A device for preventing the elderly from falling when going up and down stairs

Abstract

The utility model discloses an old person stair climbing and descending anti-falling device relates to stair auxiliary device technical field, and this old person stair climbing and descending anti-falling device, including L shaped board, L shaped board fixed connection in the length direction of stair handrail one side of handrail, and the sliding block is slidably connected on the fixed track board of one side of L shaped board. The utility model discloses a rotatable horizontal plate can be unfolded and closed, by setting support component on the horizontal plate, and the support component is used for the support of protection component, and the main part of protection component is two rotatable restraint plates, and the body of old person is placed in two restraint plates, forms the safety protection effect, when the body of old person falls, has the risk of falling down, can drive restraint plate, support plate and moves down to make the push block respectively with first switch, second switch contact, on one hand realizes the braking effect of device, and secondly can alarm, and timely causes the attention of family, and timely carries out the rescue.

Description

Technical Field

[0001] This utility model relates to the technical field of staircase auxiliary devices, specifically a device to prevent elderly people from falling when going up and down stairs. Background Technology

[0002] As people age, their bone density decreases, muscle strength weakens, and balance declines, making them more prone to falls when going up and down stairs. Due to osteoporosis, falls in the elderly can pose serious safety risks, necessitating the use of fall protection devices. These devices provide additional support and reduce the risk of falls. For example, patent application CN201911304287.6 discloses a fall protection device for the elderly going up and down stairs. This solution uses multiple braking devices on the main body to achieve an emergency braking function, thus providing some fall protection. However, it still has certain defects and shortcomings in use. First, the device cannot guide the elderly to move slowly, as going up and down stairs is quite strenuous for them. Second, the device lacks protective and support components for the elderly's body, resulting in insufficient safety. Third, it does not automatically brake or trigger an alarm when an elderly person falls. Therefore, improvements are needed. Utility Model Content

[0003] This utility model provides a fall prevention device for the elderly going up and down stairs. It has the advantages of high safety and good protection effect. The device is foldable, which can reduce the space occupied when not in use. It also has automatic braking and alarm functions to solve the problems of insufficient safety protection effect and lack of automatic braking and alarm functions in the current stage.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a fall prevention device for the elderly going up and down stairs, comprising an L-shaped plate, the L-shaped plate being fixedly connected to one side of the handrail along the length of the stair railing, and a sliding block being slidably connected to a track plate fixed to one side of the L-shaped plate, a support being fixedly connected to one side of the sliding block, a horizontal plate being rotatably connected to a support plate fixed to the lower surface of the support, a support component being provided on the horizontal plate, and a protective component being installed on the top of the support component, the protective component comprising an installation frame being fixedly connected to the top of the support component; and irregular gears, ear plates being fixedly connected to both sides of the installation frame, two irregular gears being provided and rotatably connected to the corresponding ear plates, a fixing member being fixedly connected to one side of each of the two irregular gears, and a restraining plate being provided at the end of each fixing member.

[0005] As a preferred embodiment of this utility model, a toothed plate is fixedly connected to the L-shaped plate, and a first motor is installed on one side of the support. A small gear is coaxially fixed on one side of the first motor, and the small gear meshes with the toothed plate.

[0006] As a preferred embodiment of this utility model, a mounting plate is fixedly connected to one side of the support plate, and a first electric push rod is rotatably connected between the mounting plate and the cross plate.

[0007] As a preferred embodiment of this utility model, the supporting component includes two round rods slidably connected to the horizontal plate, and a support plate is fixedly connected to the upper end of the two round rods. The support plate is fixedly connected to the mounting frame, and a spring is sleeved on the round rod. The two ends of the spring abut against the horizontal plate and the support plate, respectively. A protective cap is fixedly connected to the lower end of the round rod, and a damping ring is provided between the protective cap and the horizontal plate. A first switch and a second switch are respectively installed on the upper surface of the horizontal plate, and a toggle block is fixed on the lower surface of the support plate corresponding to the first switch and the second switch. The first switch is connected in series with the first motor.

[0008] As a preferred embodiment of this utility model, an alarm is installed on one side of the horizontal plate, and the alarm is connected in series with the second switch. The alarm is a buzzer.

[0009] As a preferred technical solution of this utility model, a soft pad is fixedly connected to the inner wall of the restraint plate, and a slider is slidably connected to the limiting plate fixed on the upper surface of the mounting frame, and a double-sided rack is fixedly connected to the slider, the double-sided rack meshing with two irregular gears.

