Air door position detection device for drying fan

Abstract

The present invention provides a damper position detection device for a drying fan, which belongs to the technical field of position detection, and includes a detection tube, a proximity switch, a driving member, a trigger block, a clamping member and a compression spring. A control hole is provided on the upper wall of the detection tube. The proximity switch is fixed at the lower end in the detection tube. The lower end of the driving member is slidably arranged in the detection tube, and the upper end slides through the upper wall of the detection tube and the leakage end is used to be fixedly connected to the damper. The trigger block is slidably arranged between the proximity switch and the driving member. Two clamping members are arranged at a relative interval, and the middle part of the clamping member is hinged to the driving member around a horizontal axis. The compression spring is arranged at the upper end between the two clamping members. The lower ends of the two clamping members slide downward to clamp the trigger block, and the two clamping members slide upward to release the trigger block at the lower ends of the two clamping members. The damper position detection device for a drying fan provided by the present invention solves the problem that the signal of the damper opening and the damper opening to the maximum position cannot be collected.

Description

Technical Field

[0001] The present invention belongs to the technical field of position detection, and more specifically, relates to a damper position detection device for a drying fan. Background Art

[0002] The drying fan of the cold rolling skin-pass mill is equipped with a damper, and the wind blown out by the damper is used to purge and cool the skin-pass liquid and surface water on the surface of the strip. According to the process requirements and the protection of the extreme action of the equipment, the program needs to collect the signal of the damper opening and the signal of the damper opening to the maximum position. Since the damper is located at a position where there are also tension roller equipment, a card plate, a hydraulic pipeline, etc., the action of the damper cannot be derived through transmission, etc., so there is no way to collect the signal of the damper opening and the signal of the damper opening to the maximum position in the existing technology. Summary of the invention

[0003] The object of the present invention is to provide a damper position detection device for a drying fan, aiming to solve the problem that the signal when the damper is opened and when the damper is opened to the maximum position cannot be collected.

[0004] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: to provide a damper position detection device for a drying fan, comprising a detection cylinder, a proximity switch, a driving member, a trigger block, a clamping member and a compression spring. The detection cylinder is used to be fixedly arranged relative to the damper of the drying fan, the axis of the detection cylinder is arranged vertically, and the upper wall of the detection cylinder is provided with a control hole with a trapezoidal longitudinal section and gradually decreasing outward. The proximity switch is fixedly arranged at the lower end in the detection cylinder. The lower end of the driving member is slidably arranged in the detection cylinder, and the upper end slides through the upper wall of the detection cylinder and the leaking end is used to be fixedly connected with the damper. The trigger block is slidably arranged in the detection cylinder and is located between the proximity switch and the driving member. The number of the clamping members is two and they are slidably arranged in the detection cylinder, the two clamping members are arranged relatively spaced, and the middle part of the clamping member is hinged with the driving member around the horizontal axis. The compression spring is arranged at the upper end between the two clamping members, and the two ends of the compression spring are used to press the upper ends of the two clamping members outward. The lower end of the clamping member slides downward with the driving member to squeeze the trigger block, so that the lower ends of the two clamping members rotate and then clamp the trigger block, and the upper end of the clamping member slides upward with the driving member to penetrate the control hole, so that the lower ends of the two clamping members rotate and then release the trigger block.

[0005] As another embodiment of the present application, a protruding clamping portion is fixedly provided on the opposite side of the clamping member, the lower ends of the two clamping portions are each provided with a first chamfer and the two first chamfers are arranged opposite to each other, and a vertically arranged clamping column is fixedly provided on the upper end of the trigger block, the clamping column and the space between the two first chamfers are aligned vertically, and the clamping column is used to be clamped by the inner side surfaces of the two clamping portions.

[0006] As another embodiment of the present application, a first limiting portion protruding radially outward along the clamping column is fixedly disposed on the upper end surface of the clamping column, and the first limiting portion is used to achieve axial limitation of the clamping portion when the two clamping portions clamp the clamping column.

[0007] As another embodiment of the present application, a horizontally arranged driving column is fixedly provided at the upper end of the inner side of the clamping member, a second limiting portion protruding radially outward along the driving column is fixedly provided at the middle portion of the driving column, the compression spring is sleeved on the two driving columns and the two ends of the compression spring respectively squeeze one of the second limiting portions.

