Dehumidifying device for air cover paper web outlet of paper machine

Abstract

The utility model relates to the technical field of paper machine dehumidification, in particular to a paper machine air cover paper web outlet dehumidification device which comprises an air suction cover assembly, an exhaust pipe and an exhaust fan, the air suction cover assembly and the exhaust fan are both connected with the exhaust pipe, the air suction cover assembly is communicated with the inlet end of the exhaust pipe, and the air suction cover assembly is communicated with the outlet end of the exhaust pipe. And the exhaust fan is communicated with the outlet end of the exhaust pipe. The negative pressure type air permeability detector overcomes the defect that in the prior art, moisture escaped from the air cover paper web outlet of the paper machine interferes with the detection result of the negative pressure type air permeability detector, so that the air permeability detection result of the paper machine is not accurate, and can be used for dehumidification at the air cover paper web outlet of the paper machine. The negative pressure type air permeability detector can prevent moisture escaped from a paper machine air cover paper web outlet from interfering with detection of the negative pressure type air permeability detector, and is beneficial to improving the accuracy of paper web air permeability detection.

Description

Technical Field

[0001] The utility model relates to the technical field of paper machine dehumidification, and more specifically, to a dehumidifying device for the paper web outlet of a paper machine hood. Background Art

[0002] The closed hood is the latest hood type for paper machines, which has the advantages of good airtightness, high drying efficiency, and environmental friendliness to the workshop environment. However, the closed hood is not completely enclosed, and it must have a certain width of paper web inlet and paper web outlet, so the problem of the escape of hot and humid air in the hood is inevitable. In actual production, since most papers have certain requirements for air permeability, an air permeability detector is usually set after the drying section of the paper machine to monitor the air permeability of the paper web. From the perspective of the utilization efficiency of the workshop space, the installation position of the air permeability detector is not far from the paper web outlet of the hood, and the hot and humid air in the hood will reach the position of the air permeability detector as the paper web moves backward.

[0003] The air permeability detector is divided into a positive pressure type air permeability detector and a negative pressure type air permeability detector. Among them, the positive pressure type air permeability detector blows air from the inside to the outside with the detection head, and the negative pressure type air permeability detector sucks air from the outside to the inside. The negative pressure type on-line air permeability detector for paper web is widely used because of its high detection accuracy and strong sensitivity. The detection principle of the negative pressure type air permeability detector is to calculate the air permeability of the paper web by measuring the volume of air passing through the sensor within a unit time under a certain pressure difference. If the air humidity and temperature at the suction place are relatively high, the sucked air will change in volume due to factors such as temperature reduction and water vapor condensation in the detector, which will lead to deviation of the detection result. Therefore, the moisture escaping from the paper web outlet of the paper machine hood will interfere with the detection of the negative pressure type air permeability detector, resulting in inaccurate detection results of the air permeability of the paper web and bringing troubles to the paper machine production process. Content of the Utility Model

[0004] Aiming at the problem that the moisture escaping from the paper web outlet of the paper machine hood in the above-mentioned prior art will interfere with the detection result of the negative pressure type air permeability detector, resulting in inaccurate detection results of the air permeability of the paper web, the utility model provides a dehumidifying device for the paper web outlet of a paper machine hood, which can remove the moisture escaping from the paper web outlet of the paper machine hood and avoid the interference of the moisture on the detection of the negative pressure type air permeability detector.

[0005] In order to solve the above technical problems, the technical solution provided by the utility model is:

[0006] A dehumidifying device for the paper web outlet of a paper machine hood, comprising an air suction hood assembly, an exhaust duct and an exhaust fan. The air suction hood assembly and the exhaust fan are both connected to the exhaust duct. The air suction hood assembly is communicated with the inlet end of the exhaust duct, and the exhaust fan is communicated with the outlet end of the exhaust duct.

