards the closed state until it is closed, so as to reduce the airflow entering the guide component.

[0043] Specifically, the first intake section includes a bearing shaft 62, and a frustum-shaped guide shell is fitted around the bearing shaft 62. The bearing shaft 62 is set on the central shaft of the air intake port, and the bearing shaft 62 is fixed to the inner wall of the air intake port by a rod. A guide block 63 is slidably sleeved on the surface of the bearing shaft 62. The guide block 63 is connected to the guide shell in a transmission manner. When the air intake opening on the side with the larger cross-sectional area of ​​the guide shell increases or decreases, it causes the guide block 63 to slide on the bearing shaft 62, thereby causing the sealing plate to move. The sealing plate can overlap the air intake port. Furthermore, such as Figure 9 As shown, a first spring 69 is sleeved on the surface of the bearing shaft 62, and the two ends of the first spring 69 are fixed on the bearing shaft 62 and the guide block 63, respectively.

[0044] Furthermore, the air guide shell includes multiple support rods 65 rotatably connected to the air intake port, and adjacent support rods 65 are connected by a fan-shaped air guide cover 66. The surface of the support rod 65 is rotatably connected to one end of the transmission rod 64, and the other end of the transmission rod 64 is rotatably connected to the guide block 63.

[0045] Preferred, such as Figure 10 As shown, the sealing plate is divided into a first sealing plate 67 and a second sealing plate 68. The first sealing plate 67 has a flow groove 671 with the same geometric dimensions as the second sealing plate 68, and the first sealing plate 67 and the second sealing plate 68 are fitted together to form a complete circular structure.

[0046] In the first sealing plate 67 and the second sealing plate 68, one of them is slidably sleeved on the bearing shaft 62, and the other is fixed on the inner wall of the air inlet port. The outer periphery of the second sealing plate 68 protrudes outward to form a skirt plate 681. Through the overlap of the skirt plate 681 with the side wall of the flow channel 671, the first sealing plate 67 and the second sealing plate 68 can overlap each other to form a complete circular structure.

[0047] The guide block 63, near the air intake port, is fixedly connected to either the first sealing plate 67 or the second sealing plate 68, which is slidably sleeved on the bearing shaft 62, via a rod. The sealing plate consists of two parts, which can prevent the sealing plate from excessively obstructing the airflow into the guide assembly during the detection state.

[0048] Specifically, such as Figure 16As shown, the first sealing plate 67 or the second sealing plate 68, which is fixed to the air intake port, is fixed at the air intake port by a rod.

[0049] When the first sealing plate 67 or the second sealing plate 68 overlaps to form a complete sealing plate, the first sealing plate 67 or the second sealing plate 68, which is fixedly connected to the air intake port, is used as a reference to cover or overlap the air intake port.

[0050] When the first spring 69 does not deform, the first spring 69 limits the position of the guide block 63 on the bearing shaft 62, thereby causing all the support rods 65 to be tilted and together form a frustum-shaped skeleton, which together with the flow guide soft cover 66 between two adjacent support rods 65 forms a frustum-shaped flow guide shell.

[0051] When the airflow velocity inside the intake pipe 2 is normal, the first spring 69 does not deform. Its elasticity, which maintains its length, allows the guide shell to maintain its frustum-shaped structure.

[0052] When the airflow velocity inside the intake pipe 2 increases, the airflow enters the guide shell and "expands" the guide shell, causing the support rod 65 to rotate away from the bearing shaft 62. The guide block 63 moves towards the side closer to the intake port, thereby driving the first sealing plate 67 or the second sealing plate 68 to move towards the intake port until the first sealing plate 67 and the second sealing plate 68 overlap each other to form a complete sealing plate.

[0053] When the detection unit 4 detects gas, it transmits a signal to the central control of the ventilation system, thereby increasing the speed of the ventilation fan 1 and greatly increasing the airflow velocity inside the intake pipe 2. This drives the sealing plate to move towards the intake port until it overlaps or covers the intake port, reducing or blocking the airflow from entering the guide assembly.

[0054] When the opening size on the air inlet side of the guide shell increases or decreases, the guide soft cover 66 can deform accordingly to adapt to the change in the size of the air inlet end of the guide shell, thereby ensuring the continuity and sealing of the guide channel.

