Orthopedic medical device C-arm

Abstract

The utility model provides a C-arm of an orthopedic medical device, including a C-arm bracket for structural support and rotation, an X-ray generator, located at one end of the C-arm bracket, responsible for generating X-rays; an image receiver, located at the other end of the C-arm bracket, used to capture X-rays that penetrate the human body and convert them into visible images; and a limit groove, used for limiting the structure, wherein the limit groove is arranged inside the C-arm bracket. The utility model can be connected to an external device through the connection seat by arranging a C-arm bracket, an X-ray generator, an image receiver, a limit groove, a moving structure, a connecting seat and an angle adjustment structure. By starting the angle adjustment structure, the angle adjustment structure drives the C-arm bracket to rotate, and the moving structure limits the C-arm bracket. When adjusted to a suitable position, the X-ray generator generates X-rays, and the generated X-rays penetrate the human body, and the image receiver captures the X-rays that penetrate the human body and converts them into visible images.

Description

Technical Field

[0001] The utility model relates to the technical field of orthopedic interventional radiological equipment, in particular to a C-shaped arm of orthopedic medical equipment. Background Art

[0002] The C-arm in orthopedic medical equipment, also known as C-arm or C-arm X-ray machine, is a medical device with a C-shaped frame. It consists of a tube that generates X-rays, an image intensifier that collects images, a CCD camera, and an image processing workstation. The main application areas of the C-arm include angiography and photography in various surgeries, especially in orthopedic surgery.

[0003] In orthopedic surgery, the C-arm can be used for bone setting, repositioning, and nailing. It is lightweight and can be easily moved to any location in the ward and operating room, providing doctors with timely fluoroscopy services, thereby helping doctors to position and operate more accurately. In addition, the C-arm also has high-quality imaging capabilities, which can provide clear images, allowing doctors to better observe and analyze the patient's condition.

[0004] Specifically, C-arms can be divided into different types, such as small C, medium C and large C. Small C is mainly used for surgical operations in orthopedics, surgery and other fields, such as bone setting, reduction, nailing, as well as removing foreign bodies from the body, cardiac catheterization, pacemaker implantation, etc. Medium C has more DSA-related functions and can be used in neurosurgery angiography, gastrointestinal interventional surgery, minimally invasive interventional surgery for pain and other fields. Large C, that is, DSA vascular machine, is mainly used for the diagnosis and treatment of systemic vascular diseases. It is a fixed device with high power.

[0005] When using a C-arm, medical staff need to follow the correct operating steps and pay attention to cleaning and disinfection precautions to ensure the normal operation of the equipment and the safety of patients. At the same time, since the X-rays generated by the C-arm are harmful to the human body, medical staff should pay attention to protection when using it.

[0006] In general, the orthopedic medical device C-arm is an important tool in modern medical technology. Its application has greatly improved the accuracy and safety of surgery and provided doctors with more convenient operation methods and clearer imaging effects.

[0007] In the existing technology, during long-term use, the C-arm of orthopedic medical equipment needs to be flexibly moved and positioned, so stability is taken into consideration during design to ensure that it can maintain balance at various angles and positions and reduce the risk of tipping. However, in actual operation, the external connection of the C-arm is at one side of the bottom, which can easily cause the center of gravity to shift and affect stability. At the same time, in long-term use, it may be worn due to frequent movement, rotation and load-bearing. However, it is difficult to disassemble the entire device, making it inconvenient to inspect and replace the structure. Utility Model Content

[0008] In view of the shortcomings of the prior art, the purpose of the utility model is to provide a C-arm for orthopedic medical equipment, which can provide a central support to improve the stability of the C-arm and facilitate the replacement and maintenance of the surface components of the C-arm, so as to solve the problems of the existing C-arm of orthopedic medical equipment having a center of gravity offset and inconvenient maintenance and replacement.