[0007] In the above technical solution, the dehumidifying device is arranged between the outlet of the paper machine hood paper web and the negative pressure air permeability detector. During implementation, the air inlet of the air suction hood assembly is close to the outlet of the paper machine hood paper web, and the air extraction direction of the air suction hood assembly forms a certain angle with the paper web surface. Then, the exhaust fan operates to form a negative pressure in both the exhaust duct and the air suction hood assembly, so as to suck away the moisture escaping from the outlet of the paper machine hood paper web, thereby avoiding the interference of this moisture on the detection of the negative pressure air permeability detector at the outlet of the paper machine hood paper web.

[0008] Preferably, it further includes an angle adjustment assembly for adjusting the air extraction direction of the air suction hood assembly. By adjusting the air extraction direction of the air suction hood assembly, the discharge direction and speed of the moisture can be controlled more precisely, so that the moisture at the outlet of the paper machine hood paper web can be effectively sucked out quickly and evenly, improving the dehumidification efficiency.

[0009] Preferably, the angle adjustment assembly includes a guide member and a fastening assembly. The guide member is connected to the air suction hood assembly, and an arc-shaped guide groove is provided on the guide member; a soft connection ring is provided at the edge of the inlet end of the air suction hood assembly. One end edge of the soft connection ring is connected to the edge of the inlet end of the air suction hood assembly, and the other end edge of the soft connection ring is connected with a swing frame; the fastening assembly includes a fastening knob and a guide rod. The guide member is located between the fastening knob and the swing frame. One end of the guide rod is connected to the fastening knob, and the other end passes through the guide groove and is threadedly connected to the swing frame. In the initial state, the fastening knob is in a tightened state, and the swing frame and the guide member remain relatively fixed. The air extraction direction of the air suction hood assembly is adjusted by adjusting the swing angle of the swing frame. During implementation, loosen the fastening knob to release the connection between the swing frame and the guide member, so that the guide rod can slide along the guide groove; then swing the swing frame, the guide rod slides along the guide groove, and at the same time the soft connection ring deforms, thereby realizing the adjustment of the swing angle of the swing frame; after determining the swing angle of the swing frame, tighten the fastening knob to fix the swing angle of the swing frame.

[0010] Preferably, the swing angle of the swing frame is between -5° and +5°. Within this angle range, the suction force and suction duration can be minimized to improve the dehumidification efficiency and speed.

[0011] Preferably, a filter plate is provided at the inlet of the swing frame, and a plurality of ventilation holes are provided on the filter plate. The filter plate acts as a barrier to prevent dust, fibers or large foreign objects from entering the air suction hood assembly, which helps to reduce the maintenance and cleaning of the device and avoid reducing the dehumidification efficiency.

[0012] Preferably, the diameter of the ventilation hole is between 8 mm and 12 mm. In this aperture range, larger particulate matters in the air, such as dust, fibers, and hair, can be effectively filtered. Moreover, within this aperture range, the ventilation effect and filtration efficiency can be balanced, without overly blocking the air flow, maintaining the normal working pressure and air volume of the dehumidifying nozzle, thereby ensuring the stable operation of the device.

[0013] Preferably, it further includes a height adjustment component. The height adjustment component includes a screw rod, a height limiting member, and an adjustment knob. One end of the screw rod is connected to the air suction hood component. The adjustment knob is threadedly connected to the screw rod, and the height limiting member abuts against the bottom end of the adjustment knob. A longitudinal telescopic portion is provided on the exhaust duct, and the axis of the longitudinal telescopic portion extends along the vertical direction. During implementation, the adjustment knob is rotated, causing the adjustment knob to move along the vertical direction relative to the screw rod. Since the height position of the adjustment knob is restricted by the height limiting member, when the adjustment knob is rotated, the height position of the adjustment knob remains unchanged, and the screw rod moves up and down, thereby driving the air suction hood component to move up and down. At the same time, the longitudinal telescopic portion expands and contracts in the vertical direction. Such a height adjustment component facilitates the staff to quickly manually adjust the height of the air suction hood component, and its structure is simple, with a relatively high adjustment accuracy, which is beneficial to accurately adjust the position of the air suction hood component and optimize the dehumidification process.

