Online automatic decoking device for high-temperature camera in furnace

Abstract

The online automatic decoking device comprises a furnace body, a hole is formed in the inner wall of the furnace body, an embedded part is arranged in the hole, a base is arranged at one end of the embedded part, and the base is sequentially connected with a track box and a track power box; the track box is internally provided with a track for carrying a camera mirror rod to stretch out and draw back; a high-temperature-resistant camera is arranged below the track box in parallel, and the high-temperature-resistant camera is connected with a track in the track box through a fixing support; the outer side of the high-temperature-resistant camera is sleeved with an inner lens cone, the outer side of the inner lens cone is sleeved with a rotatable outer sleeve, and the end of the outer sleeve is provided with a decoking device capable of rotating along with the outer sleeve. According to the utility model, online continuous coke cleaning is realized through the rotatable outer sleeve and the coke cleaning device, and meanwhile, the blowing gas is introduced into the interlayer of the inner lens cone and the outer sleeve, so that the coking speed and the cooling effect at the front end of the lens rod can be further reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of furnace combustion monitoring, and particularly relates to an online automatic coking removal device for a high-temperature camera in a furnace. Background Technique

[0002] High-temperature resistant cameras are important equipment for industrial high-temperature heat treatment equipment such as waste incinerators, biomass boilers, pulverized coal furnaces, glass furnaces, and rotary kilns. They are used to observe the operating conditions such as the flame in the furnace, the state of materials, and coking on the furnace wall. They need to work in complex environments such as high temperature, high dust, and variable working conditions for a long time. Under common working conditions, the temperature in the furnace can reach 1000 - 1600 °C, and the dust concentration is 1 - 100 g / Nm 3 , and the camera in the furnace is prone to ash accumulation and coking during long-term operation, resulting in problems such as blurred vision and reduced field of view. Therefore, frequent maintenance is required, but this will increase the risk of equipment reliability and operating costs.

[0003] Coking refers to the situation in the boiler furnace where most of the ash in the fuel melts into a liquid or soft state at high temperatures. When these molten ash particles leave the flame and contact the heating surface, furnace wall, or other attachments, they adhere to the attachments due to cooling. Over time, more and more cokes accumulate, and finally solid coking is formed. In the prior art, the problem of the high-temperature resistance of the camera is mainly solved by relying on compressed air or water cooling. However, the coking problem has always been the biggest problem that plagues the long-term stable operation of the high-temperature resistant camera in the furnace. The existing methods generally use compressed air blowing and simple coking removal devices for coking removal, or manual coking removal at regular intervals, but the effects are all average, and it is impossible to achieve online continuous and efficient coking removal.

[0004] CN201706528U discloses a lens protection sleeve design of a double-layer annular gap sleeve for a biomass furnace, which can provide double-channel compressed air for the front section of the lens to form a double-layer blowing protection for the light inlet hole. However, this scheme fails to solve the coking removal problem, only slowing down the influence speed of coking on the vision. Under long-term operation, the outermost sleeve will still accumulate ash and coking, affecting the vision.

[0005] CN115046220A discloses a sleeve-type slag removal pipe design. A slag removal pipe is sleeved on the slag pushing pipe, and the slag removal pipe can slide horizontally along the lens rod freely and can extend into the furnace during operation for online coking removal. However, its disadvantage is that the slag removal pipe is a flat pipe, which can remove the coke blocks around the lens rod, but cannot remove the coking at the front end of the lens rod, especially around the light inlet hole. Therefore, it still cannot solve the problem of coking affecting the vision.

[0006] CN217737935U provides an offline coke cleaning design. When the camera lens rod exits the furnace chamber, a flat coke cleaning block is used to clean the coke deposition on the front side of the camera under the push of a hydraulic mechanism. The device can be designed to have the functions of automatic control of actions and strokes. The disadvantage of this solution is that it can only clean coke offline, and the coke cleaning range is only on one side of the camera light inlet hole, and it is impossible to achieve online and circumferential coke cleaning. Summary of the Invention

[0007] In view of the deficiencies of the prior art, the present invention provides an online automatic coke cleaning device for a high-temperature camera in a furnace.

