Movement assisting device for peritoneal dialysis weak patient

Abstract

The utility model belongs to the technical field of medical instruments, and particularly discloses a peritoneal dialysis weak patient exercise assisting device which comprises a running machine and anti-falling mechanisms arranged on the front side and the rear side of the running machine. The anti-falling mechanism comprises a supporting rod, a telescopic rod and an arc-shaped protection plate, the supporting rod is vertically arranged, one end of the telescopic rod is connected with the top of the supporting rod, the other end of the telescopic rod is connected with the protruding side of the arc-shaped protection plate, and the concave side of the arc-shaped protection plate faces the human body. By the adoption of the technical scheme, a patient can do whole-body exercises such as slow walking and jogging on the treadmill, the anti-falling mechanism clamps local positions of the front side and the rear side of the patient through the arc-shaped protection plates, and therefore supporting and falling prevention are achieved, and exercises of the patient are not affected.

Description

Technical Field

[0001] This utility model belongs to the field of medical device technology and relates to an exercise assist device for peritoneal dialysis patients who are weak. Background Technology

[0002] The nephrology department is a clinical department established in hospitals at all levels to diagnose and treat kidney diseases. Common renal replacement therapies include kidney transplantation, hemodialysis, and peritoneal dialysis. Peritoneal dialysis is a type of renal replacement therapy that uses the peritoneum as a dialysis membrane, utilizing the principles of diffusion and convection to remove toxins and excess water from the body, thereby maintaining homeostasis and improving overall health. Currently, peritoneal dialysis is primarily used to treat patients with kidney failure.

[0003] Studies show that the average activity level of peritoneal dialysis patients aged 50 is comparable to that of people aged 70, while their activity level is only 50% of that of non-dialysis patients of the same age. This leads to a decline in physical function and quality of life. Peritoneal dialysis patients should avoid heavy physical labor, but can engage in appropriate exercise such as slow walking, jogging, and gymnastics, and try to perform voluntary movements of their hands and feet as much as possible.

[0004] In the prior art, patent CN202322992248.8 discloses a special chair for lower limb rehabilitation exercises for peritoneal dialysis patients, including a base with wheels at the bottom; it also includes two sets of first telescopic rods, the top of which has a sliding engagement mechanism with the motor output end, the first telescopic rod being connected to the bottom of a threaded rod via a first pulley set, and both ends of the threaded rod being rotatably mounted inside the base via bearings, with a sliding rod threadedly connected to the threaded rod, the right end of which is slidably engaged inside the base, and the left end of the base being connected to the top of a second telescopic rod. This device controls the seat body to rise and fall, allowing the patient to sit on the seat and move their legs while suspended in the air. However, the patient remains in a seated position, only able to perform localized leg exercises, with a limited range of motion. Utility Model Content

[0005] The purpose of this invention is to provide an exercise assist device for patients with peritoneal dialysis who are weakened, in order to solve the problem that existing devices only allow patients to perform localized leg exercises and have a limited range of motion.

[0006] To achieve the above objectives, the basic solution of this utility model is: a movement assist device for peritoneal dialysis patients who are weak, including a treadmill and a fall protection mechanism, wherein the fall protection mechanism is arranged on the front and rear sides of the treadmill;

[0007] The fall protection mechanism includes a support rod, a telescopic rod, and an arc-shaped protective plate. The support rod is vertically arranged, one end of the telescopic rod is connected to the top of the support rod, and the other end is connected to the convex side of the arc-shaped protective plate. The concave side of the arc-shaped protective plate faces the human body.

[0008] The working principle and beneficial effects of this basic solution are as follows: This technical solution incorporates a treadmill, allowing patients to perform full-body exercises such as slow walking and jogging, providing a more comprehensive workout. A fall-prevention mechanism ensures safety during exercise. The telescopic rod can extend and adjust the relative position of its connected curved protective plate to the body, moving the plate to either contact or a short distance from the body. With the fall-prevention mechanism positioned on both the front and back sides of the treadmill, the patient is protected by curved protective plates on both sides of their upper body. These plates restrict upper body movement and can also provide support and hold the patient in place, preventing falls without hindering movement. Furthermore, this solution is adaptable to patients of different body types, allowing for flexible adjustment of the telescopic rod's extension and the relative position of the curved protective plate to the patient.