[0008] As another embodiment of the present application, the driving member includes a driving block arranged in the detection cylinder and a driving rod penetrating the upper wall, the driving block is fixedly connected to the driving rod, and the leakage end of the driving rod is provided with a plurality of connection holes along the axial direction of the driving rod for fixed connection with the damper.

[0009] As another embodiment of the present application, a mounting piece is fixedly provided at the bottom end of the detection tube, and the mounting piece is provided with a vertically arranged fixing hole, and the fixing hole is used to fix the proximity switch.

[0010] As another embodiment of the present application, an air inlet is provided on the lower wall of the detection cylinder, and the air inlet is connected to a purge air source. A ventilation channel is provided in the detection cylinder, and one end of the ventilation channel is connected to the control hole, and the other end passes through the corresponding end of the driving member, the trigger block and the mounting member in sequence and then connects to the air inlet.

[0011] As another embodiment of the present application, the mounting member includes a first end cover, a first sleeve ring coaxial with the detection tube, a fixing plate and a second sleeve ring coaxial with the detection tube, which are arranged separately from top to bottom, and the middle part of the proximity switch is fixed on the fixing plate.

[0012] As another embodiment of the present application, the lower end of the inner surface of the detection cylinder has a limiting groove recessed inwardly along the radial direction of the detection cylinder, and the mounting member matches and fits with the limiting groove.

[0013] As another embodiment of the present application, the lower wall of the detection cylinder is separately arranged from the cylinder body of the detection cylinder, the bottom surface of the lower wall is abutted against a supporting rod, one end of the supporting rod is hinged to the cylinder body around a horizontal axis, and the other end of the supporting rod is connected to the cylinder body by means of a hasp lock.

[0014] The beneficial effect of the damper position detection device for a drying fan provided by the present invention is that compared with the prior art, the damper position detection device for a drying fan provided by the present invention has the following advantages: compared with the prior art, since the driving member is fixedly connected to the damper, when the damper is closed, the lower end of the clamping member slides downward with the driving member to squeeze the trigger block, and the lower ends of the two clamping members rotate and clamp the trigger block under the action of the rebound force of the compression spring; when the damper is opened, the two clamping members clamp the trigger block and slide upward, at which time the proximity switch sends a signal; when the upper end of the clamping member slides upward with the driving member and penetrates into the control hole, since the longitudinal section of the control hole is trapezoidal and gradually becomes smaller outward, the upper ends of the two clamping members will rotate inward, eventually causing the lower ends of the two clamping members to rotate outward and then release the trigger block, and the trigger block slides downward under the action of gravity, and at this time when the damper is opened to the maximum position, the proximity switch sends a signal, so the present invention solves the problem that the signal of the damper opening and the damper opening to the maximum position cannot be collected. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 A schematic diagram of the isometric structure of a damper position detection device for a drying fan provided by an embodiment of the present invention;

[0017] Figure 2 A schematic cross-sectional view of a damper position detection device for a drying fan provided by an embodiment of the present invention;

[0018] Figure 3 for Figure 2 Schematic diagram of the enlarged structure of the local A in FIG.

[0019] Figure 4 A schematic diagram of the axonometric structure of a detection cylinder in a damper position detection device for a drying fan provided in an embodiment of the present invention with the lower wall removed;

[0020] Figure 5 A schematic diagram of the axonometric structure of the lower wall of the damper position detection device for a drying fan provided by an embodiment of the present invention;

[0021] Figure 6 A schematic diagram of the isometric structure of a driving block in a damper position detection device for a drying fan provided by an embodiment of the present invention;

[0022] Figure 7A schematic diagram of the isometric structure of a driving rod in a damper position detection device for a drying fan provided in an embodiment of the present invention.

[0023] In the figure: 1, detection cylinder; 11, upper wall; 111, control hole; 12, lower wall; 121, air inlet; 122, wiring hole; 123, third set ring; 13, cylinder; 131, limit groove; 132, slideway; 2, proximity switch; 21, nut; 3, driving member; 31, driving block; 311, first mounting hole; 312, second mounting hole; 32, driving rod; 321, connecting hole; 4, trigger block; 41, support column; 411, clamp Tightening column; 412, first limiting portion; 42, sleeve block; 43, second chamfer; 5, clamping member; 51, clamping portion; 511, first chamfer; 52, driving column; 521, second limiting portion; 6, compression spring; 7, mounting member; 701, fixing hole; 704, air vent; 71, first end cover; 72, first sleeve ring; 73, fixing plate; 74, second sleeve ring; 8, supporting rod; 81, connecting groove; 9, buckle lock; 10, connecting plate. DETAILED DESCRIPTION

[0024] In order to make the technical problems, technical solutions and beneficial effects to be solved by 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.