[0008] The present invention is realized through the following technical solutions:

[0009] An online automatic coke cleaning device for a high-temperature camera in a furnace, comprising a furnace body. A hole is opened on the inner wall of the furnace body, and an embedded part is provided in the hole. One end of the embedded part exposed from the inner wall of the furnace body is provided with a base, and the base is sequentially connected to a track box and a track power box; a track for telescoping the camera lens rod is provided in the track box; a high-temperature resistant camera is arranged in parallel below the track box, and the high-temperature resistant camera is connected to the track in the track box through a fixed bracket;

[0010] The high-temperature resistant camera includes a telescopable camera lens rod and an associated sensor box. A camera sensor is provided in the sensor box; one end of the camera lens rod is connected to the camera sensor. An inner lens barrel is provided on the outer circumference of the rod body of the camera lens rod, and a rotatable outer sleeve is sleeved on the outer side of the barrel of the inner lens barrel; the inner lens barrel includes an inner lens barrel fixed section, an inner lens barrel detachable section, and an inner lens barrel front end that are sequentially connected to the sensor box. The inner lens barrel fixed section is connected to the fixed bracket; the outer sleeve is sleeved on the outer side of the inner lens barrel detachable section; the outer sleeve includes an outer sleeve fixed section and an outer sleeve movable section. The outer sleeve fixed section is fixed to the inner lens barrel detachable section. An activity buckle is provided between the outer sleeve movable section and the outer sleeve fixed section, and the outer sleeve movable section is restricted from lateral movement by the activity buckle; a raised sealing structure is provided at the joint of the outer sleeve movable section and the outer sleeve fixed section; a ring gear is provided on the outer circumference of the outer sleeve movable section, and the ring gear is connected to a motor through a transmission gear. The outer sleeve movable section can achieve a rotational movement under the drive of the ring gear driven by the motor, and the rotation center is the center line of the camera lens rod; the end of the outer sleeve movable section is a flat head structure, which is flush with the straight pipe end of the inner lens barrel detachable section; a strip-shaped coke cleaning scraper is provided at the end of the outer sleeve movable section, and the coke cleaning scraper has the same contour shape as the front end of the camera lens rod. The applicable contour of the front end of the camera lens rod is an axisymmetric structure; the coke cleaning scraper can rotate together with the outer sleeve movable section;

[0011] It further includes a remote control system which is connected to and controls the track power box and the motor.

[0012] Preferably, the front end profile of the camera lens rod is hemispherical.

[0013] Preferably, one or more defocusing rods are provided on the hemispherical surface at the front end of the camera lens rod, and the length of the defocusing rod is less than the outermost edge of the movable section of the outer sleeve.

[0014] Preferably, the number of the defocusing rods is 4. According to the positions, they are divided into front defocusing rods and rear defocusing rods, and are arranged in two groups at the axially symmetric positions on both sides of the defocusing scraping strip. Among them, the rear defocusing rods are arranged at the position close to the flat head end edge of the movable section of the outer sleeve, and the front defocusing rods are arranged at the position close to the top of the hemispherical surface of the camera lens rod.

[0015] Preferably, it further includes a purging air passage which includes a camera lens rod purging air inlet, an endoscope tube purging air inlet, an outer sleeve purging air inlet and a purging air outlet; a compressed air pipeline is provided in the sensor box and is respectively connected to the camera lens rod and the endoscope tube; the camera lens rod purging air inlet and the endoscope tube purging air inlet are both arranged on the sensor box and are connected to the compressed air pipeline; the outer sleeve purging air inlet is arranged on the fixed section of the outer sleeve; the purging air outlet is the light inlet hole on the hemispherical surface at the front end of the camera lens rod.

[0016] Preferably, the track box is perpendicular to the base. One end of the track box is fixed to the base, and the other end is connected to the track power box which is used to provide telescopic power.