[0009] If necessary, an arc-shaped protective plate can be installed under the patient's armpit, so that the patient's upper limb is located on the outside of the arc-shaped protective plate and does not affect the patient's upper limb movement.

[0010] Furthermore, it also includes an installation slot, a first conveyor belt, a second conveyor belt, and a hand grip;

[0011] The mounting groove is set on the concave arc surface of the arc-shaped protective plate located on the front side of the human body, and the mounting groove is long and narrow.

[0012] The first conveyor belt and the second conveyor belt are both installed in the mounting slot, and the first conveyor belt and the second conveyor belt are symmetrically arranged with respect to the vertical center line of the mounting slot;

[0013] The hand grips are respectively disposed on the belts of the first conveyor belt and the second conveyor belt.

[0014] A mounting slot is provided on the curved protective plate located at the front of the patient, and a conveyor belt is installed within the mounting slot. Hand grips are mounted on the conveyor belt. The position of the curved protective plate can be adjusted using a telescopic rod, maintaining a certain distance between the front protective plate and the patient's body. The patient grips the hand grips and moves their upper limbs with the conveyor belt, thus guiding and assisting upper limb movement. The curved protective plate at the rear of the patient remains in contact with the rear of the body for protection.

[0015] Furthermore, the length of the arc-shaped protective plate located on the front side of the human body is shorter than the length of the arc-shaped protective plate located on the back side of the human body. The arc-shaped protective plate located on the back side of the human body has grooves at both ends, and an extension plate is slidably connected in the grooves.

[0016] The groove is connected to an inflation / deflation mechanism via a first air pipe. An airbag is connected to the outer surface of the extension plate. The airbag is connected to the inflation / deflation mechanism via a second air pipe. A first air valve is provided on the first air pipe, and a second air valve is provided on the second air pipe.

[0017] The length of the arc-shaped protective plate located on the front of the body is shorter than that of the arc-shaped protective plate located on the back of the body. This way, when the extension plate extends, it does not affect the use of the arc-shaped protective plate on the front. At the same time, the arc-shaped protective plate on the back has a larger protection range and better protection effect.

[0018] When the patient grips the handpiece to perform upper limb movements, the front arc-shaped protective plate is far from the patient. At this time, the inflation / deflation mechanism is activated to pour gas into the first and second air tubes, and the first and second air valves are opened. The gas enters the groove and pushes the extension plate out of the groove. At the same time, the gas enters the airbag, causing the airbag to gradually inflate, expanding the protection range of the rear arc-shaped protective plate and optimizing the protection and fall prevention effect.

[0019] Furthermore, it also includes a distance sensor, a pressure sensor, a distance comparator, and a pressure comparator;

[0020] The distance sensor is disposed at the bottom of the groove. The output terminal of the distance sensor is connected to the first input terminal of the distance comparator. The second input terminal of the distance comparator is connected to a distance threshold memory. The output terminal of the distance comparator is connected to the control terminal of the first air valve.

[0021] The pressure sensor is placed inside the airbag. The output of the pressure sensor is connected to the first input of the pressure comparator. The second input of the pressure comparator is connected to a pressure threshold memory. The output of the pressure comparator is connected to the control terminal of the second air valve.

[0022] The distance sensor collects the distance information between the bottom of the groove and the end of the extension plate extending into the groove, and transmits it to the distance comparator. The distance comparator compares the collected distance information value with the distance threshold value stored in the distance threshold memory. If the collected distance signal value is less than the distance threshold, it means that the extension plate has not extended out of the groove to reach the preset distance. At this time, the distance comparator outputs a control signal to the control terminal of the first air valve, controlling the first air valve to open, thereby inflating the groove and causing the extension plate to extend out of the groove.

