Device for automatically detecting thickness of accumulated ice on surface of unmanned aerial vehicle body

Abstract

The utility model belongs to the technical field of unmanned aerial vehicles, and particularly relates to an unmanned aerial vehicle body surface icing thickness automatic detection device which comprises an unmanned aerial vehicle body, an installation shell is fixedly installed on the upper portion of the unmanned aerial vehicle body, an image acquisition mechanism is arranged in the installation shell, and a deicing mechanism is arranged on the upper portion of the installation shell. A mounting groove is formed in the upper portion of a supporting arm of the unmanned aerial vehicle body, an ultrasonic sensor is fixedly mounted on the inner side wall of the mounting groove, and protective glass is fixedly mounted on the inner side wall of the upper portion of the mounting groove. According to the device for automatically detecting the thickness of the accumulated ice on the surface of the unmanned aerial vehicle body, the ultrasonic sensor is arranged, the ultrasonic sensor can detect the thickness rate of the accumulated ice by receiving different ultrasonic waves reflected on the surface of the accumulated ice and in the accumulated ice, and the protective glass is arranged to protect the sensor; the image acquisition mechanism is arranged to carry out image recording on the ice accumulation condition on the surface of the unmanned aerial vehicle body, and the deicing mechanism is arranged to eliminate too thick ice accumulation.

Description

Technical Field

[0001] The utility model relates to the technical field of unmanned aerial vehicles (UAVs), in particular to a device for automatically detecting ice thickness on the surface of a UAV body. Background Art

[0002] Drone ice accumulation refers to the phenomenon of ice accumulation on certain parts of the drone's fuselage. It is formed when supercooled water in the clouds or precipitation freezes after hitting the fuselage. Drone ice accumulation can pose a serious threat to the safe flight of the drone, affecting the drone's maneuverability and safety, and even causing the drone to crash.

[0003] When performing artificial rainmaking operations, drones often need to fly into clouds with abundant supercooled water, which greatly increases the probability of the drone encountering ice accumulation and also increases the safety risk of the drone. Therefore, it is necessary to design a device that can be mounted on the surface of the drone to automatically detect the thickness and rate of ice accumulation. When the ice accumulation reaches a certain thickness, it can transmit a real-time alarm to the operator of the drone. Utility Model Content

[0004] Based on the technical problems of the existing device for automatically detecting ice accumulation thickness and ice accumulation rate on the surface of a UAV body, the utility model proposes a device for automatically detecting ice accumulation thickness on the surface of a UAV body.

[0005] The utility model proposes a device for automatically detecting the thickness of ice accumulation on the surface of a drone body, comprising a drone body, a mounting shell fixedly mounted on the upper part of the drone body, an image acquisition mechanism provided inside the mounting shell, a de-icing mechanism provided on the upper part of the mounting shell, a mounting groove provided on the upper part of the support arm of the drone body, an ultrasonic sensor fixedly mounted on the inner side wall of the mounting groove, and a protective glass fixedly mounted on the upper inner side wall of the mounting groove.

[0006] Preferably, the image acquisition mechanism includes a fixed shaft, which is fixedly mounted on the inner bottom surface of the mounting shell, a fixed gear is fixedly connected to the middle arc surface of the fixed shaft, and a rotating disk is rotatably connected to the upper arc surface of the fixed shaft through a ball bearing, and a capture camera is fixedly mounted on the upper part of the rotating disk. Observation ports are respectively provided on the four side surfaces of the mounting shell, and an observation glass is fixedly mounted on the inner side wall of the observation port.

[0007] Through the above technical solution, a rotating disk is provided, and by rotating the rotating disk, the collection camera on the rotating disk can be rotated together, so that it can respectively collect images of the ice accumulation conditions on the surfaces of the four arms of the drone body, and transmit the images to the drone body operating table, so that the operator can clearly see the ice accumulation conditions on the surface of the drone body. An observation glass is provided to allow the collection camera to perform video collection without hindrance, and at the same time protect the collection camera in the installation shell.