[0017] Preferably, there are 2 groups of the motors which are respectively arranged on the upper and lower or left and right sides of the movable section of the outer sleeve. The annular gear is connected and fixed to the movable section of the outer sleeve through two fixed beams, and the fixed beams are connected to the tracks in the track box and can move along the tracks.

[0018] Preferably, a position sensor is arranged on one of the two fixed beams for identifying the reset state and the maximum rotation angle state of the rotation angle of the outer sleeve and sending out position signals.

[0019] Preferably, the diameter of the connecting part of the movable section of the outer sleeve is smaller than that of the fixed section of the outer sleeve, and it can extend into the inside of the fixed section of the outer sleeve for a certain length; the sealing structure adopts double sealing of labyrinth seal and stuffing seal, and an annular ball bearing or other bearings beneficial to reducing the rotational friction are arranged on the outside of the double sealing, and a movable buckle for restricting the movable section of the outer sleeve is arranged at the outermost edge of the sealing structure.

[0020] Preferably, the remote control system is a PLC or a DCS.

[0021] The beneficial effects of the present utility model are as follows:

[0022] The on-line automatic defocusing device of the present utility model can further reduce the coking speed and cooling effect at the front end of the lens rod by sleeving an outer sleeve on the lens rod of a conventional camera and introducing purging gas into the interlayer; a semi-circular defocusing scraping strip for automatic defocusing is arranged at the front end of the outer sleeve, which can continuously defocus on-line without withdrawing the camera and remove the coke blocks around the front end of the lens rod and the light inlet hole; 4 fixed defocusing small columns are arranged on the hemispherical surface at the front end of the inner lens rod, which can be used to remove the coke blocks on the edge of the front end of the outer sleeve and the defocusing scraping strip, avoiding the influence on the camera vision due to the coking of the outer sleeve; the rotation drive of the outer sleeve is driven by a stepping motor or other power such as hydraulic pressure or compressed air to rotate at a certain angle, and the drive mechanism is located outside the furnace wall and will not be affected by the high-temperature environment in the furnace and can work for a long time. At the same time, the defocusing process of the present utility model is easy to realize automatic operation, can be set for regular automatic cleaning and manual operation by accessing the remote centralized control system, and because of the on-line defocusing function, the continuous and stable operation of the camera is guaranteed, the maintenance workload is reduced, and at the same time, the adaptability to the harsh high-concentration dust environment is increased, broadening the application scenario of the camera. Description of the Drawings

[0023] Figure 1 It is a schematic structural diagram of the on-line automatic defocusing device for the high-temperature camera in the furnace;

[0024] Figure 2 It is a schematic cross-sectional view of the outer sleeve;

[0025] Figure 3 It is a schematic diagram of the maximum rotation angle state of the outer sleeve;

[0026] Figure 4 It is a schematic structural diagram of the front end of the outer sleeve and the camera lens rod;

[0027] Figure 5 It is a schematic diagram of the sealing structure of the outer sleeve;

[0028] Figure 6 It is a flow chart of the defocusing process;

[0029] In the figure: 1, sensor box; 2, purge air inlet for camera mirror rod; 3, purge air inlet for endoscope tube; 4, fixed section of endoscope tube; 5, detachable section of endoscope tube; 6, front end of endoscope tube; 7, light inlet hole; 8, fixing bracket; 9, inner wall of furnace body; 10, embedded part; 11, base; 12, track power box; 13, track box; 100, fixed section of outer sleeve; 101, movable section of outer sleeve; 102, sealing structure; 103, ring gear; 104, motor; 105, driving gear; 106, purge air inlet for outer sleeve; 107, rear coke cleaning rod; 108, front coke cleaning rod; 109, coke cleaning scraper; 110, fixing beam; 111, position sensor; 201, annular ball bearing; 202, packing seal; 203, labyrinth seal; 204, movable buckle. Detailed implementation mode

[0030] The following further describes the present utility model in detail with reference to the accompanying drawings and specific embodiments.