[0014] Preferably, at least two groups of the height adjustment components are provided, and at least two groups are respectively located on opposite sides of the air suction hood component, so that the air suction hood component can maintain a stable state when adjusting the height. Two groups of the angle adjustment components are provided, and the two groups of angle adjustment components are respectively located on opposite sides of the air suction hood component, so that the swing frame can maintain a stable state when adjusting the angle.

[0015] Preferably, the air suction hood component includes at least two trapezoidal hood bodies connected in sequence along the horizontal direction. An air outlet is provided at the top end of the trapezoidal hood body. A first inclined surface and a second inclined surface are respectively provided on opposite sides of the trapezoidal hood body. The distance between the top ends of the first inclined surface and the second inclined surface is less than the distance between the other ends of the two. The exhaust duct includes a main pipe, and at least two branch pipes are provided on the main pipe. The air inlet ends of the branch pipes are connected to the air outlets one by one, and the longitudinal telescopic portions are provided on all the branch pipes. The provision of the first inclined surface and the second inclined surface can guide the air flow to the air outlet at the top end of the trapezoidal hood body, reducing the resistance during air flow, thereby improving the dehumidification efficiency. Moreover, the provision of the first inclined surface and the second inclined surface can also reduce the noise generated by the collision between the turbulence and the air.

[0016] Preferably, a vacuum gauge is further included. The air vent pipe of the vacuum gauge communicates with the inner cavity of the air suction hood assembly, and the dial of the vacuum gauge is arranged outside the air suction hood assembly; air valves are provided on each branch pipe. When the negative pressure in the air suction hood assembly enters the air vent pipe in the vacuum gauge, the air vent pipe will bend more due to the negative pressure. This bending drives the pointer of the vacuum gauge to move through a lever and a gear mechanism, etc., and finally indicates the vacuum degree on the dial of the vacuum gauge. The staff adjusts the operating parameters of the exhaust fan, the opening degree of the air valve, the height of the air suction hood assembly, and the swing angle of the swing frame by observing the vacuum degree displayed on the vacuum gauge, so as to optimize the vacuum degree in the air suction hood assembly. This can ensure that the dehumidification device operates in the best working state and improve the dehumidification efficiency. Moreover, when the dehumidification device operates abnormally, such as when the pressure is too high or in other emergency situations, the air valve can play an emergency closing role to ensure the safety of operation.

[0017] Advantages of the utility model:

[0018] (1) This device can be used for dehumidification at the paper web outlet of the paper machine hood, which can avoid the interference of the moisture escaping from the paper web outlet of the paper machine hood to the detection of the negative pressure air permeability detector, and is beneficial to improving the accuracy of the paper web air permeability detection.

[0019] (2) The angle adjustment component is provided to adjust the swing angle of the swing frame, thereby adjusting the direction and speed of absorbing moisture, and can effectively suck away the moisture escaping from the paper web outlet of the paper machine hood quickly and evenly, improving the dehumidification efficiency; at the same time, the height adjustment component is provided to adjust the height of the air suction hood assembly, optimizing the dehumidification process; the height of the air suction hood assembly can be adjusted by screwing the adjustment knob in the height adjustment component, with simple and fast operation and high adjustment accuracy.

[0020] (3) A filter plate is provided at the inlet of the swing frame, which can prevent dust, fibers or large foreign objects from entering the air suction hood assembly, helping to reduce the maintenance and cleaning of this device and avoiding reducing the dehumidification efficiency.

[0021] (4) The air suction hood assembly includes a trapezoidal cover body, and a first inclined surface and a second inclined surface are provided on the trapezoidal cover body, which can guide the air flow to the air outlet at the top of the trapezoidal cover body, reduce the resistance during the air flow, thereby improving the dehumidification efficiency and reducing the noise during the dehumidification process.