[0025] Please also read Figures 1 to 4 , the damper position detection device for a drying fan provided by the present invention is now described. The damper position detection device for a drying fan comprises a detection cylinder 1, a proximity switch 2, a driving member 3, a trigger block 4, a clamping member 5 and a compression spring 6. The detection cylinder 1 is used to be fixedly arranged relative to the damper of the drying fan, the axis of the detection cylinder 1 is arranged vertically, and the upper wall 11 of the detection cylinder 1 is provided with a control hole 111 with a trapezoidal longitudinal section and gradually decreasing outward. The proximity switch 2 is fixedly arranged at the lower end in the detection cylinder 1. The lower end of the driving member 3 is slidably arranged in the detection cylinder 1, and the upper end slides through the upper wall 11 of the detection cylinder 1 and the leaking end is used for fixed connection with the damper. The trigger block 4 is slidably arranged in the detection cylinder 1 and is located between the proximity switch 2 and the driving member 3. There are two clamping members 5 and they are slidably arranged in the detection cylinder 1. The two clamping members 5 are arranged relatively spaced apart, and the middle part of the clamping member 5 is hinged to the driving member 3 around the horizontal axis. The compression spring 6 is arranged at the upper end between the two clamping members 5, and the two ends of the compression spring 6 are used to press the upper ends of the two clamping members 5 outward. The lower end of the clamping member 5 slides downward with the driving member 3 to press the trigger block 4, so that the lower ends of the two clamping members 5 rotate and clamp the trigger block 4, and the upper end of the clamping member 5 slides upward with the driving member 3 to penetrate the control hole 111, so that the lower ends of the two clamping members 5 rotate and release the trigger block 4.

[0026] In this embodiment, the detection tube 1 can be fixedly connected to a connection plate 10 , and fixedly connected to a wall or the like through the connection plate 10 .

[0027] Compared with the prior art, the damper position detection device for a drying fan provided by the present invention has a function that the driving member 3 is fixedly connected to the damper. Therefore, when the damper is closed, the lower end of the clamping member 5 slides downward with the driving member 3 to squeeze the trigger block 4. After the lower ends of the two clamping members 5 rotate, the trigger block 4 is clamped under the action of the rebound force of the compression spring 6. When the damper is opened, the two clamping members 5 clamp the trigger block 4 and slide upward. At this time, the proximity switch 2 sends a signal. When the upper end of the clamping member 5 slides upward with the driving member 3 and penetrates the control hole 111, since the longitudinal section of the control hole 111 is trapezoidal and gradually decreases outward, the upper ends of the two clamping members 5 will rotate inward, eventually causing the lower ends of the two clamping members 5 to rotate outward and then release the trigger block 4. The trigger block 4 slides downward under the action of gravity. At this time, when the damper is opened to the maximum position, the proximity switch 2 sends a signal. Therefore, the present invention solves the problem that the signals of the damper opening and the damper opening to the maximum position cannot be collected.

[0028] As a specific embodiment of the damper position detection device for a drying fan provided by the present invention, please refer to Figures 2 to 4 In order to realize that when the lower end of the clamping member 5 slides downward with the driving member 3 to squeeze the trigger block 4, the lower ends of the two clamping members 5 rotate and clamp the trigger block 4, a protruding clamping portion 51 is fixed on the opposite side of the clamping member 5, and the lower ends of the two clamping portions 51 are both provided with a first chamfer 511 and the two first chamfers 511 are arranged opposite to each other. A vertically arranged clamping column 411 is fixed on the upper end of the trigger block 4, and the space between the clamping column 411 and the two first chamfers 511 is aligned vertically, and the clamping column 411 is used to be clamped by the inner side surfaces of the two clamping portions 51. The clamping column 411 opens the two clamping portions 51 by squeezing the two first chamfers 511. When the clamping column 411 enters between the two clamping portions 51, the compression spring 6 compresses the upper ends of the two clamping members 5 to rotate outward, so the lower ends of the two clamping portions 51 will clamp the clamping column 411 inward. That is, the trigger block 4 is clamped after the lower ends of the two clamping members 5 rotate. In this embodiment, two slideways 132 may be further provided on the inner surface of the detection cylinder 1. The two slideways 132 are respectively used for the sliding of one of the clamping members 5, so that when the two clamping members 5 slide upward, the upper ends of the two clamping members 5 can accurately penetrate into the control hole 111, and when the two clamping members 5 slide downward, the lower ends of the two clamping members 5 accurately clamp the clamping column 411.