[0031] Embodiment 1

[0032] An on-line automatic coke cleaning device for a high-temperature camera in a furnace, as Figure 1 shown, includes a furnace body. A hole is opened on the inner wall 9 of the furnace body. An embedded part 10 is arranged in the hole. One end of the embedded part 10 exposed from the inner wall 9 of the furnace body is provided with a base 11. The base 11 is sequentially connected to a track box 13 and a track power box 12. Among them, the track box 13 is perpendicular to the base 11. One end of the track box 13 is fixed on the base 11, and the other end is connected to the track power box 12. The track power box 12 is used to provide telescopic power. A track for carrying the telescopic movement of the camera mirror rod is arranged in the track box 13. A high-temperature resistant camera is arranged in parallel below the track box 13. The high-temperature resistant camera is connected to the track in the track box 13 through a fixing bracket 8. The track in the track box 13 and the matching track power box 12 are mainly used for the purposes such as the commissioning, withdrawal of the high-temperature resistant camera, and the automatic protective withdrawal in case of accidents.

[0033] As Figure 1As shown, the high-temperature resistant camera (this camera is a conventional device) includes a telescopable camera lens rod (not shown in the figure) and an associated sensor box 1. A camera sensor is provided inside the sensor box 1. One end of the camera lens rod is connected to the camera sensor. An inner lens barrel is provided around the outer circumference of the rod body of the camera lens rod. A rotatable outer sleeve is sleeved outside the barrel body of the inner lens barrel. The inner lens barrel is mainly used to protect the front end of the camera lens rod (the position where the front end 6 of the inner lens barrel is located) and the light inlet hole 7. For the convenience of manufacturing and installation, it is divided into two parts: an inner lens barrel fixed section 4 and an inner lens barrel detachable section 5. The two parts are connected by a flange. The outer sleeve is sleeved outside the inner lens barrel and has a diameter larger than that of the inner lens barrel. For the convenience of manufacturing and installation, it is also divided into two parts: an outer sleeve fixed section 100 and an outer sleeve movable section 101.

[0034] As Figure 1 shown, the inner lens barrel includes an inner lens barrel fixed section 4, an inner lens barrel detachable section 5, and an inner lens barrel front end 6 that are sequentially connected to the sensor box 1. The inner lens barrel fixed section 4 is connected to the fixed bracket 8. The outer sleeve is sleeved outside the inner lens barrel detachable section 5.

[0035] As Figure 1 shown, the outer sleeve includes an outer sleeve fixed section 100 and an outer sleeve movable section 101. The outer sleeve fixed section 100 is fixed to the inner lens barrel detachable section 5. There is a movable buckle 204 ( Figure 5 ) between the outer sleeve movable section 101 and the outer sleeve fixed section 100. The lateral movement of the outer sleeve movable section 101 is restricted by the movable buckle 204. A raised sealing structure 102 is provided at the joint of the outer sleeve movable section 101 and the outer sleeve fixed section 100. A ring gear 103 is provided around the outer circumference of the outer sleeve movable section 101. The ring gear 103 is connected to the motor 104 through a transmission gear 105. The outer sleeve movable section 101 can achieve a rotational movement under the drive of the ring gear 103 driven by the motor 104, and the rotation center is the center line of the camera lens rod.

[0036] As Figure 1 shown, the end of the outer sleeve movable section 101 is a flat head structure and is flush with the straight pipe end of the inner lens barrel detachable section 5. A strip-shaped defocusing scraping strip 109 is provided at the end of the outer sleeve movable section 101. The defocusing scraping strip 109 has the same contour shape as the front end of the camera lens rod. The applicable front end contour of the camera lens rod is an axisymmetric structure. In this embodiment, the front end contour structure of the camera lens rod is hemispherical. The defocusing scraping strip 109 can rotate together with the outer sleeve movable section 101. During the movement, it can scrape off the coke blocks surrounding the inner lens barrel front end 6 and the light inlet hole 7, achieving the purpose of on-line defocusing.