[0009] In order to achieve the above-mentioned purpose, the utility model is realized through the following technical solutions: an orthopedic medical device C-shaped arm, comprising a C-shaped arm bracket for structural support rotation,

[0010] The X-ray generator, located at one end of the C-arm support, is responsible for generating X-rays;

[0011] The image receiver is located at the other end of the C-arm support and is used to capture X-rays that have penetrated the human body and convert them into visible images;

[0012] A limiting groove is used for limiting the structure, and the limiting groove is opened inside the C-shaped arm bracket;

[0013] A moving structure, used to move on the surface of the C-shaped arm support, the surface of the moving structure being used in cooperation with the interior of the limiting groove;

[0014] A connecting seat, used for mounting and supporting the C-shaped arm bracket, one side of the connecting seat is fixedly connected to the surface of the mobile structure;

[0015] The angle adjustment structure is used to adjust the angle of the C-arm support. The angle adjustment structure is arranged inside the mobile structure and is used in conjunction with the surface of the C-arm support.

[0016] Furthermore, the movable structure includes a first movable seat for connection, the first movable seat is located at the inner ring of the C-shaped arm bracket, the four corners of the first movable seat are movably connected with first movable wheels, the surface of the first movable wheel is in contact and cooperate with the inner ring of the C-shaped arm bracket, the outer ring of the C-shaped arm bracket is provided with a second movable seat, the four corners of the second movable seat are movably connected with second movable wheels, the surface of the second movable wheel is in contact and cooperate with the outer ring of the C-shaped arm bracket, the top and bottom of the first movable seat are provided with detachable connecting parts, one side of the connecting part passes through the C-shaped arm bracket and is fixedly connected to the surface of the second movable seat, the other side of the second movable seat is fixedly connected to the surface of the connecting seat, the angle adjustment structure is located on the other side of the second movable seat, and one end of the angle adjustment structure passes through the second movable seat and is used in cooperation with the surface of the C-arm bracket.

[0017] Furthermore, the angle adjustment structure includes a stepper motor for power output, the output end of the stepper motor is fixedly connected to a first gear, the surface of the first gear is meshed with a transmission belt, one end of the transmission belt passes through the second movable seat and extends to the other side of the second movable seat, the inner ring of the transmission belt is meshed with a second gear, the axis of the second gear is fixedly connected to a transmission shaft, the surface of the transmission shaft is sleeved with a bearing seat for supporting the transmission shaft, the side of the bearing seat close to the second movable seat is fixedly connected to the surface of the second movable seat, both ends of the surface of the transmission shaft are fixedly connected to a third gear, and the outer ring of the C-shaped arm bracket is provided with a tooth groove meshed with the third gear.

[0018] Furthermore, the connecting member includes a connecting column for connection, one side of the connecting column is fixedly connected to the surface of the second movable seat, and the other side of the connecting column contacts the surface of the first movable seat. A screw is provided on one side of the first movable seat, and the threaded end of the screw passes through the first movable seat and extends to the interior of the connecting column, and the surface of the screw is connected to the internal thread of the connecting column.

[0019] Furthermore, a bearing ring for structural limitation is sleeved on the surface of the connecting column, and the surface of the bearing ring is in contact with and matched with the interior of the limiting groove.

[0020] Furthermore, a through hole for the transmission belt to move is provided inside the second movable seat, and a groove for cooperating with the third gear is provided on the surface of the second movable seat.

[0021] Furthermore, a first protective shell for structural protection is fixedly connected to one side of the connecting seat, and a second protective shell is detachably connected to one side of the first protective shell by bolts, a surface of the second protective shell is in contact with a surface of the connecting seat, and openings are provided inside the first protective shell and the second protective shell for use with the C-arm bracket.

[0022] Beneficial effects of the utility model:

[0023] 1. The utility model can be connected to an external device through the connecting seat by arranging a C-shaped arm bracket, an X-ray generator, an image receiver, a limiting groove, a moving structure, a connecting seat and an angle adjustment structure. By starting the angle adjustment structure, the angle adjustment structure drives the C-shaped arm bracket to rotate, and the moving structure limits the C-shaped arm bracket. When adjusted to a suitable position, the X-ray generator generates X-rays, and the generated X-rays penetrate the human body. The image receiver captures the X-rays that penetrate the human body and converts them into visible images.