[0029] As a specific embodiment of the damper position detection device for a drying fan provided by the present invention, please refer to Figure 2The upper end surface of the clamping column 411 is fixed with a first limiting portion 412 protruding outward along the radial direction of the clamping column 411. The first limiting portion 412 is used to realize the axial limiting of the clamping portion 51 when the two clamping portions 51 clamp the clamping column 411, so as to increase the reliability of the trigger block 4 sliding upward with the clamping member 5, that is, to increase the reliability of the proximity switch 2 transmitting the signal. The first limiting portion 412 is used to open the two clamping portions 51. When the two clamping portions 51 move downward to the position of the clamping column 411, the two clamping portions 51 rotate inward to clamp the clamping column 411.

[0030] As a specific embodiment of the damper position detection device for a drying fan provided by the present invention, please refer to Figure 3 In order to achieve the two ends of the compression spring 6 squeezing the upper ends of the two clamping members 5 outward, a horizontally arranged driving column 52 is fixedly provided at the upper end of the inner side of the clamping member 5, and a second limiting portion 521 protruding radially outward along the driving column 52 is fixedly provided in the middle part of the driving column 52. The compression spring 6 is sleeved on the two driving columns 52 and the two ends of the compression spring 6 squeeze a second limiting portion 521 respectively.

[0031] As a specific embodiment of the damper position detection device for a drying fan provided by the present invention, please refer to Figure 2 , Figure 6 and Figure 7 The driving member 3 includes a driving block 31 disposed in the detection cylinder 1 and a driving rod 32 penetrating the upper wall 11. The driving block 31 is fixedly connected to the driving rod 32. The leakage end of the driving rod 32 is provided with a plurality of connection holes 321 for fixed connection with the damper along the axial direction of the driving rod 32. This structure is simple and easy to process, and the provision of a plurality of connection holes 321 allows the detection device to be applied to dampers of different dryers, and has a wide range of applications. In this embodiment, two first mounting holes 311 which penetrate radially outward can be provided on the end surface of the driving block 31, and the middle parts of the two clamping members 5 are respectively located in one of the first mounting holes 311. A horizontal second mounting hole 312 can be provided in the middle part of the driving block 31, and the two ends of the second mounting hole 312 are respectively connected to one of the first mounting holes 311. The middle part of the compression spring 6 is placed in the second mounting hole 312. When the two clamping members 5 clamp the trigger block 4, the bottom surface of the driving block 31 is used to abut and limit the top surface of the trigger block 4 to prevent the two clamping members 5 from damaging the lower end of the trigger block 4 which is not used to be clamped.

[0032] As a specific embodiment of the damper position detection device for a drying fan provided by the present invention, please refer to Figure 2, a mounting member 7 is fixedly provided at the bottom end of the detection tube 1, and a vertically arranged fixing hole 701 is provided in the mounting member 7, and the fixing hole 701 is used to fix the proximity switch 2. Placing the proximity switch 2 in the fixing hole 701 can prevent the proximity switch 2 from being damaged due to the extrusion or collision of the trigger block 4. In this embodiment, in order to further protect the proximity switch 2, the trigger block 4 includes a central metal support column 41 and a nylon set block 42 sleeved outside the support column 41, the support column 41 is fixedly connected to the set block 42, the upper end of the support column 41 extends outside the set block 42, and a section of the support column 41 located above the set block 42 is used to be set as a clamping column 411, and the lower surface of the support column 41 is used to contact the upper surface of the mounting member 7, which does not affect the use of the trigger block 4, and also reduces the weight of the trigger block 4, that is, it reduces the impact of the vibration of the trigger block 4 sliding downward and colliding with the mounting member 7 on the proximity switch 2.