[0037] As Figures 2 - 4As shown, four focus clearing rods are arranged on the hemispherical surface at the front end of the camera mirror rod. The focus clearing rods cannot extend beyond the outermost edge of the outer sleeve movable section 101. They are divided into front focus clearing rods 108 and rear focus clearing rods 107 according to their positions. They are arranged in two groups at the axisymmetric positions on both sides of the focus clearing scraper 109. For ease of operation, the position of the focus clearing rods should be close to the reset state ( Figure 2 ) of the focus clearing scraper 109. The rear focus clearing small rod 107 is arranged near the edge of the flat end of the outer sleeve movable section 101, and is mainly used to clear the coke blocks at the edge when the outer sleeve moves; the front focus clearing small rod 108 is arranged near the top of the hemispherical surface of the camera lens rod or the furnace side, and is closer to the furnace side than the light inlet 7 in the horizontal direction, so as to clear the continuous coke blocks on the front end of the focus clearing scraper 109 when the outer sleeve moves, so as to prevent the field of view of the light inlet 7 from being blocked.

[0038] like Figure 1 As shown, the online automatic defocusing device also includes a purge air passage, which includes a camera mirror rod purge air inlet 2, an inner lens barrel purge air inlet 3, an outer sleeve purge air inlet 106 and a purge air outlet, as well as a compressed air pipeline arranged in the sensor box 1 (respectively connected to the camera mirror rod and the inner lens barrel, which belongs to the conventional technology of the endoscopic camera) and an external compressed air system or fan (arranged on the outside of the furnace body) for providing compressed air; the camera mirror rod purge air inlet 2 and the inner lens barrel purge air inlet 3 are both arranged on the sensor box 1, and are connected to the compressed air pipeline in the sensor box 1; the outer sleeve purge air inlet 106 is arranged on the outer sleeve fixed section 100; the purge air outlet is the light inlet 7 on the hemispherical surface of the front end of the camera mirror rod. The purge air flows between the annular gap between the inner lens barrel and the camera lens rod, and flows out in a concentrated manner at the front circular light inlet 7 to form a high-speed jet, which prevents and slows down the accumulation of dust and coking at the light inlet 7. Since the purge air is compressed air at room temperature, it also cools the front end of the camera lens rod to prevent overheating. There is an annular gap between the outer sleeve and the inner lens barrel. The purge air enters from the outer sleeve purge air inlet 106 of the outer sleeve fixed section 100, flows along the outer sleeve in the annular gap, and flows out from the purge air outlet (i.e., light inlet 7) at the front end of the outer sleeve movable section 101, forming a circle of annular protective gas with cooling and dust removal functions. At the same time, the width of the defocusing scraper 109 should be smaller than the diameter of the camera lens rod light inlet 7 to prevent the light inlet 7 from being completely blocked during the defocusing process, so that the purge air cannot flow out smoothly, resulting in the scraped coke fragments taking the opportunity to enter the light inlet 7.

[0039] like Figure 1As shown in the figure, there are two sets of the motors 104, which are respectively arranged on the upper and lower sides or the left and right sides of the movable section 101 of the outer sleeve, and drive the transmission gear 105 to drive the annular gear 103 connecting the outer sleeve to make a rotational movement. The annular gear 103 is connected and fixed to the movable section 101 of the outer sleeve through two fixed beams 110, and the fixed beams 110 are connected to the tracks in the track box 13 and can move along the tracks. The motor 104 is not limited to a stepper motor, and can also be other forms such as hydraulic pressure and compressed air power, as long as it can achieve the function of providing rotational power.

[0040] As Figure 2 , 3 shown, a position sensor 111 is arranged on one of the two fixed beams 110, which is used to identify the reset state and the maximum rotation angle state of the rotation angle of the outer sleeve and send out position signals. The reset state ( Figure 2 ) is the initial state after installation and debugging, that is, the state when defocusing has not started, and the maximum rotation angle state ( Figure 3 ) is the state when the outer sleeve rotates to the maximum angle during each defocusing. In the maximum rotation angle state, the defocusing scraper 109 has to move from one side of the light inlet hole 7 to the other side to completely scrape the coke blocks around the light inlet hole 7. At the same time, in the maximum rotation angle state, the defocusing scraper 109 will not touch the four defocusing small rods.