[0024] 2. The utility model sets a movable structure, so that the second movable wheels can be installed at the four corners of the second movable seat first, and the second movable wheels can be in contact with the outer wall of the C-shaped arm bracket. The first movable wheels can be installed at the four corners of the first movable seat, and the first movable seat and the second movable seat can be connected by a connecting piece, so that the first movable wheel can be in contact with the inner wall of the C-shaped arm bracket, thereby achieving the purpose of limiting and guiding the C-shaped arm bracket.

[0025] 3. The utility model is provided with an angle adjustment structure, which can start the stepper motor, the stepper motor drives the first gear to rotate, the first gear drives the transmission belt to rotate, the transmission belt drives the second gear to rotate, the second gear drives the transmission shaft to rotate, the transmission shaft is limited by the bearing seat, the transmission shaft drives the third gear to rotate, the third gear drives the C-arm bracket to adjust the angle by meshing with the teeth on the surface of the C-arm bracket, so that the C-arm bracket drives the X-ray generator and the image receiver to adjust the appropriate angle.

[0026] 4. The utility model provides a connecting piece, which can be fixedly connected to the second movable seat through one side of the connecting column, and contact the first movable seat with the other side. The screw is passed through the first movable seat and screwed into the interior of the connecting column to achieve the installation connection between the first movable seat and the second movable seat.

[0027] 5. The utility model provides a bearing ring, which can be sleeved on the surface of the connecting column. When the C-shaped arm bracket rotates, the bearing ring contacts the limiting groove inside the C-shaped arm bracket, thereby achieving the purpose of limiting the C-shaped arm bracket.

[0028] 6. The utility model can facilitate the transmission of the transmission toothed belt by setting the through hole and the groove, avoid the contact between the transmission toothed belt and the second movable seat, and reduce the wear of the transmission toothed belt. The groove can avoid the contact between the third gear and the second movable seat, and reduce the wear of the third gear.

[0029] 7. The utility model can protect the movable structure and the angle adjustment structure by providing the first protective shell, the second protective shell and the opening, thereby preventing people or clothing from being drawn into the dangerous situation due to the exposed structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Other features, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0031] Figure 1 It is a three-dimensional structural schematic diagram of the utility model;

[0032] Figure 2 It is a three-dimensional structural schematic diagram of a C-arm bracket and a connecting seat;

[0033] Figure 3 is a three-dimensional structural schematic diagram of a mobile structure;

[0034] Figure 4 It is a schematic diagram of the three-dimensional structure of the mobile structure from another perspective;

[0035] Figure 5 is a schematic diagram of the three-dimensional structure of the connecting piece;

[0036] Figure 6 for Figure 4 A partial enlarged view of point A in the middle.

[0037] In the figure: 1. C-arm bracket; 2. X-ray generator; 3. Image receiver; 4. Limiting groove; 5. Connecting seat; 6. First moving seat; 7. First moving wheel; 8. Second moving seat; 9. Second moving wheel; 10. Stepping motor; 11. First gear; 12. Transmission belt; 13. Second gear; 14. Transmission shaft; 15. Bearing seat; 16. Third gear; 17. Tooth groove; 18. Connecting column; 19. Screw; 20. Bearing ring; 21. Through hole; 22. Groove; 23. First protective shell; 24. Second protective shell; 25. Opening. DETAILED DESCRIPTION

[0038] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific implementation methods.

[0039] See also Figure 1 , Figure 1 It is a structural schematic diagram of the utility model.

[0040] A C-shaped arm of an orthopedic medical device comprises a C-shaped arm bracket 1 for structural support rotation,

[0041] An X-ray generator 2, located at one end of the C-arm support 1, is responsible for generating X-rays;

[0042] An image receiver 3, located at the other end of the C-arm support 1, is used to capture the X-rays that penetrate the human body and convert them into visible images;

[0043] The limiting groove 4 is used for limiting the structure, and the limiting groove 4 is opened inside the C-shaped arm bracket 1;

[0044] A moving structure, used to move on the surface of the C-shaped arm support 1, the surface of the moving structure cooperates with the inside of the limiting groove 4;

[0045] A connecting seat 5 is used for mounting and supporting the C-shaped arm bracket 1, and one side of the connecting seat 5 is fixedly connected to the surface of the mobile structure;

[0046] The angle adjustment structure is used to adjust the angle of the C-shaped arm bracket 1 . The angle adjustment structure is arranged inside the mobile structure and is used in conjunction with the surface of the C-shaped arm bracket 1 .