[0033] As a specific embodiment of the damper position detection device for a drying fan provided by the present invention, please refer to Figure 1 , Figure 2 and Figure 5 , the ambient temperature near the detection tube 1 is high, which will affect the proximity switch 2, and iron powder and dust will enter the detection tube 1 from the upper control hole 111, thereby affecting the use of the device, which requires frequent wiping or replacement of the parts in the detection tube 1, and the work site for these works is high, the space is narrow, and the risk factor is high. In order to avoid the above-mentioned influence, an air inlet 121 is opened on the lower wall 12 of the detection tube 1, and the air inlet 121 is connected to a purge air source. A ventilation channel is provided in the detection tube 1, one end of the ventilation channel is connected to the control hole 111, and the other end passes through the corresponding end of the driving member 3, the trigger block 4 and the mounting member 7 in sequence and then connects to the air inlet 121. The high-pressure gas generated by the purge air source enters the detection tube 1 from the air inlet 121, and is discharged from the control hole 111 after passing through the ventilation channel. In this way, iron powder and dust can be prevented from entering the detection tube 1 from the upper control hole 111, and the ventilation channel can also reduce the temperature in the detection tube 1. In this embodiment, the purge gas source can be an air compressor, and the ventilation channel includes a plurality of ventilation holes 704 provided on the mounting member 7 and the trigger block 4, and the trigger block 4 is provided with a second chamfer 43 at both ends, and the second chamfer 43 at the lower end is used to leak out of the ventilation hole 704 of the mounting member 7. A wiring hole 122 can also be provided on the lower wall 12 of the detection cylinder 1, and the electrical connection line of the proximity switch 2 is sealed and extended out from the wiring hole 122.

[0034] As a specific embodiment of the damper position detection device for a drying fan provided by the present invention, please refer to Figure 2In order to facilitate the installation of the proximity switch 2, the mounting member 7 includes a first end cover 71, a first sleeve ring 72 coaxial with the detection tube 1, a fixing plate 73 and a second sleeve ring 74 coaxial with the detection tube 1, which are arranged separately from top to bottom. The middle part of the proximity switch 2 is fixed on the fixing plate 73, the proximity switch 2 is inserted into the fixing hole 701, and the proximity switch 2 is fixedly connected to the fixing plate 73 by two nuts 21 on the proximity switch 2.

[0035] As a specific embodiment of the damper position detection device for a drying fan provided by the present invention, please refer to Figure 2 Hezhi Figure 4 In order to facilitate the installation of the mounting member 7 , the lower end of the inner surface of the detection cylinder 1 has a limiting groove 131 which is recessed inwardly along the radial direction of the detection cylinder 1 , and the mounting member 7 is matched and fitted with the limiting groove 131 .

[0036] As a specific embodiment of the damper position detection device for a drying fan provided by the present invention, please refer to Figure 1 to Figure 2 The lower wall 12 of the detection tube 1 is separately arranged from the cylinder body 13 of the detection tube 1. The bottom surface of the lower wall 12 is abutted against a supporting rod 8. One end of the supporting rod 8 is hinged with the cylinder body 13 around a horizontal axis, and the other end of the supporting rod 8 is connected to the cylinder body 13 by means of a buckle lock 9. When the mounting member 7 needs to be installed, the first step is to disconnect the cylinder body 13 from the lower wall 12 through the buckle lock 9, and then rotate the supporting rod 8 downward and remove the lower wall 12; the second step is to place the mounting member 7 in the limiting groove 131, and then reset the lower wall 12; the third step is to rotate the supporting rod 8 upward to reset it; finally, the cylinder body 13 and the lower wall 12 are connected together through the buckle lock 9. In this embodiment, a third sleeve ring 123 coaxial with the detection cylinder 1 can be fixed on the upper surface of the lower wall 12, the outer surface of the third sleeve ring 123 is in contact with the limiting groove 131, and the upper surface of the third sleeve ring 123 is used to support the mounting member 7, which can facilitate the installation and positioning of the lower wall 12. In this embodiment, the buckle lock 9 is hinged to the cylinder 13 around the horizontal axis, and the lower surface of the supporting rod 8 is provided with a connecting groove 81 for connecting with the buckle lock 9.