[0041] As Figure 5 shown, the connection part between the fixed section 100 of the outer sleeve and the movable section 101 of the outer sleeve adopts a sleeve structure. The diameter of the connection part of the movable section 101 of the outer sleeve is smaller than that of the fixed section 100 of the outer sleeve and can extend into the fixed section 100 of the outer sleeve by a certain length; the sealing structure 102 adopts a double seal of a labyrinth seal 203 and a stuffing seal 202. At the same time, an annular ball bearing 201 or other bearings beneficial to reducing rotational friction are arranged outside the double seal, and a movable buckle 204 for restricting the movable section 101 of the outer sleeve is arranged at the outermost edge of the sealing structure 102.

[0042] The on-line automatic defocusing device further includes a remote control system. The remote control system is connected to and controls the track power box 12 and the motor 104, and at the same time receives the position signals transmitted by the position sensor 111. The defocusing process can flexibly set the remote control system to the PLC mode or can be connected to a distributed control system (DCS). And a temperature sensor is arranged on the high-temperature camera, and a pressure sensor is arranged on the externally connected compressed air system or the fan, and both can transmit signals to the remote control system. When the instrument overheats or the compressed air pressure is insufficient, the remote control system will control the high-temperature camera to retract for self-protection.

[0043] Based on a complete defocusing process of the on-line automatic defocusing device of the above-mentioned high-temperature camera in the furnace, as Figure 6 shown, the specific steps are as follows:

[0044] Send a defocusing command, and detect whether the outer sleeve position sensor 111 is in the reset state. If it is, rotate the motor 104 forward to start driving the outer sleeve to rotate, drive the defocusing device to defocus. When the position sensor 111 reaches the maximum rotation angle position state, send a signal to change the rotation direction of the motor 104, rotate the outer sleeve in the reverse direction, and defocus in the reverse direction once. When it returns to the reset state, a complete defocusing process is completed. The defocusing process can be set to execute once at a fixed time interval, or can be defocused flexibly according to needs manually.

[0045] The embodiments described above are only a part of the embodiments of the present invention, rather than all embodiments. The detailed description of the embodiments of the present invention is not intended to limit the scope of the present invention claimed, but only represents the selected embodiments of the present invention. The protection scope of the present invention shall be subject to the scope required by the claims. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

Claims

1. An online automatic defocusing device for a high-temperature camera in a furnace, comprising a furnace body, characterized in that: A hole is provided on the inner wall of the furnace body, an embedded part is provided in the hole, a base is provided at one end of the embedded part exposed from the inner wall of the furnace body, and the base is sequentially connected to the track box and the track power box; a track for carrying the telescopic mirror rod of the camera is provided in the track box; a high-temperature resistant camera is provided in parallel below the track box, and the high-temperature resistant camera is connected to the track in the track box through a fixed bracket; The high temperature resistant camera comprises a freely retractable camera mirror rod and an associated sensor box, wherein a camera sensor is arranged in the sensor box; one end of the camera mirror rod is connected to the camera sensor, an inner lens barrel is arranged around the outer side of the rod body of the camera mirror rod, and a rotatable outer sleeve is sleeved on the outer side of the barrel body of the inner lens barrel; the inner lens barrel comprises an inner lens barrel fixed section, an inner lens barrel detachable section and an inner lens barrel front end which are sequentially connected to the sensor box, the inner lens barrel fixed section is connected to a fixed bracket; the outer sleeve is sleeved on the outer side of the inner lens barrel detachable section; the outer sleeve comprises an outer sleeve fixed section and an outer sleeve movable section, the outer sleeve fixed section is fixed to the inner lens barrel detachable section, a movable buckle is arranged between the outer sleeve movable section and the outer sleeve fixed section, and the outer sleeve fixed section is fixed to the inner lens barrel detachable section. The movable section of the sleeve is constrained by a movable buckle to prevent its lateral movement; a raised sealing structure is provided at the joint between the movable section of the outer sleeve and the fixed section of the outer sleeve; a ring gear is provided on the outer side of the movable section of the outer sleeve, and the ring gear is connected to the motor through a transmission gear. The movable section of the outer sleeve can realize rotational movement under the ring gear driven by the motor, and the center of rotation is the center line of the camera mirror rod; the end of the movable section of the outer sleeve is a flat-head structure, which is flush with the straight tube end of the detachable section of the inner lens barrel; a strip-shaped defocusing scraper is provided at the end of the movable section of the outer sleeve, and the defocusing scraper is consistent with the contour of the front end of the camera mirror rod, and the front end contour of the applicable camera mirror rod is an axisymmetric structure; the defocusing scraper can rotate with the movable section of the outer sleeve; Also included is a remote control system, which is connected to and controls the track power box and the motor.

