CN215839996U

CN215839996U - Intelligent wheelchair based on remote control

Info

Publication number: CN215839996U
Application number: CN202121417594.8U
Authority: CN
Inventors: 蔡智勇; 王秀玉
Original assignee: Qingdao Vocational And Technical College Of Hotel Management
Current assignee: Qingdao Vocational And Technical College Of Hotel Management
Priority date: 2021-06-24
Filing date: 2021-06-24
Publication date: 2022-02-18
Anticipated expiration: 2031-06-24

Abstract

The utility model relates to the technical field of wheelchairs. The intelligent wheelchair based on remote control comprises a wheelchair seat, wherein a wheel carrier and an installation frame are arranged at the bottom of the wheelchair seat, universal front wheels, a rear wheel device and a driving motor are arranged below the wheel carrier, a storage battery, a wheelchair control device and a remote control device are fixedly arranged in the wheelchair seat, and a pedal is arranged at the front end of the wheelchair seat; the mounting frame is fixedly provided with an alarm device; the front end face of the mounting frame is provided with a fixed rod, and the upper end face of the fixed rod is fixedly connected with the lower bottom face of the wheelchair seat. The wheelchair seat is provided with a backrest, and the backrest is provided with a safety belt capable of monitoring the heart rate and two cameras; armrests are arranged on two sides of the wheelchair seat and the backrest, and a blood pressure monitoring device and a wheelchair controller are arranged on the front section of the right armrest; the utility model has simple structure and convenient use, can monitor the heart rate and the blood pressure of a user at any time, and can remotely control the movement of the wheelchair through the remote control device.

Description

Intelligent wheelchair based on remote control

Technical Field

The utility model relates to the technical field of wheelchairs, in particular to an intelligent wheelchair based on remote control.

Background

Earlier wheelchairs were manual, being advanced by a person turning a hand wheel, which was physically demanding and not suitable for use by those who were too weak and handicapped. The electric wheelchair is invented subsequently, and generally comprises a vehicle body, front and rear wheels, a driving motor, an operating lever and a motor driver, wherein the driving motor is powered by a storage battery and drives the rear wheels to move forwards, and a person sitting on the wheelchair can realize the forward movement, the backward movement and the left-right turning of the wheelchair only by pressing the operating lever. The electric wheelchair is a great progress over the manual wheelchair, but still has some problems, for example, the children are not around the old and can't observe the physical condition of the old at any time, whether the blood pressure heart rate is normal or meet the accident and lead to the wheelchair to fall down when the old oneself takes the wheelchair to go out, and the children can't learn the message to help the first time. When the child and the old accompany the child and the old take the wheelchair together for going out, the child and the old accompany the child and the old. Therefore, a more excellent transportation tool capable of monitoring the physical condition of the old at any time and informing the young and the young to perform remote control is needed.

SUMMERY OF THE UTILITY MODEL

The utility model discloses an intelligent wheelchair based on remote control, and aims to at least solve the problem that the existing wheelchair can not be used for children and women to know the physical conditions and the traveling conditions of the old at any time.

In order to achieve the purpose, the utility model provides an intelligent wheelchair based on remote control, which comprises a wheelchair seat, wherein the bottom of the wheelchair seat is provided with a wheel carrier and an installation frame, two universal front wheels, two sets of rear wheel devices and two driving motors are arranged below the wheel carrier, a storage battery, a wheelchair control device and a remote control device are fixedly arranged in the wheelchair seat, and the front end of the wheelchair seat is provided with a pedal; the mounting rack is fixedly provided with a remote monitoring device and an alarm device; the front end face of the mounting frame is provided with a supporting rod, and the upper end face of the supporting rod is fixedly connected with the lower bottom face of the wheelchair seat. A backrest is rotatably arranged on the wheelchair seat, and a safety belt capable of monitoring the heart rate and two cameras are arranged on the backrest; a right armrest and a left armrest are mounted on two sides of the wheelchair seat and the backrest, wherein a blood pressure monitoring device and a wheelchair controller are fixedly mounted at the front end of the right armrest; two handles are arranged at the upper end of the back of the backrest.