[0023] Similarly, the pressure sensor collects the pressure signal value inside the airbag and transmits it to the pressure comparator. The pressure comparator compares the collected pressure signal value with the pressure threshold value stored in the pressure threshold memory. When the collected pressure signal value is less than the pressure threshold, it means that the airbag has not reached the inflated state. At this time, the pressure comparator outputs a control signal to the second air valve, controlling the second air valve to open, thereby inflating the airbag.

[0024] Furthermore, it also includes an inflation control button and a deflation control button, which are installed on the outer wall of the arc-shaped protective plate or support rod;

[0025] The output of the inflation control button is connected to the inflation control terminal of the inflation / deflation mechanism, the start terminal of the distance sensor and the pressure sensor, respectively. The output of the deflation control button is connected to the deflation control terminal of the inflation / deflation mechanism, the control terminal of the first air valve and the second air valve.

[0026] The system features control buttons for flexible operation. When the rear curved protective plate needs to be extended, pressing the inflation control button activates the inflation / deflation mechanism, simultaneously activating the distance and pressure sensors for signal detection. Conversely, when the rear curved protective plate extension is not required, pressing the deflation control button releases air, simultaneously opening the first and second air valves.

[0027] Furthermore, the bottom of the support rod is connected to a lift that controls the vertical movement of the support rod.

[0028] A lift is installed to control the raising and lowering of the support rod, thereby adjusting the height of the telescopic rod on the support rod and the arc-shaped protective plate to accommodate patients of different heights and adjust the protective position of the arc-shaped protective plate.

[0029] Furthermore, the outer surface of the arc-shaped protective plate is provided with an elastic protective layer.

[0030] A flexible protective layer is incorporated to make it more comfortable for patients when it comes into contact with them. Attached Figure Description

[0031] Figure 1 This is a front view schematic diagram of the exercise assist device for frail peritoneal dialysis patients according to this utility model;

[0032] Figure 2 This is a top view schematic diagram of the exercise assist device for frail peritoneal dialysis patients according to this utility model;

[0033] Figure 3 This is a schematic diagram of the installation slot for the exercise assist device for frail peritoneal dialysis patients according to this utility model.

[0034] The reference numerals in the accompanying drawings include: treadmill 1, support rod 2, telescopic rod 3, arc-shaped protective plate 4, mounting groove 5, first conveyor belt 6, second conveyor belt 7, hand grip 8, groove 9, extension plate 10, airbag 11, inflation / deflation mechanism 12, distance sensor 13, pressure sensor 14, inflation control button 15, deflation control button 16, and lifting platform 17. Detailed Implementation

[0035] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0036] In the description of this utility model, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0037] In the description of this utility model, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two components. They can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0038] This utility model discloses an exercise assist device for frail peritoneal dialysis patients, such as... Figure 1 and Figure 2 As shown, the device includes a treadmill 1 and an anti-fall mechanism. The treadmill 1 can be an existing fitness treadmill 1 based on a speed belt structure, and the anti-fall mechanism is located on the front and rear sides of the treadmill 1.

[0039] The fall protection mechanism includes a support rod 2, a telescopic rod 3, and an arc-shaped protective plate 4. The support rod 2 is vertically positioned. One end of the telescopic rod 3 is connected to the top of the support rod 2 (e.g., a fixed connection (e.g., welding, bonding, riveting, etc.) or a detachable connection (e.g., snap-fit), and the other end is connected to the protruding side of the arc-shaped protective plate 4 (e.g., welding, bonding, etc.). The concave side of the arc-shaped protective plate 4 faces the human body. The telescopic rod 3 can be an existing pneumatic rod, hydraulic rod, etc., and its length can be flexibly adjusted and positioned. Preferably, the outer surface of the arc-shaped protective plate 4 is provided with an elastic protective layer (e.g., a rubber layer, a sponge layer, etc.) to make the patient more comfortable when the arc-shaped protective plate 4 comes into contact with the patient.