[0022] (5) The air valve and the vacuum gauge are provided. The vacuum degree in the air suction hood assembly is displayed through the vacuum gauge, which is convenient for the staff to adjust the operating parameters of the exhaust fan, the height of the air suction hood assembly, and the swing angle of the swing frame according to the vacuum degree, ensuring that the dehumidification device operates in the best working state and improving the dehumidification efficiency. Description of the drawings

[0023] Figure 1It is a schematic structural diagram of a dehumidifying device for the paper web outlet of a paper machine hood;

[0024] Figure 2 It is a schematic structural diagram of a height adjustment component;

[0025] Figure 3 It is a schematic structural diagram of an angle adjustment component.

[0026] In the attached drawings: 1 - air suction hood assembly; 101 - trapezoidal hood body; 1011 - first inclined surface; 1012 - second inclined surface; 1013 - air outlet; 2 - exhaust duct; 201 - main duct; 202 - branch duct; 2021 - longitudinal telescopic part; 3 - connecting piece; 4 - screw; 5 - height limiting piece; 6 - adjusting knob; 7 - guiding piece; 701 - arc-shaped guiding groove; 8 - soft connecting ring; 9 - swinging frame; 10 - fastening knob; 11 - air valve; 12 - vacuum gauge. Detailed implementation manners

[0027] The attached drawings are only for illustrative purposes and should not be construed as a limitation to this patent; for better illustrating this embodiment, some components in the attached drawings will be omitted, enlarged or reduced, which do not represent the dimensions of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the attached drawings may be omitted. The positional relationships described in the attached drawings are only for illustrative purposes and should not be construed as a limitation to this patent.

[0028] In the attached drawings of the embodiments of the present utility model, the same or similar reference numerals correspond to the same or similar components; in the description of the present utility model, it should be understood that if there are terms such as "upper", "lower", "left", "right", "long", "short", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the attached drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationships in the attached drawings are only for illustrative purposes and should not be construed as a limitation to this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0029] The technical solutions of the present utility model will be further specifically described below through specific embodiments and in combination with the attached drawings:

[0030] Embodiment 1

[0031] As Figure 1 shown, a dehumidifying device for the paper web outlet of a paper machine hood includes an air suction hood assembly 1, an exhaust duct 2 and an exhaust fan (not shown in the figure). The air suction hood assembly 1 and the exhaust fan are both connected to the exhaust duct 2. The air suction hood assembly 1 is communicated with the inlet end of the exhaust duct 2, and the exhaust fan is communicated with the outlet end of the exhaust duct 2.

[0032] Working principle or process of this embodiment: The dehumidification device is arranged between the outlet of the paper web in the paper machine hood and the negative pressure air permeability detector. During implementation, the air inlet of the air suction hood assembly 1 is close to the outlet of the paper web in the paper machine hood, and the air extraction direction of the air suction hood assembly 1 forms a certain angle with the surface of the paper web. Then, the exhaust fan operates, creating negative pressure in both the exhaust duct 2 and the air suction hood assembly 1, thereby sucking away the moisture escaping from the outlet of the paper web in the paper machine hood, thus preventing this moisture from interfering with the detection of the negative pressure air permeability detector at the outlet of the paper web in the paper machine hood.

[0033] Beneficial effects of this embodiment: This device is used for dehumidification at the outlet of the paper web in the paper machine hood, which can prevent the moisture escaping from the outlet of the paper web in the paper machine hood from interfering with the detection of the negative pressure air permeability detector, and is beneficial to improving the accuracy of the air permeability detection of the paper web.

[0034] Embodiment 2

[0035] Based on Embodiment 1, as Figures 1 to 3 shown, it further includes an angle adjustment component, which is used to adjust the air extraction direction of the air suction hood assembly 1. By adjusting the air extraction direction of the air suction hood assembly 1, the discharge direction and speed of the moisture can be more precisely controlled, so that the moisture at the outlet of the paper web in the paper machine hood can be effectively sucked out quickly and evenly, improving the dehumidification efficiency.