[0047] See also Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 , Figure 2 is a schematic diagram of the three-dimensional structure of the C-arm support and the connection 5; Figure 3 is a three-dimensional structural schematic diagram of a mobile structure; Figure 4 It is a schematic diagram of the three-dimensional structure of the mobile structure from another perspective; Figure 5 is a schematic diagram of the three-dimensional structure of the connecting piece; Figure 6 for Figure 4 A partial enlarged view of point A in the middle.

[0048] The mobile structure includes a first mobile seat 6 for connection, the first mobile seat 6 is located in the inner ring of the C-shaped arm bracket 1, the four corners of the first mobile seat 6 are movably connected with the first mobile wheel 7, the surface of the first mobile wheel 7 is in contact with the inner ring of the C-shaped arm bracket 1, the outer ring of the C-shaped arm bracket 1 is provided with a second mobile seat 8, the four corners of the second mobile seat 8 are movably connected with the second mobile wheel 9, the surface of the second mobile wheel 9 is in contact with the outer ring of the C-shaped arm bracket 1, and the top and bottom of the first mobile seat 6 are provided with a detachable connecting piece, one side of the connecting piece passes through the C-shaped arm bracket 1 and is fixed to the surface of the second mobile seat 8 The second movable seat 8 is fixedly connected, and the other side of the second movable seat 8 is fixedly connected to the surface of the connecting seat 5. The angle adjustment structure is located on the other side of the second movable seat 8. One end of the angle adjustment structure passes through the second movable seat 8 and is used in conjunction with the surface of the C-shaped arm bracket 1. The second movable wheel 9 can be installed at the four corners of the second movable seat 8 first, and the second movable wheel 9 is in contact with the outer wall of the C-shaped arm bracket 1. The first movable wheel 7 is installed at the four corners of the first movable seat 6, and the first movable seat 6 is connected to the second movable seat 8 through a connecting piece, so that the first movable wheel 7 is in contact with the inner wall of the C-shaped arm bracket 1, so as to achieve the purpose of limiting and guiding the C-shaped arm bracket 1.

[0049] The angle adjustment structure includes a stepper motor 10 for power output, the output end of the stepper motor 10 is fixedly connected to a first gear 11, the surface of the first gear 11 is meshed with a transmission belt 12, one end of the transmission belt 12 passes through the second movable seat 8 and extends to the other side of the second movable seat 8, the inner ring of the transmission belt 12 is meshed with a second gear 13, the axis of the second gear 13 is fixedly connected to a transmission shaft 14, the surface of the transmission shaft 14 is sleeved with a bearing seat 15 for supporting the transmission shaft 14, the side of the bearing seat 15 close to the second movable seat 8 is fixedly connected to the surface of the second movable seat 8, and both ends of the surface of the transmission shaft 14 are fixedly connected to third gears 16, the outer ring of the C-arm bracket 1 is provided with a tooth groove 17 meshing with the third gear 16, and the stepper motor 10 can be started, the stepper motor 10 drives the first gear 11 to rotate, the first gear 11 drives the transmission belt 12 to rotate, the transmission belt 12 drives the second gear 13 to rotate, the second gear 13 drives the transmission shaft 14 to rotate, the transmission shaft 14 is limited by the bearing seat 15, the transmission shaft 14 drives the third gear 16 to rotate, the third gear 16 is meshed with the tooth groove 17 on the surface of the C-arm bracket 1, and drives the C-arm bracket 1 to adjust the angle, so that the C-arm bracket 1 drives the X-ray generator 2 and the image receiver 3 to adjust the appropriate angle.

[0050] The connecting member includes a connecting column 18 for connection, one side of the connecting column 18 is fixedly connected to the surface of the second movable seat 8, and the other side of the connecting column 18 contacts the surface of the first movable seat 6. A screw 19 is provided on one side of the first movable seat 6, and the threaded end of the screw 19 passes through the first movable seat 6 and extends to the interior of the connecting column 18. The surface of the screw 19 is connected to the internal thread of the connecting column 18. It can be fixedly connected to the second movable seat 8 through one side of the connecting column 18, and the other side contacts the first movable seat 6. The screw 19 is passed through the first movable seat 6 and screwed into the interior of the connecting column 18 to realize the installation connection between the first movable seat 6 and the second movable seat 8.