Compared with the prior art, the utility model has the beneficial effects that:

according to the utility model, the heart rate monitoring device bag is fixedly connected to the safety belt in a penetrating manner, so that the heart rate of the old can be monitored at any time by fastening the safety belt when the old uses the wheelchair. The blood pressure monitoring device is fixedly arranged on the right handrail, so that the blood pressure of the old can be monitored in the wheelchair using process of the old. Through setting up remote control device, need not push away the wheelchair all the time when can satisfying the child and accompany the old man and go on a journey, just can control the wheelchair through supporting software application on the cell-phone and remove, convenient trip. The heart rate and blood pressure monitoring device is electrically connected with the heart rate monitoring device and the blood pressure monitoring device through the remote control device, so that heart rate and blood pressure data of the old can be uploaded to a software application program of the remote control device at any time, and the old can conveniently master the physical condition of the old by children. Through setting up vibration sensor and bee calling organ to with remote control device electric connection, when the old man takes the wheelchair alone and takes place to turn on one's side because of unexpected wheelchair when going out, vibration sensor can be triggered and start the camera through remote control device and take photograph and establish the photo and upload to corresponding customer end and inform young girl, can start bee calling organ simultaneously, attract people around to help. In addition, the anti-falling plate can prevent the left handrail from falling off, and the rotating shaft is rotatably connected to the shaft sleeve, so that the left handrail can rotate downwards, and the old can be conveniently moved down from the wheelchair or moved to the wheelchair.

Drawings

FIG. 1 is a schematic diagram of the right side structure of an embodiment of the present invention;

FIG. 2 is a schematic diagram of the left side structure of the embodiment of the present invention;

FIG. 3 is a rear view of an embodiment of the present invention;

FIG. 4 is a longitudinal cross-sectional view of a heart rate monitoring package of the present invention;

FIG. 5 is a schematic view of the structure at A of the present invention;

fig. 6 is a control relationship diagram of the present invention.

Wherein, the corresponding relationship between the reference numbers and the names of the components in fig. 1 to 6 is;

1. a wheelchair seat; 11. a support plate; 111. mounting a plate; 112. a shaft sleeve; 12. a support pillar; 13. a pedal; 2. a backrest; 21. a handle; 211. a placement groove; 212. an anti-drop plate; 213. a positioning rod; 22. a right armrest; 221. a left armrest; 222. a mounting seat; 223. a blood pressure monitoring device; 224. connecting columns; 23. a seat belt; 231. a slot; 232. a safety belt slot hole; 233. a seatbelt retracting device; 24. a heart rate monitoring package; 241. a penetrating port; 242. a heart rate monitoring device; 25. a camera; 3. a wheel carrier; 31. a universal front wheel; 32. a rear wheel device; 33. a drive motor; 4. a mounting frame; 41. an alarm device; 5. a support bar; 6. a wheelchair control device; 61. a remote control device; 7. a storage battery; 8. a wheelchair controller.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, a more particular description of the utility model will be rendered by reference to the appended drawings. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced otherwise than as specifically described herein, and thus the scope of the present invention is not limited by the specific embodiments disclosed below.

An embodiment of the present invention is described below with reference to fig. 1 to 5.

As shown in fig. 1-3, the intelligent wheelchair based on remote control comprises a wheelchair seat 1, wherein the wheelchair seat 1 is provided with a wheel carrier 3 and an installation frame 4 at the bottom, two universal front wheels 31, two sets of rear wheel devices 32 and two driving motors 33 are arranged below the wheel carrier 3, the two sets of rear wheel devices 32 are driven by the two driving motors 33 to drive the wheelchair to move, and the wheelchair seat 1 is a hollow box body formed by two supporting plates 11 and four supporting columns 12.

Further, a battery 7, a wheelchair control device 6 and a remote control device 61 are fixedly mounted in the wheelchair seat 1.

Further, the wheelchair seat 1 is rotatably provided with a backrest 2, the front end of the wheelchair seat 1 is fixedly provided with a pedal 13, the backrest 2 is provided with a safety belt 23 capable of monitoring the heart rate and two cameras 25, and the upper end of the back of the backrest 2 is provided with two handles 21. The alarm device 41 is fixed on the mounting frame 4; the front end face of the mounting rack 4 is provided with a support rod 5, and the upper end face of the support rod 5 is fixedly connected with the lower bottom face of the wheelchair seat 1.