[0008] Preferably, the upper surface of the rotating disk is rotatably connected to a rotating shaft through a ball bearing, the lower part of the rotating shaft passes through and extends out of the lower part of the rotating disk, a first motor is fixedly installed on the upper part of the rotating disk, the output end of the first motor is fixedly connected to the upper end of the rotating shaft through a coupling, and a rotating gear is fixedly connected to the arc surface of one end of the rotating shaft extending out of the lower part of the rotating disk, and the teeth of the rotating gear are engaged with the tooth grooves of the fixed gear.

[0009] Through the above technical solution, a first motor is set up, and starting the first motor can make the rotating shaft drive the rotating gear to rotate, and the rotating gear is engaged with the fixed gear. The rotation of the rotating gear drives the rotating disk to automatically rotate with the fixed shaft as the center.

[0010] Preferably, the de-icing mechanism includes a support shaft, which is fixedly mounted on the middle part of the rotating disk, the upper end of the support shaft passes through and extends above the mounting shell, and the arc surface of the support shaft is rotatably connected to the upper surface of the mounting shell through a ball bearing, the upper part of the support shaft extending from the upper part of the mounting shell is fixedly mounted with a support shell, the inner bottom surface of the support shell is fixedly mounted with a mounting plate, the opposing surfaces of the two mounting plates are slidably plugged with a first sliding shell, the inner bottom surface of the first sliding shell is fixedly mounted with a fixed plate, and the opposing surfaces of the two fixed plates are slidably plugged with a second sliding shell.

[0011] Through the above technical solution, a support shaft is set, and the rotation of the rotating disk can drive the support shaft to rotate, and drive the support shell to rotate, so that the de-icing mechanism can rotate to de-ice the ice accumulated on the four arms of the drone body.

[0012] Preferably, a support plate is fixedly mounted on the inner side wall of the support shell, one side surface of the support plate is rotatably connected with a screw through a ball bearing, and one side of the support plate is fixedly mounted with a second motor, the output end of the second motor is fixedly connected to one end of the screw through a coupling, and the threaded surface of the screw is threadedly connected to one side surface of the first sliding shell.

[0013] Through the above technical solution, a second motor is provided, and starting the second motor can drive the screw to rotate, so that the first sliding shell can slide back and forth in the supporting shell along the axis of the screw.

[0014] Preferably, sliding grooves are respectively provided on both sides of the first sliding shell, and mounting shafts are fixedly installed on the upper and lower opposite surfaces of the sliding grooves, and the arc surface of the mounting shaft is rotatably connected to the adjusting gear through a ball bearing, and first straight racks are respectively fixedly installed on the inner walls of both sides of the supporting shell, and second straight racks are respectively fixedly installed on the outer surfaces of both sides of the second sliding shell, and the tooth grooves of the first straight rack and the tooth grooves of the second straight rack are both engaged with the gear teeth of the adjusting gear.

[0015] Through the above technical solution, an adjusting gear, a first spur rack and a second spur rack are provided. When the first sliding shell slides inward and outward, the adjusting gear is driven to slide. The adjusting gear is meshed with the first spur rack and the first spur rack is fixed to the inner wall of the supporting shell, so that the adjusting gear rotates around the mounting axis. The adjusting gear is meshed with the second spur rack and the second spur rack is fixed to the outer surface of the second sliding shell. The rotation of the adjusting gear causes the second spur rack to drive the second sliding shell to slide, so that the second sliding shell can be driven to slide together by the inward and outward sliding of the first sliding shell.

[0016] Preferably, a fixing ring is fixedly mounted on the front end of the second sliding shell, a heating wire is fixedly mounted on the inner side wall of the fixing ring, and an air blowing fan is fixedly mounted on the lower part of the fixing ring.

[0017] Through the above technical solution, a heating wire and an air blowing fan are set up, and the heating wire is started. The air blowing fan can transport the hot air heated by the heating wire to the surface of the drone body arm, thereby accelerating the melting of accumulated ice.

[0018] The beneficial effects of the present invention are:

[0019] 1. An ultrasonic sensor is provided, which can detect the thickness and rate of ice accumulation on the surface of the UAV's support arm by receiving different ultrasonic waves reflected on the surface and inside of the ice accumulation. A protective glass is provided to protect the sensor without affecting the propagation of ultrasonic waves. An image acquisition mechanism is provided to record the ice accumulation on the surface of the UAV's body. A de-icing mechanism is provided to remove excessive ice on the surface of the UAV's body.