[0037] 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. A damper position detection device for a drying fan, characterized in that: include: The detection cylinder is used to be fixedly arranged relative to the damper of the drying fan, the axis of the detection cylinder is arranged vertically, and the upper wall of the detection cylinder is provided with a control hole with a trapezoidal longitudinal section and gradually becoming smaller outwards; A proximity switch is fixedly arranged at the lower end of the detection tube; A driving member, the lower end of which is slidably disposed in the detection cylinder, the upper end of which slides through the upper wall of the detection cylinder and the leaking end of which is used to be fixedly connected to the damper; A trigger block is slidably disposed in the detection cylinder and is located between the proximity switch and the driving member; Two clamping members are slidably disposed in the detection barrel, the two clamping members are relatively spaced apart, and the middle part of the clamping member is hinged to the driving member around a horizontal axis; and A compression spring, arranged at the upper end between the two clamping members, the two ends of the compression spring being used to press the upper ends of the two clamping members outwards; The lower end of the clamping member slides downward with the driving member to squeeze the trigger block, so that the lower ends of the two clamping members rotate to clamp the trigger block, and the upper end of the clamping member slides upward with the driving member to penetrate the control hole, so that the lower ends of the two clamping members rotate to release the trigger block; A protruding clamping portion is fixedly provided on the opposite side of the clamping member, and the lower ends of the two clamping portions are both provided with a first chamfer and the two first chamfers are arranged opposite to each other. A vertically arranged clamping column is fixedly provided on the upper end of the trigger block, and the clamping column is aligned with the space between the two first chamfers up and down, and the clamping column is used to be clamped by the inner side surfaces of the two clamping portions; A horizontally arranged driving column is fixedly disposed at the upper end of the inner side of the clamping member, a second limiting portion protruding outwardly along the radial direction of the driving column is fixedly disposed in the middle of the driving column, the compression spring is sleeved on the two driving columns, and the two ends of the compression spring respectively squeeze one of the second limiting portions; When the damper is closed, the lower end of the clamping member slides downward with the driving member to squeeze the trigger block, and the lower ends of the two clamping members rotate and clamp the trigger block under the action of the rebound force of the compression spring. When the damper is opened, the two clamping members clamp the trigger block and slide upward. At this time, the proximity switch sends a signal. When the upper end of the clamping member slides upward with the driving member and penetrates into the control hole, since the longitudinal section of the control hole is trapezoidal and gradually decreases outward, the upper ends of the two clamping members will rotate inward, and finally cause the lower ends of the two clamping members to rotate outward and release the trigger block. The trigger block slides downward under the action of gravity. At this time, when the damper is opened to the maximum position, the proximity switch sends a signal.

2. The damper position detection device for a drying fan according to claim 1, characterized in that: A first limiting portion protruding outwardly in the radial direction of the clamping column is fixedly disposed on the upper end surface of the clamping column, and the first limiting portion is used to achieve axial limiting of the clamping portion when the two clamping portions clamp the clamping column.

3. The damper position detection device for a drying fan according to claim 1, characterized in that: The driving member includes a driving block arranged in the detection tube and a driving rod penetrating the upper wall, the driving block is fixedly connected to the driving rod, and the leakage end of the driving rod is provided with a plurality of connection holes for fixed connection with the damper along the axial direction of the driving rod.

4. The damper position detection device for a drying fan according to claim 1, characterized in that: A mounting piece is fixedly arranged at the bottom end of the detection cylinder. The mounting piece is provided with a vertically arranged fixing hole, and the fixing hole is used to fix the proximity switch.

5. The damper position detection device for a drying fan according to claim 4, characterized in that: An air inlet is provided on the lower wall of the detection cylinder, and the air inlet is connected to a purge air source. A ventilation channel is provided in the detection cylinder, and one end of the ventilation channel is connected to the control hole, and the other end passes through the corresponding end of the driving member, the trigger block and the mounting member in sequence and then connects to the air inlet.

6. The damper position detection device for a drying fan according to claim 5, characterized in that: The mounting member comprises a first end cover, a first sleeve ring coaxial with the detection tube, a fixing plate and a second sleeve ring coaxial with the detection tube, which are arranged separately from top to bottom in sequence. The middle part of the proximity switch is fixed on the fixing plate.

7. The damper position detection device for a drying fan according to claim 5, characterized in that: The lower end of the inner surface of the detection cylinder has a limiting groove which is recessed inwardly along the radial direction of the detection cylinder, and the mounting piece is matched and fitted with the limiting groove.

8. The damper position detection device for a drying fan according to claim 7, characterized in that: The lower wall of the detection cylinder is separately arranged from the cylinder body of the detection cylinder, the bottom surface of the lower wall is abutted with a supporting rod, one end of the supporting rod is hinged to the cylinder body around a horizontal axis, and the other end of the supporting rod is connected to the cylinder body by means of a buckle lock.

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