[0036] Specifically, the angle adjustment component includes a guide member 7 and a fastening component. The guide member 7 is connected to the air suction hood assembly 1, and an arc-shaped guide groove 701 is provided on the guide member 7; a soft connection ring 8 is provided at the edge of the inlet end of the air suction hood assembly 1. The soft connection ring 8 is made of rubber. One edge of the soft connection ring 8 is connected to the edge of the inlet end of the air suction hood assembly 1, and the other edge of the soft connection ring 8 is connected to a swing frame 9; the fastening component includes a fastening knob 10 and a guide rod (not shown in the figure). The guide member 7 is located between the fastening knob 10 and the swing frame 9. One end of the guide rod is connected to the fastening knob 10, and the other end passes through the arc-shaped guide groove 701 and is threadedly connected to the swing frame 9. In the initial state, the fastening knob 10 is in a tightened state, and the swing frame 9 remains relatively fixed to the guide member 7. The air extraction direction of the air suction hood assembly 1 is adjusted by adjusting the swing angle of the swing frame 9. During implementation, loosen the fastening knob 10 to release the connection between the swing frame 9 and the guide member 7, so that the guide rod can slide along the arc-shaped guide groove 701; then swing the swing frame 9, the guide rod slides along the arc-shaped guide groove 701, and at the same time the soft connection ring 8 deforms, thus realizing the adjustment of the swing angle of the swing frame 9; after determining the swing angle of the swing frame 9, tighten the fastening knob 10 again to fix the swing angle of the swing frame 9.

[0037] Specifically, the swing angle of the swing frame 9 is between -5° and +5°, that is, the arc-shaped guide groove 701 enables the swing frame 9 to swing ±5°. Within this angle range, the suction force and suction duration can be minimized, and the dehumidification efficiency and speed can be improved.

[0038] Further, a filter plate (not shown in the figure) is provided at the inlet of the swing frame 9, and a plurality of ventilation holes are formed in the filter plate. The filter plate serves as a barrier to prevent dust, fibers, or large foreign objects from entering the air suction hood assembly 1, which helps reduce the maintenance and cleaning of the device and avoid reducing the dehumidification efficiency.

[0039] Further, the diameter of the ventilation holes is 10 mm, and the opening ratio is 38%. At this aperture and opening ratio, larger particulate matters in the air, such as dust, fibers, and hair, can be effectively filtered. Moreover, it can balance the ventilation effect and filtration efficiency, will not overly block the air flow, maintain the normal working pressure and air volume of the dehumidification nozzle, and thus ensure the stable operation of the device.

[0040] Further, a height adjustment component is further included. The height adjustment component includes a connecting member 3, two screw rods 4, a height limiting member 5, and two adjustment knobs 6. The connecting member 3 is connected to the air suction hood assembly 1, and one end of each screw rod 4 is connected to the connecting member 3, that is, one end of the screw rod 4 is connected to the air suction hood assembly 1 through the connecting member 3; the other ends of the screw rods pass through the height limiting member 5, and the adjustment knobs 6 are threadedly connected to the screw rods 4 one by one, and the height limiting member 5 abuts against the bottom ends of the two adjustment knobs 6 at the same time; a longitudinal telescopic portion 2021 is provided on the exhaust duct 2, and the axis of the longitudinal telescopic portion 2021 extends along the vertical direction. Specifically, the longitudinal telescopic portion 2021 is a telescopic hose section. During implementation, the adjustment knob 6 is rotated, so that the adjustment knob 6 moves along the vertical direction relative to the screw rod 4. Since the height position of the adjustment knob 6 is restricted by the height limiting member 5, when the adjustment knob 6 is rotated, the height position of the adjustment knob 6 remains unchanged, and the screw rod 4 moves up and down, thereby driving the connecting member 3 and the air suction hood assembly 1 to move up and down together, and at the same time, the longitudinal telescopic portion 2021 expands and contracts in the vertical direction. Such a height adjustment component facilitates the staff to quickly manually adjust the height of the air suction hood assembly 1, has a simple structure, a relatively high distance adjustment accuracy, is beneficial to accurately adjust the position of the air suction hood assembly 1, and optimizes the dehumidification process.