[0020] 2. By setting a first motor and starting the first motor, the rotating shaft can drive the rotating gear to rotate, and the rotating gear is engaged with the fixed gear. The rotation of the rotating gear drives the rotating disk to automatically rotate with the fixed shaft as the center. A rotating disk is set. By rotating the rotating disk, the collection camera on the rotating disk can be rotated together, so that it can respectively collect images of the ice accumulation conditions on the surfaces of the four arms of the drone body, and transmit the images to the drone body operating table, so that the operator can clearly see the ice accumulation conditions on the surface of the drone body. An observation glass is provided to allow the collection camera to perform video collection without hindrance, and at the same time protect the collection camera in the installation shell.

[0021] 3. By setting a second motor, starting the second motor can drive the screw to rotate, so that the first sliding shell can slide back and forth in the supporting shell along the axis of the screw, and setting an adjusting gear, a first spur rack and a second spur rack. When the first sliding shell slides inward and outward, the adjusting gear is driven to slide, and the adjusting gear is engaged with the first spur rack and the first spur rack is fixed to the inner wall of the supporting shell, so that the adjusting gear rotates around the mounting axis, and the adjusting gear is engaged with the second spur rack and the second spur rack is fixed to the outer surface of the second sliding shell. The rotation of the adjusting gear causes the second spur rack to drive the second sliding shell to slide, so that the second sliding shell can be driven to slide together by the inward and outward sliding of the first sliding shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of a device for automatically detecting ice thickness on the surface of a drone body proposed in the present invention;

[0023] Figure 2 This is a three-dimensional diagram of the mounting shell structure of a device for automatically detecting ice accumulation thickness on the surface of a drone body proposed in the utility model;

[0024] Figure 3 This is a three-dimensional diagram of the rotating gear structure of a device for automatically detecting ice accumulation thickness on the surface of a drone body proposed in the utility model;

[0025] Figure 4 This is an exploded perspective view of the support shell of a device for automatically detecting ice accumulation thickness on the surface of a UAV body proposed in the utility model;

[0026] Figure 5 This is a cross-sectional view of the support shell of a device for automatically detecting ice accumulation thickness on the surface of a UAV body proposed in the utility model;

[0027] Figure 6 This is a three-dimensional diagram of the first sliding shell structure of a device for automatically detecting ice accumulation thickness on the surface of a drone body proposed by the utility model.

[0028] In the figure: 1. UAV body; 2. Mounting shell; 3. Mounting slot; 4. Ultrasonic sensor; 5. Protective glass; 6. Fixed shaft; 7. Fixed gear; 8. Rotating disk; 9. Collection camera; 10. Observation port; 11. Observation glass; 12. Rotating shaft; 13. First motor; 14. Rotating gear; 15. Support shaft; 16. Support shell; 17. Mounting plate; 18. First sliding shell; 19. Fixed plate; 20. Second sliding shell; 21. Support plate; 22. Screw; 23. Second motor; 24. Sliding slot; 25. Mounting shaft; 26. Adjusting gear; 27. First spur rack; 28. Second spur rack; 29. Fixed ring; 30. Heating wire; 31. Blowing fan. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0030] Reference Figures 1-6 A device for automatically detecting ice accumulation thickness on the surface of a drone body includes a drone body 1, a mounting shell 2 is fixedly installed on the upper part of the drone body 1, an image acquisition mechanism is provided inside the mounting shell 2, a de-icing mechanism is provided on the upper part of the mounting shell 2, a mounting groove 3 is opened on the upper part of the support arm of the drone body 1, an ultrasonic sensor 4 is fixedly installed on the inner side wall of the mounting groove 3, and a protective glass 5 is fixedly installed on the upper inner side wall of the mounting groove 3.

[0031] The image acquisition mechanism includes a fixed shaft 6, which is fixedly mounted on the inner bottom surface of the mounting shell 2. The middle arc surface of the fixed shaft 6 is fixedly connected to a fixed gear 7. The upper arc surface of the fixed shaft 6 is rotatably connected to a rotating disk 8 through a ball bearing. A collection camera 9 is fixedly mounted on the upper part of the rotating disk 8. Observation ports 10 are respectively provided on the four side surfaces of the mounting shell 2, and an observation glass 11 is fixedly mounted on the inner wall of the observation port 10.