[0055] Specifically, the flow guide cover 66 has elasticity and extensibility. When the air inlet opening of the flow guide shell expands, the flow guide cover 66 can expand synchronously through the stretching deformation of its own material to increase the flow guide space. When the air inlet opening of the flow guide shell shrinks, the flow guide cover 66 can shrink synchronously by relying on its own elasticity, thereby reducing the internal space of the flow guide channel and avoiding the problems of wrinkle accumulation or airflow turbulence in the flow guide cover 66.

[0056] Furthermore, a reserved groove may be provided on the flow guide cover 66, which can serve as a deformation buffer area for the flow guide cover 66. During the process of changing the size of the air inlet opening of the flow guide cover, the reserved groove can expand or fold to cooperate with the flow guide cover 66 to expand and contract, thereby reducing the tensile stress in local areas of the flow guide cover 66 and improving the stability and service life of the flow guide cover 66 during repeated deformation.

[0057] Meanwhile, the flexible telescopic structure of the flow guide cover 66, in conjunction with the reserved slot, enables the flow guide cover 66 to maintain a flexible fit to the flow guide channel under different airflow conditions. This helps to maintain the stability of airflow delivery, reduce airflow leakage and turbulence, and improve the guiding effect of the flow guide component on airflow.

[0058] In the above technical solution, the movement of the first drainage component 6 essentially belongs to: "The dynamic balance process between air flow pressure and the elastic restoring force of the first spring 69".

[0059] Therefore, the following parameter relationship can be established between the gas flow velocity inside the intake pipe 2, the elastic force of the first spring 69, and the force on the sealing plate.

[0060] First, as the airflow velocity inside intake duct 2 increases, the airflow entering the guide shell generates aerodynamic force on the guide shell. This aerodynamic force can be approximated as the force generated by the airflow pressure, and its magnitude is proportional to the square of the airflow velocity. F_air = 1 / 2ρv²SC in: F_air represents the force exerted by the airflow on the guide shell; ρ is the gas density; v is the airflow velocity inside intake pipe 2; S is the windward area of ​​the guide shell; C is the aerodynamic coefficient.

[0061] Therefore, we can conclude that: When the airflow velocity inside the intake pipe 2 increases, the driving force generated by the airflow on the guide shell and support rod 65 increases rapidly.

[0062] After the guide shell undergoes "expansion" deformation under the action of airflow, it pushes the guide block 63 to move along the bearing shaft 62 through the transmission rod 64, and compresses the first spring 69.

[0063] The elastic restoring force generated by the first spring 69 satisfies: F_spring = kx in: F_spring represents the spring force of the first spring, which is 69. k is the spring constant of the first spring 69; x represents the compression of the first spring 69.

[0064] therefore: As the guide block 63 moves a greater distance, the restoring force of the first spring 69 increases accordingly.

[0065] Under stable structural conditions, whether the guide shell continues to deploy and the sealing plate continues to move depends on the balance between the aerodynamic force and the spring restoring force, i.e.: F_air ≥ F_spring + F_f in: F_f represents the frictional resistance during the movement of the guide block 63, transmission rod 64, and sealing plate.

[0066] Right now: When the aerodynamic force is less than the restoring force of the first spring 69, the guide shell maintains its original frustum-shaped structure. When the aerodynamic force gradually increases and exceeds the restoring force of the first spring 69, the guide block 63 begins to move; As the aerodynamic force increases further, the sealing plate gradually moves towards the air inlet port; When the aerodynamic force reaches the preset value, the first sealing plate 67 and the second sealing plate 68 overlap each other until a complete seal is formed.

[0067] Furthermore, the driving force on the sealing plate mainly comes from: The power transmission force generated by the deployment of the flow guide shell; The airflow directly acts on the pressure of the sealing plate surface.

[0068] The force on the sealing plate can be approximated as: F_plate = P·A in: F_plate represents the force applied to the sealing plate; P is the airflow pressure; A represents the pressure-bearing area of ​​the sealing plate.

[0069] because: P ∝ v² therefore: The higher the airflow velocity inside the intake pipe 2, the greater the pushing force on the sealing plate.

[0070] In summary, the above structures form the following interconnected relationships: As the airflow velocity increases, the aerodynamic force inside the guide shell increases, the support rod 65 expands outward, the guide block 63 compresses or stretches the first spring 69, and the sealing plate gradually moves towards the air inlet port, eventually sealing the air inlet port.