[0041] Specifically, two groups of height adjustment components are provided, and the two groups of height adjustment components are respectively located on the opposite sides of the air suction hood assembly 1, so that the air suction hood assembly 1 can maintain a stable state when adjusting the height; two groups of angle adjustment components are provided, and the two groups of angle adjustment components are respectively located on the opposite sides of the air suction hood assembly 1, so that the swing frame 9 can maintain a stable state when adjusting the angle.

[0042] Other features, working principles, and beneficial effects of this embodiment are the same as those of Embodiment 1.

[0043] Embodiment 3

[0044] Based on Embodiment 2, as Figure 1 shown, the air suction hood assembly 1 includes two trapezoidal hood bodies 101 that are distributed and connected along the horizontal direction. An air outlet 1013 is provided at the top end of the trapezoidal hood body 101. A first inclined surface 1011 and a second inclined surface 1012 are respectively provided on the opposite sides of the trapezoidal hood body 101. The distance between the top ends of the first inclined surface 1011 and the second inclined surface 1012 is less than the distance between the other ends of the two; the exhaust duct 2 includes a main duct 201 arranged horizontally. Two branch ducts 202 are provided on the main duct 201. The axis of the branch duct 202 is perpendicular to the axis of the main duct 201. The air inlet ends of the branch ducts 202 are connected to the air outlet 1013 one by one. Longitudinal telescopic parts 2021 are provided on the branch ducts 202. The first inclined surface 1011 and the second inclined surface 1012 are provided to guide the air flow to the air outlet 1013 at the top end of the trapezoidal hood body 101, reduce the resistance during air flow, and thus improve the dehumidification efficiency. Moreover, the first inclined surface 1011 and the second inclined surface 1012 are provided to reduce the noise generated by the collision of turbulence and air.

[0045] Furthermore, it further includes a vacuum gauge 12. The ventilation pipe of the vacuum gauge 12 is communicated with the inner cavity of the air suction hood assembly 1. The dial of the vacuum gauge 12 is arranged outside the air suction hood assembly 1; air valves 11 are provided on the branch ducts 202. Specifically, two vacuum gauges 12 are provided and are respectively arranged outside the two trapezoidal hood bodies 101. The ventilation pipes of the two vacuum gauges 12 are respectively communicated with the inner cavities of the two trapezoidal hood bodies 101. When the negative pressure in the trapezoidal hood body 101 enters the ventilation pipe in the vacuum gauge 12, the ventilation pipe will be more bent due to the negative pressure. This bending drives the pointer of the vacuum gauge 12 to move through a lever and gear mechanism, etc., and finally indicates the vacuum degree on the dial of the vacuum gauge 12. The staff adjusts the operating parameters of the exhaust fan, the opening degree of the air valve 11, the height of the air suction hood assembly 1, and the swing angle of the swing frame 9 by observing the vacuum degree displayed by the vacuum gauge 12, so as to optimize the vacuum degree in the air suction hood assembly 1. This can ensure that the dehumidification device operates in the best working state and improve the dehumidification efficiency. Moreover, when the dehumidification device operates abnormally, such as when the pressure is too high or in other emergency situations, the air valve 11 can play an emergency closing role to ensure the safety of operation.

[0046] Other features, working principles, and beneficial effects of this embodiment are the same as those of Embodiment 2.

[0047] Obviously, the above embodiments of the present utility model are merely examples for clearly illustrating the present utility model, rather than limitations on the implementation manners of the present utility model. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description, and it is not necessary and impossible to enumerate all implementation manners here. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the claims of the present utility model.