[0032] By setting a rotating disk 8, the collection camera 9 on the rotating disk 8 can be rotated together by rotating the rotating disk 8, so that it can respectively collect images of the ice accumulation conditions on the surfaces of the four arms of the drone body 1, and transmit the images to the drone body operating table, so that the operator can clearly see the ice accumulation conditions on the surface of the drone body 1. An observation glass 11 is provided to allow the collection camera 9 to perform video collection without hindrance, while protecting the collection camera 9 in the mounting shell 2.

[0033] In order to enable the rotating disk 8 to rotate automatically, a rotating shaft 12 is rotatably connected to the upper surface of the rotating disk 8 through a ball bearing. The lower part of the rotating shaft 12 passes through and extends out of the lower part of the rotating disk 8. A first motor 13 is fixedly installed on the upper part of the rotating disk 8. The output end of the first motor 13 is fixedly connected to the upper end of the rotating shaft 12 through a coupling. A rotating gear 14 is fixedly connected to the arc surface of one end of the rotating shaft 12 extending out of the lower part of the rotating disk 8. The teeth of the rotating gear 14 are engaged with the tooth grooves of the fixed gear 7.

[0034] By providing the first motor 13 and starting the first motor 13 , the rotating shaft can drive the rotating gear 14 to rotate. The rotating gear 14 is engaged with the fixed gear 7 . The rotation of the rotating gear 14 drives the rotating disk 8 to automatically rotate around the fixed shaft 6 .

[0035] In order to enable the de-icing mechanism to rotate, the de-icing mechanism includes a support shaft 15, which is fixedly mounted on the middle part of the rotating disk 8. The upper end of the support shaft 15 passes through and extends above the mounting shell 2, and the arc surface of the support shaft 15 is rotatably connected to the upper surface of the mounting shell 2 through a ball bearing. The upper part of the support shaft 15 extending from the upper part of the mounting shell 2 is fixedly mounted with a support shell 16, and the inner bottom surface of the support shell 16 is fixedly mounted with a mounting plate 17. The opposite surfaces of the two mounting plates 17 are slidably plugged with a first sliding shell 18, and the inner bottom surface of the first sliding shell 18 is fixedly mounted with a fixed plate 19. The opposite surfaces of the two fixed plates 19 are slidably plugged with a second sliding shell 20.

[0036] By providing the support shaft 15 , the rotation of the rotating disk 8 can drive the support shaft 15 to rotate, and drive the support shell 16 to rotate, so that the de-icing mechanism can rotate to de-ice the ice accumulated on the four arms of the drone body 1 .

[0037] In order to enable the first sliding shell 18 to slide in the supporting shell 16, a support plate 21 is fixedly installed on the inner side wall of the supporting shell 16, and a screw 22 is rotatably connected to one side surface of the support plate 21 through a ball bearing. A second motor 23 is fixedly installed on one side of the support plate 21, and the output end of the second motor 23 is fixedly connected to one end of the screw 22 through a coupling. The threaded surface of the screw 22 is threadedly connected to the one side surface of the first sliding shell 18.

[0038] By providing the second motor 23 , starting the second motor 23 can drive the screw 22 to rotate, so that the first sliding shell 18 can slide back and forth along the axis of the screw 22 in the supporting shell 16 .

[0039] In order to enable the sliding of the first sliding shell 18 to drive the second sliding shell 20 to slide together, sliding grooves 24 are respectively opened on both sides of the first sliding shell 18, and the upper and lower opposite surfaces of the sliding grooves 24 are fixedly installed with mounting shafts 25. The arc surface of the mounting shaft 25 is rotatably connected to the adjusting gear 26 through a ball bearing. The inner walls on both sides of the support shell 16 are respectively fixedly installed with first straight racks 27, and the outer surfaces on both sides of the second sliding shell 20 are respectively fixedly installed with second straight racks 28. The tooth grooves of the first straight rack 27 and the tooth grooves of the second straight rack 28 are both engaged with the gear teeth of the adjusting gear 26.