[0071] Through the above parameter relationships, the first flow guiding component 6 can automatically adjust the flow guiding state according to the airflow velocity inside the air intake pipe 2, thereby taking into account both the stable sampling requirements under normal detection conditions and the low-resistance ventilation requirements under high flow velocity exhaust conditions.

[0072] Example 3 like Figure 11-15 As shown, the flow diversion component is the second flow diversion component 7. The second flow diversion component 7 includes a guide plate 72 rotatably connected to the air inlet opening on the inlet shell 52, and located near the center of the air inlet pipe 2. The air inlet opening is opened on the inlet shell 52 and is arranged along the axial direction of the air inlet pipe 2, facing the side where the airflow enters. A first coil spring is provided at the rotatable connection between the guide plate 72 and the inlet shell 52. The two ends of the first coil spring are respectively fixed to the guide plate 72 and the inlet shell 52. A cover plate 71 that can cover the air intake opening is rotatably connected to the top of the air intake opening. A second coil spring is provided at the rotatable connection between the cover plate 71 and the inlet shell 52. The two ends of the second coil spring are fixed to the cover plate 71 and the inlet shell 52 respectively. The cover plate 71 is supported by the elastic force of the second coil spring and is set along the axial direction of the air intake pipe 2. That is, when the second coil spring does not deform, the cover plate 71 is set along the axial direction of the air intake pipe 2. The cover plate 71 and the guide plate 72 are connected by transmission. It also includes a drive unit that is connected to the guide plate 72. The drive unit is driven by the airflow that reaches a preset flow rate, causing the guide plate 72 to rotate toward the center of the air intake pipe 2.

[0073] Preferably, when the first coil spring does not deform, the guide plate 72 is tilted towards the center of the air intake pipe 2 at an angle of less than 5°.

[0074] The drive unit includes a drive component and a transmission component that can scoop up the airflow. The drive component is connected to the guide plate 72 via the transmission component. After being pushed by the airflow with sufficient velocity, the drive component drives the guide plate 72 to rotate toward one side of the central region of the air intake pipe 2 via the transmission component, thereby increasing the tilt angle of the guide plate 72. This facilitates the introduction of a sufficient amount of gas to be detected into the guide assembly when the airflow velocity increases.

[0075] The drive unit is closer to the ventilation fan 1 than the guide plate 72. The transmission component includes a connecting crossbar 73. One end of the connecting crossbar 73 is rotatably connected to the guide plate 72, and the other end is fixed to the slider 74. The slider 74 is slidably connected to the guide rail 75 arranged radially along the air intake pipe 2. Guide sleeves 76 are fixed on both sides of the guide rail 75. The guide sleeves 76 are slidably sleeved on the surface of the guide crossbar 77 arranged axially along the air intake pipe 2. The guide crossbar 77 is fixed to the outer wall of the inlet shell 52. Preferred, such as Figure 14 As shown, both ends of the guide crossbar 77 are fixed to the outer wall of the inlet shell 52.

[0076] The drive unit includes a fixing rod 781 and a drive cover 78. One end of the fixing rod 781 is fixed to the guide rail 75, and the other end of the fixing rod 781 is fixed to the bowl-shaped drive cover 78.

[0077] The airflow blows onto the surface of the bowl-shaped drive cover 78 that can catch the airflow. When the flow velocity reaches a predetermined value and generates sufficient thrust, it drives the guide plate 72 to rotate.

[0078] When the airflow reaches the preset value, the thrust generated by the drive cover 78 causes the drive cover 78 to move in the same direction as the airflow, thereby driving the guide rail 75 to move. The guide rail 75 drives the guide plate 72 to rotate through the slider 74 and the connecting crossbar 73. During this process, the slider 74 slides on the guide rail 75, and the guide rail 75 slides on the guide crossbar 77 through the guide sleeve 76.

[0079] During the above process, the inner cavity of the drive cover 78 is always aligned with the direction of airflow.

[0080] like Figure 13 and 17 As shown, both sides of the guide plate 72 and the cover plate 71 are connected to each other by a transmission belt 791, and the transmission belt passes over at least two guide wheels 79. One guide wheel 79 is fixed on the bottom outer wall of the inlet shell 52, that is, it is set at the rotatable connection between the guide plate 72 and the inlet shell 52. The other guide wheel 79 is fixed on the surface of the guide plate 72 at the far end relative to the rotatable connection between the guide plate 72 and the inlet shell 52.