[0040] During use, patients can perform full-body exercises such as slow walking and jogging on the treadmill 1, providing a more comprehensive workout. A fall-prevention mechanism ensures safety during exercise. The telescopic bar 3 can extend and retract to adjust the relative position of its connected curved protective plate 4 to the body. The curved protective plate 4 can be moved to contact the body or at a short distance. With the fall-prevention mechanism located on both the front and back sides of the treadmill 1, the patient on the treadmill 1 is protected by curved protective plates 4 on both sides. These two curved protective plates 4 are positioned around the patient's upper body, restricting upper body movement and providing support to prevent falls without hindering movement. It is also adaptable to patients of different body types, allowing for flexible adjustment of the extension of the telescopic bar 3 and the relative position of the curved protective plate 4 to the patient.

[0041] As needed, the arc-shaped protective plate 4 can be positioned under the patient's armpit, so that the patient's upper limb is located on the outside of the arc-shaped protective plate 4, which does not affect the patient's upper limb movement.

[0042] In a preferred embodiment of this utility model, such as Figure 3 As shown, the exercise aid for frail peritoneal dialysis patients also includes a mounting slot 5, a first conveyor belt 6, a second conveyor belt 7, and a hand grip 8. The mounting slot 5 is located on the concave arc surface of the arc-shaped protective plate 4 located on the front side of the human body, and the mounting slot 5 is elongated.

[0043] Both the first conveyor belt 6 and the second conveyor belt 7 are installed in the mounting groove 5. When the drive and driven wheels of the conveyor belts rotate within the mounting groove 5, the conveyor belts are automatically driven by a motor. The control terminal of the drive motor is electrically connected to a switch button, which can be welded to the corresponding arc-shaped protective plate 4. The start and stop of the conveyor belts can be manually controlled via the switch button for ease of use.

[0044] The first conveyor belt 6 and the second conveyor belt 7 are symmetrically arranged relative to the vertical center line of the mounting groove 5. Hand grips 8 (such as handles or other structures) are respectively installed (e.g., welded, glued, snap-fitted, etc.) on the belt bodies of the first conveyor belt 6 and the second conveyor belt 7. The first conveyor belt 6 and the second conveyor belt 7 can run in the same direction or in opposite directions to perform different upper limb movements.

[0045] An installation groove 5 is provided on the arc-shaped protective plate 4 located on the front side of the body, and a conveyor belt is installed within the installation groove 5. Hand grips 8 are installed on the conveyor belt. The position of the arc-shaped protective plate 4 is adjusted using a telescopic rod 3, allowing the arc-shaped protective plate 4 located on the front side of the body to maintain a certain distance from the patient's body. The patient's hands grip the hand grips 8 and move with the conveyor belt to perform upper limb movements, thus guiding and assisting upper limb movements. The arc-shaped protective plate 4 on the rear side of the patient can still contact the rear side of the patient's body for protection.

[0046] In a preferred embodiment of this utility model, the length of the arc-shaped protective plate 4 located on the front side of the human body is less than the length of the arc-shaped protective plate 4 located on the back side of the human body. The two ends of the arc-shaped protective plate 4 located on the back side of the human body are provided with grooves 9, and extension plates 10 are slidably connected in the grooves 9.

[0047] An inflation / deflation mechanism 12 (such as a miniature fan) is connected to the inside of the groove 9 via a first air pipe. An airbag 11 is connected (e.g., bonded) to the outer surface of the extension plate 10. The airbag 11 is located at the end of the extension plate 10 that extends out of the groove 9. The airbag 11 is connected to the inflation / deflation mechanism 12 via a second air pipe. The inflation / deflation mechanism 12 is fixedly installed on the back of the corresponding arc-shaped protective plate 4. A first air valve is provided on the first air pipe, and a second air valve is provided on the second air pipe. Preferably, the first and second air valves are normally closed electric valves. Alternatively, two buttons can be installed on the arc-shaped protective plate 4 for manual control of the opening and closing of the air valves.