Further, the wheelchair control device 6 is a control panel with a single chip microcomputer as a core, in this embodiment, the single chip microcomputer may be a single chip microcomputer with a model number of AT89C2051, AT89C1051, AT89C51, AT89S51, or STC12C5a60S2, and the related program belongs to a simple program that can be easily implemented by those skilled in the art by using an existing program development platform and a well-known programming method, is a conventional and adaptive application, and is not described herein again.

Specifically, the slot 231 of the safety belt 23 is fixedly installed at one end of the upper end surfaces of the two support plates 11 close to the backrest 2, and the slot is installed at a position close to the backrest 2 in order to reduce the gap between the safety belt 23 and the human body when the safety belt 23 is fastened, so that the human body can be protected more safely. The upper parts of the left sides of the two supporting plates 11 are fixedly connected with a mounting plate 111, and two sets of shaft sleeves 112 are fixedly connected on the mounting plate 111 for mounting handrails.

As shown in fig. 1 and fig. 2, a right armrest 22 and a left armrest 221 are mounted on two sides of the wheelchair seat 1 and the backrest 2, wherein a blood pressure monitoring device 223 and a wheelchair controller 8 (model number BZ-6310) are fixedly mounted at the front end of the right armrest 22; the rear end of the right armrest 22 is rotatably arranged on the right side edge of the backrest 2, and the lower end of the right armrest 22 is rotatably connected to the upper parts of the right sides of the two supporting plates 11; the front end of the right armrest 22 is fixedly connected with a mounting seat 222, and the wheelchair controller 8 is fixedly mounted on the mounting seat 222.

Specifically, the right armrest 22 is rotatably connected to the backrest 2 and the wheelchair seat 1 via a torque shaft, and the backrest 2 is rotatably connected to the wheelchair seat 1. The side edge of the backrest 2 is provided with the safety belt 23, when the wheelchair is used, the safety belt 23 is taken up, then the safety belt 23 is placed in front of the chest from top to bottom, and then the safety belt is inserted into the slot 231, so that the functions of protecting the safety belt 23 and monitoring the heart rate can be exerted in the process of using the wheelchair. When the right hand is placed on the right armrest 22 and the wheelchair controlled by the wheelchair controller 8 is operated to move, a photoelectric sensor (the model is EPM4001) arranged in the blood pressure monitoring device 223 on the right armrest 22 is in contact with the arm to collect the pulse wave at the wrist, and the pulse wave data is transmitted to the remote control device 61. The blood pressure is monitored by adopting the photoelectric sensor, and the blood pressure monitoring device has the advantages of simple acquisition method and capability of continuously monitoring the blood pressure.

As shown in fig. 1, 2 and 4, a safety belt slot 232 is arranged on the upper portion of the outer side of the left side and the right side of the backrest 2, a safety belt tightening device 233 is fixedly installed on the inner side of the left side and the right side of the backrest 2 corresponding to the position of the safety belt slot 232, a heart rate monitoring bag 24 is crossly connected to the safety belt 23 in a penetrating manner, two crossing ports 241 are arranged on the upper half portion of the heart rate monitoring bag 24, a heart rate monitoring device 242 (with the model of MAX30102) is arranged in the middle position of the lower half portion of the heart rate monitoring bag 24, and the safety belt 23 is fixedly connected in the crossing ports 241 in a penetrating manner; two cameras 25 are fixedly mounted at both ends of the upper side of the backrest 2. When the seat belt 23 is fastened after the wheelchair is seated, the arranged seat belt tightening device 233 can retract the seat belt 23 to a proper length, and the heart rate value can be measured more accurately by adjusting the position of the heart rate monitoring package 24 to the position of the chest.

Further, the heart rate monitoring device 242 monitors the heart rate by using a PhotoPlethysmoGraphy (PPG). The related programs and methods belong to simple programs whose functions can be easily realized by those skilled in the art by using the existing program development platform and well-known programming methods, are conventional and adaptive applications, and are not described in detail herein.