[0081] By guiding the transmission belt 791 through at least two guide wheels 79, the transmission belt 791 forms a preset transmission distribution trajectory between the guide plate 72 and the cover plate 71, so that the guide plate 72 can synchronously drive the cover plate 71 to rotate 90° during the rotation process.

[0082] Specifically, in the initial state, the cover plate 71 is arranged along the axial direction of the air intake pipe 2. When the guide plate 72 rotates, the transmission belt 791 changes the transmission direction under the guidance of the guide wheel 79 and transmits the rotational power of the guide plate 72 to the cover plate 71, so as to drive the cover plate 71 to gradually rotate to the state of being arranged radially along the air intake pipe 2, thereby realizing the switching of the attitude of the cover plate 71.

[0083] When the detection unit 4 detects a gas leak, the flow rate increases sharply. The guide plate 72 rotates under the drive of the drive unit, and then drives the cover plate 71 to rotate through the transmission belt 791 until the cover plate 71 overlaps the air inlet.

[0084] Preferably, the transmission belt 791 itself is elastic or a telescopic rod is embedded in the side of the transmission belt 791 near the guide plate 72, and a second spring is sleeved on the surface of the telescopic rod, with the two ends of the second spring respectively fixed to the two ends of the telescopic rod.

[0085] When the guide plate 72 rotates under the pressure of the flow rate within the gas detection range, the cover plate 71 does not rotate accordingly. At this time, the transmission belt 791 extends or the telescopic rod extends. When the telescopic rod extends, the second spring deforms, while the second coil spring does not deform.

[0086] The range of gas detection is the same as the range of normal ventilation.

[0087] When the gas leaks, the gas flow rate increases sharply, and the angle of rotation of the guide plate 72 driven by the drive unit tends to 180°. At this time, the transmission belt 791 itself is stretched to its limit length or the telescopic rod is stretched to its limit length, thereby driving the cover plate 71 to rotate as well, until the cover plate 71 overlaps and covers the air inlet. At this time, the guide plate 72 tends to be set along the axial direction of the air inlet pipe 2. During this process, the second coil spring deforms.

[0088] This invention is not limited to the embodiments described above. Any changes in shape or structure shall fall within the protection scope of this invention. The protection scope of this invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of this invention, but all such changes and modifications shall fall within the protection scope of this invention.

Claims

1. A gas detection device with ventilation function, comprising a detection unit (4) with gas detection function, wherein the detection unit (4) is disposed on the air intake pipe (2) of a ventilation fan (1), and a portion of the airflow flowing into the air intake pipe (2) is guided to the detection end of the detection unit (4) by a flow guiding component, characterized in that: The flow guiding component is located on one side of the inner cavity of the air intake pipe (2), and the air intake end of the flow guiding component is provided with a flow guiding component. The flow guiding component changes the introduced air flow rate according to the airflow velocity inside the air intake pipe (2). The higher the flow velocity, the more air flow rate enters the flow guiding component. After detecting a gas leak, the detection unit (4) controls the ventilation fan (1) to increase its speed; and as the flow velocity inside the air intake pipe (2) further increases, the diversion component moves toward a closed state under the action of airflow.

2. The gas detection device with ventilation function as described in claim 1, characterized in that: The flow guiding assembly includes a ring-shaped manifold (5), which is fitted around the air intake pipe (2). Multiple air intake shells (52) arranged in a ring array are connected to one side of the outer wall of the manifold (5). The end of the air intake shell (52) penetrates the side wall of the air intake pipe (2) and extends away from the ventilation fan (1). A guide shell (51) is connected to the outer wall of the other side of the manifold (5), and the guide shell (51) wraps around the detection end of the detection unit (4); A flow guide assembly is connected to one end of the inlet shell (52).