[0051] The surface of the connecting column 18 is sleeved with a bearing ring 20 for structural limitation. The surface of the bearing ring 20 contacts and cooperates with the inside of the limiting groove 4. By sleeved with the bearing ring 20 on the surface of the connecting column 18, when the C-arm bracket 1 rotates, the bearing ring 20 contacts and cooperates with the limiting groove 4 inside the C-arm bracket 1, thereby achieving the purpose of limiting the C-arm bracket 1.

[0052] A through hole 21 for moving the transmission belt 12 is provided inside the second movable seat 8, and a groove 22 for cooperating with the third gear 16 is provided on the surface of the second movable seat 8, which can facilitate the transmission of the transmission belt 12, avoid contact between the transmission belt 12 and the second movable seat 8, and reduce the wear of the transmission belt 12. The groove 22 can avoid contact between the third gear 16 and the second movable seat 8, and reduce the wear of the third gear 16.

[0053] A first protective shell 23 for structural protection is fixedly connected to one side of the connecting seat 5, and a second protective shell 24 is detachably connected to one side of the first protective shell 23 by bolts. The surface of the second protective shell 24 contacts the surface of the connecting seat 5. The interiors of the first protective shell 23 and the second protective shell 24 are both provided with openings 25 for use with the C-arm bracket 1, which can protect the moving structure and the angle adjustment structure to avoid dangerous situations where people or clothing are involved due to exposed structures.

[0054] Working principle: first install the connecting seat 5 on the equipment, install the second moving wheel 9 at the four corners of the second moving seat 8, make the second moving wheel 9 contact with the outer wall of the C-shaped arm bracket 1, install the first moving wheel 7 at the four corners of the first moving seat 6, and fix it with the second moving seat 8 on one side through the connecting column 18, and make the other side contact with the first moving seat 6, screw the screw 19 through the first moving seat 6 and screw it into the inside of the connecting column 18 to achieve the installation connection between the first moving seat 6 and the second moving seat 8, make the first moving wheel 7 contact with the inner wall of the C-shaped arm bracket 1, so as to achieve the purpose of limiting and guiding the C-shaped arm bracket 1, start the stepper motor 10, and the stepper motor 10 drives the first moving wheel 7 to move. A gear 11 rotates, the first gear 11 drives the transmission toothed belt 12 to rotate, the transmission toothed belt 12 drives the second gear 13 to rotate, the second gear 13 drives the transmission shaft 14 to rotate, the transmission shaft 14 is limited by the bearing seat 15, the transmission shaft 14 drives the third gear 16 to rotate, the third gear 16 engages with the tooth groove 17 on the surface of the C-arm bracket 1, drives the C-arm bracket 1 to adjust the angle, so that the C-arm bracket 1 drives the X-ray generator 2 and the image receiver 3 to adjust the appropriate angle, when the C-arm bracket 1 rotates, the bearing ring 20 contacts the limiting groove 4 inside the C-arm bracket 1, so as to achieve the purpose of limiting the C-arm bracket 1.

[0055] In the above-mentioned technology, the X-ray generator 2, the image receiver 3 and the stepper motor 10 are common knowledge in the art, and therefore, no excessive technical description is given in this application document.

[0056] The above shows and describes the basic principles and main features of the utility model and the advantages of the utility model. For those skilled in the art, it is obvious that the utility model is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic features of the utility model. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the utility model is defined by the attached claims rather than the above description, and it is intended to include all changes within the meaning and scope of the equivalent elements of the claims. Any figure mark in the claims should not be regarded as limiting the claims involved.