[0048] The length of the arc-shaped protective plate 4 located on the front side of the human body is shorter than the length of the arc-shaped protective plate 4 located on the back side of the human body. This way, when the extension plate 10 extends, it does not affect the use of the arc-shaped protective plate 4 on the front side. At the same time, the arc-shaped protective plate 4 on the back side has a larger protection range and a better protection effect.

[0049] When the patient grips the hand grip piece 8 to perform upper limb movements, the front arc-shaped protective plate 4 is far from the patient. At this time, the inflation / deflation mechanism 12 is activated to pour gas into the first and second air tubes, and the first and second air valves are opened. The gas enters the groove 9 and pushes the extension plate 10 out of the groove 9. At the same time, the gas enters the airbag 11, causing the airbag 11 to gradually inflate, expanding the protection range of the rear arc-shaped protective plate 4 and optimizing the protection and fall prevention effect.

[0050] In a preferred embodiment of this invention, the movement assist device for frail peritoneal dialysis patients further includes a distance sensor 13 (such as a JCS series ultrasonic distance sensor, MD0400 infrared ranging sensor, etc.), a pressure sensor 14 (such as a 26PC01SMT, ZCH304, etc.), a distance comparator, and a pressure comparator. The comparator in this invention can be an analog comparator or a digital comparator. The comparator is preferably, but not limited to, LM324 or LM339. If necessary, a digital-to-analog converter (such as an AK4021) can be set at the first input terminal of the comparator, and the signal output from the sensor passes through the digital-to-analog converter before entering the comparator.

[0051] The distance sensor 13 is located at the bottom of the groove 9. The output terminal of the distance sensor 13 is electrically connected to the first input terminal of the distance comparator. The second input terminal of the distance comparator is electrically connected to a distance threshold memory (such as 24CXX series, 93CXX series, etc.). The output terminal of the distance comparator is electrically connected to the control terminal of the first air valve.

[0052] Pressure sensor 14 is placed inside airbag 11. The output terminal of pressure sensor 14 is electrically connected to the first input terminal of pressure comparator. The second input terminal of pressure comparator is electrically connected to pressure threshold memory. The output terminal of pressure comparator is electrically connected to the control terminal of second air valve.

[0053] Distance sensor 13 collects distance information between the bottom of the groove 9 and the end of the extension plate 10 extending into the groove 9, and transmits it to a distance comparator. The distance comparator compares the collected distance information value with the distance threshold value stored in the distance threshold memory. If the collected distance signal value is less than the distance threshold, it means that the extension plate 10 has not extended out of the groove 9 to reach the preset distance. At this time, the distance comparator outputs a control signal to the control terminal of the first air valve, controlling the first air valve to open, thereby inflating the groove 9 and causing the extension plate 10 to extend out of the groove 9.

[0054] Similarly, pressure sensor 14 collects the pressure signal value inside airbag 11 and transmits it to pressure comparator. Pressure comparator compares the collected pressure signal value with the pressure threshold value in pressure threshold memory. When the collected pressure signal value is less than the pressure threshold, it means that airbag 11 has not reached the inflated state. At this time, pressure comparator outputs a control signal to the second air valve to control the second air valve to open, thereby inflating airbag 11.

[0055] In a preferred embodiment of this utility model, the exercise assistance device for peritoneal dialysis patients with weakness further includes an inflation control button 15 and an deflation control button 16, which are installed (e.g., welded, glued, etc.) on the outer wall of the arc-shaped protective plate 4 or the support rod 2.

[0056] The output terminal of the inflation control button 15 is electrically connected to the inflation control terminal of the inflation / deflation mechanism 12, the start terminal of the distance sensor 13 and the pressure sensor 14, respectively. The output terminal of the deflation control button 16 is electrically connected to the deflation control terminal of the inflation / deflation mechanism 12, the control terminal of the first air valve and the second air valve.

[0057] The system features control buttons for flexible operation. When the rear curved protective plate 4 needs to be extended, pressing the inflation control button 15 activates the inflation / deflation mechanism 12, simultaneously activating the distance sensor 13 and pressure sensor 14 for signal detection. When the rear curved protective plate 4 does not need to be extended, pressing the deflation control button 16 controls the inflation / deflation mechanism 12 to deflate, simultaneously opening the first and second air valves.