2. The online automatic defocusing device for a high-temperature camera in a furnace according to claim 1, characterized in that: The front end profile of the camera mirror rod is hemispherical.

3. The online automatic defocusing device for a high-temperature camera in a furnace according to claim 2, characterized in that: One or more small focus clearing rods are arranged on the hemispherical surface at the front end of the camera mirror rod, and the length of the small focus clearing rods is smaller than the outermost edge of the movable section of the outer sleeve.

4. The online automatic defocusing device for a high-temperature camera in a furnace according to claim 3, characterized in that: There are four small focus clearing rods, which are divided into front focus clearing rods and rear focus clearing rods according to their positions, and are arranged in two groups at axially symmetrical positions on both sides of the focus clearing scraper strip, wherein the rear focus clearing rods are arranged near the edge of the flat head end of the movable section of the outer sleeve, and the front focus clearing rods are arranged near the top of the hemispherical surface of the camera mirror rod.

5. The online automatic focus clearing device for a high-temperature camera in a furnace according to claim 2, characterized in that: It also includes a purge air passage, which includes a camera mirror rod purge air inlet, an inner lens barrel purge air inlet, an outer sleeve purge air inlet and a purge air outlet; a compressed air pipeline is provided in the sensor box, which is respectively connected to the camera mirror rod and the inner lens barrel, and the camera mirror rod purge air inlet and the inner lens barrel purge air inlet are both arranged on the sensor box and connected to the compressed air pipeline; the outer sleeve purge air inlet is arranged on the outer sleeve fixed section; the purge air outlet is a light inlet on the hemispherical surface of the front end of the camera mirror rod.

6. The online automatic focus clearing device for a high-temperature camera in a furnace according to claim 1, characterized in that: The track box and the base are perpendicular to each other, one end of the track box is fixed on the base, and the other end is connected to a track power box, and the track power box is used to provide telescopic power.

7. The online automatic defocusing device for a high-temperature camera in a furnace according to claim 1, characterized in that: The motor is provided with two groups, which are respectively arranged on the upper and lower sides or the left and right sides of the outer sleeve movable section. The ring gear is connected and fixed to the outer sleeve movable section through two fixed beams. The fixed beams are connected to the track in the track box and can move along the track.

8. The online automatic defocusing device for a high-temperature camera in a furnace according to claim 7, characterized in that: A position sensor is arranged on one of the two fixed beams for identifying the reset state and the maximum rotation angle state of the outer sleeve rotation angle and sending out a position signal.

9. The online automatic focus clearing device for a high-temperature camera in a furnace according to claim 1, characterized in that: The diameter of the connection part of the outer sleeve movable section is smaller than that of the outer sleeve fixed section, and can extend into a part of the inner part of the outer sleeve fixed section; the sealing structure adopts a labyrinth seal and a packing seal for double sealing, and an annular ball bearing or other bearings that are beneficial to reducing rotational friction are provided on the outer side of the double seal, and a movable buckle that constrains the outer sleeve movable section is provided on the outermost edge of the sealing structure.

10. The online automatic defocusing device for a high-temperature camera in a furnace according to claim 1, characterized in that: The remote control system is PLC or DCS.

Images