Specifically, a placing groove 211 is formed in the left side edge of the backrest 2, the size of the placing groove 211 is matched with the rear end of the left armrest 221, an anti-falling plate 212 is rotatably connected above the placing groove 211, an arc-shaped clamping groove is formed in the bottom end of the anti-falling plate 212, and a positioning rod 213 is fixedly connected below the placing groove 211. The anti-falling plate 212 is rotated downwards to the position rod 213 to be clamped in the arc-shaped clamping groove, so that the anti-falling plate 212 cannot easily slide down from the position rod due to inertia in the using process of the wheelchair, and the left handrail 221 cannot slide out of the placing groove 221 and fall down. The lower end of the left armrest 221 is further fixedly connected with two connecting posts 224, and two shaft tubes are fixedly connected to the bottom ends of the two connecting posts 224 and are rotatably connected with the two sets of shaft sleeves 112 through two rotating shafts.

As shown in fig. 2 and 5, a connecting column 224 fixedly connected to the lower end of the left handle 221 is rotatably installed in the shaft sleeve 112 through a rotating shaft, and the rear end of the left handle 221 is installed in the placing groove 211, and then the handle is fixedly limited by the anti-dropping plate 212. When the left handrail 221 needs to be put down, the anti-falling plate 212 is rotated outwards to enable the arc-shaped clamping groove to be separated from the positioning rod 213, and then the left handrail 221 is rotated outwards. Thus, the left armrest 221 is lowered to increase the space for the elderly to get on and off the wheelchair.

As shown in fig. 1-3, the bottom surface of the mounting frame 4 is fixedly connected with the wheel frame 3, and two universal front wheels 31 are provided with damping mechanisms; the two sets of rear wheel devices 32 comprise two sets of rear wheels and two sets of brake mechanisms, and the two driving motors 33 are respectively and fixedly connected with the two sets of rear wheel devices 32.

Specifically, the two sets of rear wheel devices 32 and the two driving motors 33 are electrically connected to the wheelchair control device 6. The wheelchair control device 6 is electrically connected with the storage battery 7, the capacity of the storage battery 7 is 35ah, the output voltage is 12V, the remote control device 61 is electrically connected with the wheelchair control device 6, the wheelchair control device 6 is electrically connected with the wheelchair controller 8, and the remote control device 61 is provided with a matched client. The remote control device 61 comprises a communication mechanism, an information collection module (model number is ADAM-4050) and an information processing module (model number is SICSM-S7117); the information collecting module is in signal connection with the information processing module and the information processing module is in signal connection with the communication mechanism; the remote control device 61 is in signal connection with the client, the heart rate monitoring device 242, the blood pressure monitoring device 223 and the camera 25 through a communication mechanism; the remote control device can be connected to a network through the communication mechanism, and the wheelchair can be controlled through the client. The alarm device 41 includes a vibration sensor (model is magnetoelectric HJ-9001) and a buzzer; the alarm device 41 is electrically connected with the remote control device 61; the remote control device 61 and the alarm device 41 are electrically connected to the battery 7.

Further, the client can be a mobile phone or a computer. The communication mechanism can adopt a bluetooth module, a WIFI module or a 4G/5G module, the related programs belong to simple programs which can be easily realized by the technical personnel in the field by using the existing program development platform and the well-known programming method, and the related programs are conventional and adaptive applications and are not described herein. The communication mechanism in this embodiment adopts a WIFI module with model number ESP 8266-01.

The wheelchair can be controlled to advance, turn left, turn right and brake by operating the wheelchair controller 8. The wheelchair controller 8 is controlled to transmit an electric signal to the wheelchair control device 6, then the rotating speeds of the two driving motors are adjusted, the rotating speed of the left rear wheel is adjusted and reduced during left turning, and the rotating speed of the right rear wheel is kept unchanged, so that left turning can be realized; when the vehicle turns right, the rotating speed of the right rear wheel is reduced, and the right turning can be realized by keeping the rotating speed of the left rear wheel unchanged; as shown in fig. 6, after the elderly use the wheelchair and fasten the safety belt, the wheelchair controller 8 is controlled to send an electric signal to the wheelchair control device 6 to control the wheelchair, the wheelchair can place the arm on the blood pressure monitoring device, the heart rate monitoring device 242 and the blood pressure monitoring device 223 can send the monitored human body information to the remote control device 61, the information is sent to the communication mechanism through the information collection module and the information processing module, and finally the information is uploaded to the client, so that the purpose of remotely monitoring the physical condition of the elderly is achieved.