[0040] By providing an adjusting gear 26, a first spur rack 27 and a second spur rack 28, when the first sliding shell 18 slides inward and outward, the adjusting gear 26 is driven to slide, and the adjusting gear 26 is meshed with the first spur rack 27 and the first spur rack 27 is fixed to the inner wall of the supporting shell 16, so that the adjusting gear 26 rotates around the mounting shaft 25, and the adjusting gear 26 is meshed with the second spur rack 28 and the second spur rack 28 is fixed to the outer surface of the second sliding shell 20. The rotation of the adjusting gear 26 causes the second spur rack 28 to drive the second sliding shell 20 to slide, so that the second sliding shell 20 can be driven to slide together by the inward and outward sliding of the first sliding shell 18.

[0041] In order to de-ice the surface of the arm of the drone body 1, a fixing ring 29 is fixedly installed at the front end of the second sliding shell 20, a heating wire 30 is fixedly installed on the inner side wall of the fixing ring 29, and an air blowing fan 31 is fixedly installed at the lower part of the fixing ring 29.

[0042] By providing the heating wire 30 and the blowing fan 31 and starting the heating wire 30 , the blowing fan 31 can transport the hot air heated by the heating wire 30 to the surface of the arm of the drone body 1 , thereby accelerating the melting of the accumulated ice.

[0043] Working principle: First, start the ultrasonic sensor 4, and detect the ice accumulation thickness and ice accumulation rate on the surface of the arm of the drone body 1 by receiving different ultrasonic waves reflected on the surface and inside of the ice accumulation. When the ice accumulation thickness on the surface of the drone body 1 increases rapidly, starting the first motor 13 can make the rotating shaft drive the rotating gear 14 to rotate, and the rotating gear 14 is engaged with the fixed gear 7. The rotation of the rotating gear 14 drives the rotating disk 8 to automatically rotate with the fixed shaft 6 as the center of the circle. The rotating disk 8 is set. By rotating the rotating disk 8, the collection camera 9 on the rotating disk 8 can be rotated together, so that it can respectively collect images of the ice accumulation conditions on the surfaces of the four arms of the drone body 1, and transmit the images to the drone body operating console, so that the operator can clearly see the ice accumulation conditions on the surface of the drone body 1. When it is found that the ice accumulation thickness is too thick, start the first motor 13 to make the rotating disk 8 drive the support shaft 15 to rotate, drive the support shell 16 to rotate, and make the support shell 16 point to the arm that needs to be de-iced, and then start the second motor 23 to drive the screw 22 to rotate, so that the first sliding shell 18 can slide forward and backward along the axis of the screw 22 in the support shell 16, and is provided with an adjusting gear 26, a first straight rack 27 and a second straight rack 28. When the first sliding shell 18 slides inward and outward, the adjusting gear 26 is driven to slide, and the adjusting gear 26 is meshed with the first straight rack 27 and the first straight rack 27 is fixed to the inner wall of the support shell 16, so that the adjusting gear 26 rotates around the mounting shaft 25, and the adjusting gear 26 is meshed with the second straight rack 28 and the second straight rack 28 is fixed to the outer surface of the second sliding shell 20. The rotation of 26 causes the second spur rack 28 to drive the second sliding shell 20 to slide, so that the second sliding shell 20 can be driven to slide together by the inward and outward sliding of the first sliding shell 18. The sliding of the first sliding shell 18 and the second sliding shell 20 causes the heating wire 30 and the blowing fan 31 at the front end of the second sliding shell 20 to move to above the arm of the drone body 1 that needs to be de-iced. The heating wire 30 is started, and the blowing fan 31 can transport the hot air heated by the heating wire 30 to the surface of the arm of the drone body 1, thereby accelerating the melting of accumulated ice.

[0044] The above are only preferred specific implementation methods of the present invention, but the protection scope of the present invention is not limited to them. Any technician familiar with the technical field can make equivalent replacements or changes based on the technical solution and utility model concept of the present invention within the technical scope disclosed by the present invention, and they should be covered by the protection scope of the present invention.

Claims

1. A device for automatically detecting ice thickness on the surface of a drone body, comprising a drone body (1), characterized in that: A mounting shell (2) is fixedly mounted on the upper portion of the drone body (1), an image acquisition mechanism is provided inside the mounting shell (2), a de-icing mechanism is provided on the upper portion of the mounting shell (2), a mounting slot (3) is provided on the upper portion of the support arm of the drone body (1), an ultrasonic sensor (4) is fixedly mounted on the inner side wall of the mounting slot (3), and a protective glass (5) is fixedly mounted on the upper inner side wall of the mounting slot (3); The image acquisition mechanism realizes the action of recording images of ice accumulation on the surface of the drone body (1); The de-icing mechanism realizes the removal of excessively thick ice accumulation on the surface of the drone body (1).