Claims

1. A paper machine air hood paper web outlet dehumidification device, characterized in that: The invention comprises an air suction hood assembly (1), an exhaust pipe (2) and an exhaust fan, wherein the air suction hood assembly (1) and the exhaust fan are both connected to the exhaust pipe (2), the air suction hood assembly (1) is connected to the inlet end of the exhaust pipe (2), and the exhaust fan is connected to the outlet end of the exhaust pipe (2).

2. A paper machine air hood paper web outlet dehumidification device according to claim 1, characterized in that: It also comprises an angle adjustment component, which is used to adjust the air suction direction of the air suction hood component (1).

3. A paper machine air hood paper web outlet dehumidification device according to claim 2, characterized in that: The angle adjustment assembly comprises a guide member (7) and a fastening assembly, wherein the guide member (7) is connected to the air suction cover assembly (1), and an arc-shaped guide groove (701) is provided on the guide member (7); a soft connecting ring (8) is provided at the inlet end edge of the air suction cover assembly (1), one end edge of the soft connecting ring (8) is connected to the inlet end edge of the air suction cover assembly (1), and the other end edge of the soft connecting ring (8) is connected to a swing frame (9); the fastening assembly comprises a fastening knob (10) and a guide rod, wherein the guide member (7) is located between the fastening knob (10) and the swing frame (9), one end of the guide rod is connected to the fastening knob (10), and the other end of the guide rod is threadedly connected to the swing frame (9) after passing through the arc-shaped guide groove (701).

4. A paper machine air hood paper web outlet dehumidification device according to claim 3, characterized in that: The swing angle of the swing frame is between -5° and +5°.

5. The paper machine air hood paper web outlet dehumidification device according to claim 3, characterized in that: A filter plate is provided at the inlet of the swing frame (9), and a plurality of ventilation holes are provided on the filter plate.

6. A paper machine air hood paper web outlet dehumidification device according to claim 5, characterized in that: The diameter of the ventilation hole is between 8 mm and 12 mm.

7. The paper machine air hood paper web outlet dehumidification device according to claim 3, characterized in that: The invention also comprises a height adjustment component, which comprises a screw rod (4), a height limiting member (5) and an adjusting knob (6), one end of the screw rod (4) is connected to the air suction hood component (1), the adjusting knob (6) is threadedly connected to the screw rod (4), and the height limiting member (5) abuts against the bottom end of the adjusting knob (6); the exhaust pipe (2) is provided with a longitudinal telescopic portion (2021), and the axis of the longitudinal telescopic portion (2021) extends along the vertical direction.

8. The paper machine air hood paper web outlet dehumidification device according to claim 7, characterized in that: The height adjustment components are provided in at least two groups, and at least two groups are respectively located on two opposite sides of the air suction hood component (1); the angle adjustment components are provided in two groups, and the two groups of angle adjustment components are respectively located on two opposite sides of the air suction hood component (1).

9. The paper machine air hood paper web outlet dehumidification device according to claim 7, characterized in that: The air suction hood assembly (1) comprises at least two trapezoidal hood bodies (101) connected in sequence along a horizontal direction, an air outlet (1013) being provided at the top end of the trapezoidal hood body (101), a first inclined surface (1011) and a second inclined surface (1012) being provided on opposite sides of the trapezoidal hood body (101), respectively, the distance between the top end of the first inclined surface (1011) and the top end of the second inclined surface (1012) being smaller than the distance between the other ends thereof; the exhaust duct (2) comprises a main duct (201), at least two branch ducts (202) being provided on the main duct (201), the air inlet ends of the branch ducts (202) being connected one by one to the air outlet (1013), and the longitudinal telescopic portion (2021) being provided on each of the branch ducts (202).

10. A paper machine air hood paper web outlet dehumidification device according to claim 9, characterized in that: It also comprises a vacuum gauge (12), the ventilation pipe of the vacuum gauge (12) being in communication with the inner cavity of the air suction hood assembly (1), and the dial of the vacuum gauge (12) being arranged outside the air suction hood assembly (1); and air valves (11) are arranged on each of the branch pipes (202).

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