As shown in fig. 6, when the wheelchair is remotely controlled by the client, the client transmits an electric signal to the remote control device 61, and then transmits the electric signal to the wheelchair control device 6, and then controls the wheelchair to move. When the wheelchair turns over unexpectedly, the vibration sensor in the alarm device 41 is triggered, the vibration sensor sends an electric signal to the remote control device 61, the electric signal is processed, the buzzer is controlled to start working, the sound is made to attract people around to come and help, meanwhile, the information processing module sends the electric signal to the camera 25, the camera 25 is started to shoot a picture, the picture is transmitted to the information collecting module, the picture is processed by the information processing module, and the picture is uploaded to a corresponding client side through the communication mechanism to inform a child.

Principle of operation

When the device provided by the utility model is used, the anti-drop plate 212 can be firstly rotated outwards to enable the arc-shaped clamping groove to be separated from the positioning rod 213, and then the left handrail 221 can be placed downwards by rotating outwards. Thus, the left armrest 221 is lowered to increase the space for the elderly to get on and off the wheelchair. Sit the back with left handrail playback earlier, then take safety belt 23 up, with safety belt 23 top-down place the chest before, then insert in slot 231, the safety belt tightening means 233 that sets up on the back 2 can retrieve suitable length with safety belt 23, then the position of adjusting heart rate monitoring package 24 to the position of chest, the process of using this wheelchair like this can only exert the guard action of safety belt 23 and the effect of heart rate monitoring device 242 monitoring heart rate. The right hand is placed on the right armrest 22, the wheelchair controlled by the wheelchair controller 8 is controlled to move, and meanwhile, the blood pressure monitoring device 223 arranged on the right armrest 22 is in contact with the arm to monitor the blood pressure, and then the monitored data is uploaded to the communication equipment of the children through the remote control device 61. When the wheelchair is turned over accidentally, the alarm device 41 is triggered, an electric signal is sent to the remote control device 61, the alarm device 41 starts to work to make a sound to attract people around to help, meanwhile, the information processing module sends the electric signal to the camera 25, the camera 25 is started to shoot a photo, the photo is transmitted to the information collecting module, the photo is processed by the information processing module, and the photo is uploaded to a corresponding client through the communication mechanism to notify the child. When the wheelchair is remotely controlled through the client, the client sends an electric signal to the remote control device 61 through the communication mechanism, and then transmits the electric signal to the wheelchair control device 6 to control the two sets of rear wheel devices. The wheelchair can move forward by keeping the same rotating speed of the two driving motors, the rotating speed of the two driving motors is adjusted, the left-right turning of the wheelchair can be realized, the rotating speed of the left rear wheel is adjusted and reduced during the left turning, and the rotating speed of the right rear wheel is kept unchanged, so that the left turning can be realized; when the automobile turns right, the rotating speed of the right rear wheel is reduced, and the right turning can be realized by keeping the rotating speed of the left rear wheel unchanged.

In the present invention, the terms "mounting," "connecting," "fixing," and the like are used in a broad sense, for example, "connecting" may be a fixed connection, a detachable connection, or an integral connection; "coupled" may be direct or indirect through an intermediary. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

In the present invention, the terms "upper", "lower", "left", "right", "middle", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting.

Claims

1. The utility model provides an intelligence wheelchair based on remote control, includes wheelchair seat (1), its characterized in that: the wheelchair comprises a wheelchair seat (1), wherein a wheel carrier (3) and a mounting frame (4) are mounted at the bottom of the wheelchair seat (1), two universal front wheels (31), two sets of rear wheel devices (32) and two driving motors (33) are arranged below the wheel carrier (3), a storage battery (7), a wheelchair control device (6) and a remote control device (61) are fixedly mounted in the wheelchair seat (1), and a pedal (13) is arranged at the front end of the wheelchair seat (1); an alarm device (41) is fixedly arranged on the mounting rack (4); a support rod (5) is arranged on the front end face of the mounting frame (4), the upper end face of the support rod (5) is fixedly connected with the lower bottom face of the wheelchair seat (1), a backrest (2) is rotatably mounted on the wheelchair seat (1), and a safety belt (23) and two cameras (25) are mounted on the backrest (2); a right armrest (22) and a left armrest (221) are mounted on two sides of the wheelchair seat (1) and the backrest (2), wherein a blood pressure monitoring device (223) and a wheelchair controller (8) are fixedly mounted at the front end of the right armrest (22); two handles (21) are arranged at the upper end of the back of the backrest (2).