2. The device for automatically detecting ice thickness on the surface of a drone body according to claim 1, characterized in that: The image acquisition mechanism comprises a fixed shaft (6), the fixed shaft (6) being fixedly mounted on the inner bottom surface of the mounting shell (2), a fixed gear (7) being fixedly connected to the middle arc surface of the fixed shaft (6), a rotating disk (8) being rotatably connected to the upper arc surface of the fixed shaft (6) via a ball bearing, a collection camera (9) being fixedly mounted on the upper portion of the rotating disk (8), observation ports (10) being respectively provided on the four side surfaces of the mounting shell (2), and an observation glass (11) being fixedly mounted on the inner side wall of the observation port (10).

3. The device for automatically detecting ice thickness on the surface of a drone body according to claim 2, characterized in that: The upper surface of the rotating disk (8) is rotatably connected to a rotating shaft (12) via a ball bearing. The lower portion of the rotating shaft (12) penetrates and extends out of the lower portion of the rotating disk (8). A first motor (13) is fixedly mounted on the upper portion of the rotating disk (8). The output end of the first motor (13) is fixedly connected to the upper end of the rotating shaft (12) via a coupling. A rotating gear (14) is fixedly connected to the arc surface of one end of the rotating shaft (12) extending out of the lower portion of the rotating disk (8). The gear teeth of the rotating gear (14) mesh with the tooth grooves of the fixed gear (7).

4. The device for automatically detecting ice thickness on the surface of a drone body according to claim 3, characterized in that: The de-icing mechanism includes a support shaft (15), the support shaft (15) is fixedly mounted on the middle part of the rotating disk (8), the upper end of the support shaft (15) passes through and extends above the mounting shell (2), and the arc surface of the support shaft (15) is rotatably connected to the upper surface of the mounting shell (2) through a ball bearing, the upper part of the support shaft (15) extending from the upper part of the mounting shell (2) is fixedly mounted with a support shell (16), the inner bottom surface of the support shell (16) is fixedly mounted with a mounting plate (17), the opposite surfaces of the two mounting plates (17) are slidably plugged with a first sliding shell (18), the inner bottom surface of the first sliding shell (18) is fixedly mounted with a fixed plate (19), and the opposite surfaces of the two fixed plates (19) are slidably plugged with a second sliding shell (20).

5. The device for automatically detecting ice thickness on the surface of a drone body according to claim 4, characterized in that: A support plate (21) is fixedly mounted on the inner side wall of the support shell (16), a screw (22) is rotatably connected to one side surface of the support plate (21) via a ball bearing, a second motor (23) is fixedly mounted on one side of the support plate (21), an output end of the second motor (23) is fixedly connected to one end of the screw (22) via a coupling, and a threaded surface of the screw (22) is threadedly connected to a side surface of the first sliding shell (18).

6. The device for automatically detecting ice thickness on the surface of a drone body according to claim 5, characterized in that: Sliding grooves (24) are respectively provided on both sides of the first sliding shell (18), and mounting shafts (25) are fixedly installed on the upper and lower opposite surfaces of the sliding grooves (24), and the arc surface of the mounting shaft (25) is rotatably connected to the adjusting gear (26) through a ball bearing. First straight racks (27) are respectively fixedly installed on the inner walls of both sides of the support shell (16), and second straight racks (28) are respectively fixedly installed on the outer surfaces of both sides of the second sliding shell (20), and the tooth grooves of the first straight rack (27) and the tooth grooves of the second straight rack (28) are both engaged with the gear teeth of the adjusting gear (26).

7. The device for automatically detecting ice thickness on the surface of a drone body according to claim 6, characterized in that: A fixing ring (29) is fixedly mounted on the front end of the second sliding shell (20), a heating wire (30) is fixedly mounted on the inner side wall of the fixing ring (29), and an air blowing fan (31) is fixedly mounted on the lower part of the fixing ring (29).

Images