[0058] In a preferred embodiment of this utility model, the bottom of the support rod 2 is connected to a lifting mechanism 17 that controls the vertical lifting and lowering of the support rod 2, such as an existing mobile lifting mechanism 17 or a hydraulic lifting mechanism 17. The lifting mechanism 17 can be installed (e.g., riveted, screwed, etc.) on the treadmill 1. By setting up the lifting mechanism 17 to control the lifting and lowering of the support rod 2, the height of the telescopic rod 3 on the support rod 2 and the arc-shaped protective plate 4 can be adjusted to accommodate patients of different heights and to adjust the protective position of the arc-shaped protective plate 4.

[0059] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0060] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A movement assist device for frail peritoneal dialysis patients, characterized in that, It includes a treadmill and a fall protection mechanism, wherein the fall protection mechanism is located on the front and rear sides of the treadmill; The fall protection mechanism includes a support rod, a telescopic rod, and an arc-shaped protective plate. The support rod is vertically arranged, one end of the telescopic rod is connected to the top of the support rod, and the other end is connected to the convex side of the arc-shaped protective plate. The concave side of the arc-shaped protective plate faces the human body.

2. The exercise assist device for frail peritoneal dialysis patients as described in claim 1, characterized in that, It also includes a mounting slot, a first conveyor belt, a second conveyor belt, and a hand grip; The mounting groove is set on the concave arc surface of the arc-shaped protective plate located on the front side of the human body, and the mounting groove is long and narrow. The first conveyor belt and the second conveyor belt are both installed in the mounting slot, and the first conveyor belt and the second conveyor belt are symmetrically arranged with respect to the vertical center line of the mounting slot; The hand grips are respectively disposed on the belts of the first conveyor belt and the second conveyor belt.

3. The exercise assist device for frail peritoneal dialysis patients as described in claim 2, characterized in that, The length of the arc-shaped protective plate located on the front side of the human body is shorter than the length of the arc-shaped protective plate located on the back side of the human body. The arc-shaped protective plate located on the back side of the human body has grooves at both ends, and an extension plate is slidably connected in the grooves. The groove is connected to an inflation / deflation mechanism via a first air pipe. An airbag is connected to the outer surface of the extension plate. The airbag is connected to the inflation / deflation mechanism via a second air pipe. A first air valve is provided on the first air pipe, and a second air valve is provided on the second air pipe.

4. The exercise assist device for frail peritoneal dialysis patients as described in claim 3, characterized in that, It also includes a distance sensor, a pressure sensor, a distance comparator, and a pressure comparator; The distance sensor is disposed at the bottom of the groove. The output terminal of the distance sensor is connected to the first input terminal of the distance comparator. The second input terminal of the distance comparator is connected to a distance threshold memory. The output terminal of the distance comparator is connected to the control terminal of the first air valve. The pressure sensor is placed inside the airbag. The output of the pressure sensor is connected to the first input of the pressure comparator. The second input of the pressure comparator is connected to a pressure threshold memory. The output of the pressure comparator is connected to the control terminal of the second air valve.

5. The exercise assist device for frail peritoneal dialysis patients as described in claim 3, characterized in that, It also includes an inflation control button and a deflation control button, which are installed on the outer wall of the arc-shaped protective plate or support rod; The output of the inflation control button is connected to the inflation control terminal of the inflation / deflation mechanism, the start terminal of the distance sensor and the pressure sensor, respectively. The output of the deflation control button is connected to the deflation control terminal of the inflation / deflation mechanism, the control terminal of the first air valve and the second air valve.

6. The exercise assist device for frail peritoneal dialysis patients as described in claim 1, characterized in that, The bottom of the support rod is connected to a lift that controls the vertical movement of the support rod.

7. The exercise assist device for frail peritoneal dialysis patients as described in claim 1, characterized in that, The outer surface of the arc-shaped protective plate is provided with an elastic protective layer.

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