2. The intelligent wheelchair based on remote control as claimed in claim 1, wherein: the wheelchair seat comprises a wheelchair seat body (1), a wheelchair seat body and a wheelchair seat, wherein the wheelchair seat body comprises two supporting plates (11) and four supporting columns (12), the upper end face of each supporting plate (11) is close to one end of a backrest (2) is fixedly provided with a slot (231) of a safety belt (23), the two ends of each supporting plate are fixedly connected with a mounting plate (111) on the upper portion of the left side of each supporting plate (11), and the two sets of shaft sleeves (112) are fixedly connected on the mounting plates (111).

3. The intelligent wheelchair based on remote control as claimed in claim 1, wherein: the bottom surface of the mounting rack (4) is fixedly connected with the wheel carrier (3), and two universal front wheels (31) are provided with damping mechanisms; the two sets of rear wheel devices (32) comprise two sets of rear wheels and two sets of brake mechanisms, the two driving motors (33) are respectively and fixedly connected with the two sets of rear wheel devices (32), and output shafts of the two driving motors (33) are respectively in rotating connection with the two sets of rear wheels; the two sets of rear wheel devices (32) and the two driving motors (33) are electrically connected with the wheelchair control device (6).

4. The intelligent wheelchair based on remote control as claimed in claim 1, wherein: the wheelchair control device (6) is electrically connected with the storage battery (7), the remote control device (61) is electrically connected with the wheelchair control device (6), and the wheelchair control device (6) is electrically connected with the wheelchair controller (8).

5. The intelligent wheelchair based on remote control as claimed in claim 4, wherein: the remote control device (61) comprises a communication mechanism, an information collection module and an information processing module; the information collection module is in signal connection with the information processing module, and the information collection module is in signal connection with the communication mechanism; the remote control device (61) is in signal connection with the client, and the remote control device (61) is electrically connected with the heart rate monitoring device (242), the blood pressure monitoring device (223) and the camera (25); the alarm device (41) comprises a vibration sensor and a buzzer, and the alarm device (41) is electrically connected with the remote control device (61); the remote control device (61) and the alarm device (41) are electrically connected with the storage battery (7).

6. The intelligent wheelchair based on remote control as claimed in claim 1, wherein: safety belt slotted holes (232) are formed in the upper portions of the outer sides of the left side and the right side of the backrest (2), safety belt tightening devices (233) are fixedly installed on the inner sides of the left side and the right side of the backrest (2) in positions corresponding to the safety belt slotted holes, heart rate monitoring packages (24) are crossed and connected to the safety belts (23), two cross-over penetrating ports (241) are formed in the upper portion of each heart rate monitoring package (24), a heart rate monitoring device (242) is arranged in the middle of the lower portion of each heart rate monitoring package (24), and the safety belts (23) are fixedly penetrated and connected into the corresponding penetrating ports (241); the two cameras (25) are fixedly arranged at two ends of the upper side edge of the backrest (2).

7. The intelligent wheelchair based on remote control as claimed in claim 2, wherein: the rear end of the right armrest (22) is rotatably mounted on the right side of the backrest (2), and the lower end of the right armrest (22) is rotatably connected to the upper parts of the right sides of the two support plates (11); the front end of the right armrest (22) is fixedly connected with a mounting seat (222), and the wheelchair controller (8) is fixedly mounted on the mounting seat (222).

8. The intelligent wheelchair based on remote control as claimed in claim 2, wherein: a placing groove (211) is formed in the left side edge of the backrest (2), the size of the placing groove (211) is matched with the rear end of the left handrail (221), an anti-falling plate (212) is rotatably connected above the placing groove (211), an arc-shaped clamping groove is formed in the bottom end of the anti-falling plate (212), and a positioning rod (213) is fixedly connected below the placing groove (211); the lower end of the left handrail is also fixedly connected with two connecting columns (224) and two shaft tubes fixedly connected with the bottom ends of the two connecting columns (224), and the two shaft tubes are rotatably connected with the two groups of shaft sleeves (112) through two rotating shafts.