3. The gas detection device with ventilation function as described in claim 1, characterized in that: The flow-guiding component is a first flow-guiding component (6). The first flow-guiding component (6) includes a connecting shell (61). One end of the connecting shell (61) is connected to the outer wall of the inlet shell (52), and the other end of the connecting shell (61) is a circular air inlet port. A first flow-guiding part is provided on the air inlet port. The cross-sectional area of ​​the first flow-guiding part gradually increases from one side to the other to form a frustum-shaped shell structure. The side of the first flow-guiding part with a smaller cross-sectional area is connected to the air inlet port. An air inlet is formed on the side with a larger cross-sectional area of ​​the first drainage part. The air inlet can gradually increase as the gas flow rate in the air inlet pipe (2) increases. After the gas flow rate in the air inlet pipe (2) further increases, the first drainage part drives the air inlet port to move toward the closed state until it is closed.

4. The gas detection device with ventilation function as described in claim 3, characterized in that: The first flow guide includes a bearing shaft (62), and a frustum-shaped flow guide shell is fitted around the bearing shaft (62). The bearing shaft (62) is set on the central shaft of the air intake port. A guide block (63) is slidably sleeved on the surface of the bearing shaft (62). The guide block (63) is connected to the flow guide shell. When the air intake opening on the side with the larger cross-sectional area of ​​the flow guide shell is enlarged or reduced, the guide block (63) slides on the bearing shaft (62), thereby driving the sealing plate to move. The sealing plate can overlap the air intake port. The surface of the bearing shaft (62) is fitted with a first spring (69).

5. The gas detection device with ventilation function as described in claim 4, characterized in that: The air guide shell includes multiple support rods (65) rotatably connected to the air intake port, and two adjacent support rods (65) are connected by a fan-shaped air guide cover (66). The surface of the support rod (65) is rotatably connected to one end of the transmission rod (64), and the other end of the transmission rod (64) is rotatably connected to the guide block (63). The guide block (63) is fixedly connected to a sealing plate by a rod on the side near the air inlet port, and the sealing plate is slidably sleeved on the bearing shaft (62).

6. The gas detection device with ventilation function as described in claim 1, characterized in that: The flow-guiding component is a second flow-guiding component (7). The second flow-guiding component (7) includes a guide plate (72) rotatably connected to the air inlet of the flow-guiding component and located near the center of the air inlet pipe (2). A first coil spring is provided at the rotatable connection between the guide plate (72) and the inlet shell (52). The top of the air intake opening is rotatably connected to a cover plate (71) that can cover the air intake opening. A second coil spring is provided at the rotatable connection between the cover plate (71) and the inlet shell (52). The cover plate (71) is supported by the elastic force of the second coil spring and is arranged along the axial direction of the air intake pipe (2). The cover plate (71) and the guide plate (72) are connected in a transmission manner. It also includes a drive unit that is connected to the guide plate (72) for transmission. The drive unit is driven by the airflow that reaches a preset flow rate, which drives the guide plate (72) to rotate toward the center of the air intake pipe (2).

7. The gas detection device with ventilation function as described in claim 6, characterized in that: The drive unit includes a drive component and a transmission component that can trap airflow. The drive component is connected to the guide plate (72) via the transmission component. After being pushed by airflow with sufficient velocity, the drive component drives the guide plate (72) to rotate toward one side of the central region of the air intake pipe (2) via the transmission component.

8. The gas detection device with ventilation function as described in claim 7, characterized in that: The transmission component includes a connecting crossbar (73), one end of which is rotatably connected to the guide plate (72), and the other end is fixed to the slider (74). The slider (74) is slidably connected to the guide rail (75) arranged radially along the air intake pipe (2). Guide sleeves (76) are fixed on both sides of the guide rail (75). The guide sleeves (76) are slidably sleeved on the surface of the guide crossbar (77) arranged axially along the air intake pipe (2). The guide crossbar (77) is fixed on the outer wall of the inlet shell (52). The driving component includes a fixing rod (781) and a driving cover (78). One end of the fixing rod (781) is fixed to the guide rail (75), and the other end of the fixing rod (781) is fixed to the bowl-shaped driving cover (78).

9. The gas detection device with ventilation function as described in claim 6, characterized in that: Both sides of the guide plate (72) and the cover plate (71) are connected to each other by a transmission belt (791), and the transmission belt passes over at least one guide wheel (79) fixed on the outer wall of the inlet shell (52).

10. The gas detection device with ventilation function as described in claim 9, characterized in that: The transmission belt (791) itself is elastic or a telescopic rod is embedded on the side of the transmission belt (791) near the guide plate (72), and a second spring is sleeved on the surface of the telescopic rod.

Images