[0057] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A C-shaped arm of an orthopedic medical device, comprising a C-shaped arm bracket (1) for structural support rotation, characterized in that: An X-ray generator (2), located at one end of the C-arm support (1), is responsible for generating X-rays; An image receiver (3), located at the other end of the C-arm support (1), is used to capture the X-rays that penetrate the human body and convert them into visible images; A limiting groove (4) is used for limiting the position of the structure, and the limiting groove (4) is arranged inside the C-shaped arm bracket (1); A movable structure, used for moving on the surface of the C-shaped arm support (1), the surface of the movable structure being used in cooperation with the interior of the limiting groove (4); A connecting seat (5) used for mounting and supporting the C-shaped arm bracket (1), one side of the connecting seat (5) being fixedly connected to the surface of the moving structure; The angle adjustment structure is used to adjust the angle of the C-shaped arm support (1); the angle adjustment structure is arranged inside the mobile structure and is used in conjunction with the surface of the C-shaped arm support (1).

2. The orthopedic medical device C-arm according to claim 1, characterized in that: The movable structure comprises a first movable seat (6) for connection, the first movable seat (6) being located in the inner ring of the C-shaped arm support (1), the four corners of the first movable seat (6) being movably connected with first movable wheels (7), the surface of the first movable wheel (7) being in contact with and matching with the inner ring of the C-shaped arm support (1), the outer ring of the C-shaped arm support (1) being provided with a second movable seat (8), the four corners of the second movable seat (8) being movably connected with second movable wheels (9), the surface of the second movable wheel (9) being in contact with and matching with the outer ring of the C-shaped arm support (1), the top and bottom of the interior of the first movable seat (6) being provided with detachable connecting pieces, one side of the connecting piece passing through the C-shaped arm support (1) and being fixedly connected with the surface of the second movable seat (8), the other side of the second movable seat (8) being fixedly connected with the surface of the connecting seat (5), the angle adjustment structure being located on the other side of the second movable seat (8), one end of the angle adjustment structure passing through the second movable seat (8) and being used in cooperation with the surface of the C-shaped arm support (1).

3. The orthopedic medical device C-arm according to claim 2, characterized in that: The angle adjustment structure comprises a stepper motor (10) for power output, the output end of the stepper motor (10) is fixedly connected to a first gear (11), the surface of the first gear (11) is meshed with a transmission toothed belt (12), one end of the transmission toothed belt (12) passes through the second movable seat (8) and extends to the other side of the second movable seat (8), the inner ring of the transmission toothed belt (12) is meshed with a second gear (13), the axis of the second gear (13) is fixedly connected to a transmission shaft (14), the surface of the transmission shaft (14) is sleeved with a bearing seat (15) for supporting the transmission shaft (14), the side of the bearing seat (15) close to the second movable seat (8) is fixedly connected to the surface of the second movable seat (8), both ends of the surface of the transmission shaft (14) are fixedly connected to a third gear (16), and the outer ring of the C-shaped arm bracket (1) is provided with a tooth groove (17) meshed with the third gear (16).

4. The orthopedic medical device C-arm according to claim 2, characterized in that: The connecting member comprises a connecting column (18) for connection, one side of the connecting column (18) is fixedly connected to the surface of the second movable seat (8), and the other side of the connecting column (18) is in contact with the surface of the first movable seat (6), and a screw (19) is provided on one side of the first movable seat (6), and the threaded end of the screw (19) passes through the first movable seat (6) and extends to the interior of the connecting column (18), and the surface of the screw (19) is connected to the internal thread of the connecting column (18).

5. The orthopedic medical device C-arm according to claim 4, characterized in that: A bearing ring (20) for structural limiting is sleeved on the surface of the connecting column (18), and the surface of the bearing ring (20) is in contact with and matched with the inside of the limiting groove (4).

6. The orthopedic medical device C-arm according to claim 3, characterized in that: A through hole (21) for moving the transmission belt (12) is provided inside the second movable seat (8), and a groove (22) for cooperating with the third gear (16) is provided on the surface of the second movable seat (8).

7. The orthopedic medical device C-arm according to claim 1, characterized in that: A first protective shell (23) for structural protection is fixedly connected to one side of the connecting seat (5); a second protective shell (24) is detachably connected to one side of the first protective shell (23) via bolts; a surface of the second protective shell (24) contacts a surface of the connecting seat (5); and openings (25) for use with the C-arm bracket (1) are provided inside the first protective shell (23) and the second protective shell (24).

Images