[0010] As a preferred embodiment of this utility model, a second electric push rod is installed on the inner side of the mounting frame, and a traction frame is fixedly connected to the end of the output shaft of the second electric push rod. The traction frame is connected and fixedly connected to the double-sided rack.

[0011] As a preferred technical solution of this utility model, two symmetrically distributed sliding grooves are provided on the horizontal plate, and a support component is provided on each of the two sliding grooves. The support component includes a sleeve slidably connected to the sliding groove and a telescopic plate slidably connected to the sleeve. A base plate is fixedly connected to a support frame provided on the top of the telescopic plate, and a handle and a protective pad are respectively provided on the upper surface of the base plate.

[0012] As a preferred technical solution of this utility model, a locking rod is threadedly connected to the screw hole on one side of the sleeve. The locking rod is a screw, and a locking groove is provided on one side of the telescopic plate at equal intervals.

[0013] As a preferred technical solution of this utility model, a telescopic control mechanism is installed on one side of the horizontal plate. The telescopic control mechanism includes a protective frame installed on one side of the horizontal plate and a bidirectional lead screw rotatably connected to the protective frame. Two symmetrically distributed slides are threaded onto the bidirectional lead screw. A traction member is fixedly connected to one side of the slide and is connected and fixedly connected to a corresponding sleeve. A limit rod is fixedly connected to the protective frame. A limit hole adapted to the limit rod is opened on the slide corresponding to the limit rod. A second motor for controlling the rotation of the bidirectional lead screw is installed on one side of the protective frame.

[0014] Compared with the prior art, this utility model provides a fall prevention device for the elderly going up and down stairs, which has the following beneficial effects:

[0015] 1. This anti-fall device for elderly people going up and down stairs consists of an L-shaped plate fixed to one side of the stair handrail, with a sliding support and a horizontal plate mounted on the L-shaped plate via a track plate. The horizontal plate is rotatably connected to the support plate and can be folded when not in use to save space. The movement of the support is controlled by a first motor, a pinion gear, and a toothed plate, enabling stable movement of the support and the horizontal plate. The elderly person can move the device by holding the support component. Because the device moves at a stable speed, it can reduce the accident rate and ensure safety. Moreover, this method of use is relatively effortless and convenient for the elderly.

[0016] 2. This anti-fall device for elderly people going up and down stairs uses a support component on a horizontal plate, on which a protective component is fixed. The protective component includes two rotatable restraint plates with an irregular shape. When the two restraint plates are brought together, they form an ellipse. The elderly person's body is placed within the ellipse, providing excellent safety protection. When the elderly person accidentally falls and their body moves downward, their body controls the restraint plates, the mounting frame, and the support plate to move downward. At this time, a lever contacts two switches. The first switch is connected in series with the first motor, stopping the first motor and thus achieving its automatic braking function to prevent further harm. At the same time, the alarm is connected in series with the second switch, causing the alarm to activate automatically and triggering an alert so that family members can be notified in time to resolve the danger. Therefore, this device has good safety, automatic braking, and alarm functions, making it very suitable for the elderly. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of one side of the present invention;

[0018] Figure 2 This utility model Figure 1 Enlarged view of the structure at point A in the middle;

[0019] Figure 3 This is a schematic diagram of the supporting component in this utility model;

[0020] Figure 4 This is a schematic diagram of the structure of the protective component in this utility model;

[0021] Figure 5 This utility model Figure 4 Enlarged view of the structure at point B;

[0022] Figure 6 This is a schematic diagram of the supporting component in this utility model;

[0023] Figure 7 This is a three-dimensional structural diagram of the other side of the present invention;

[0024] Figure 8 This is a schematic diagram of the telescopic control mechanism in this utility model.

[0025] In the diagram: 1. L-shaped plate; 2. Support plate; 3. Mounting plate; 4. First electric push rod; 5. Horizontal plate; 6. Support component; 601. Round rod; 602. Spring; 603. Support plate; 604. Toggle block; 605. Protective cap; 606. Damping ring; 607. First switch; 608. Second switch; 7. Protective component; 701. Mounting frame; 702. Ear plate; 703. Irregular gear; 704. Fixing component; 705. Restraint plate; 706. Soft pad; 707. Double-sided rack; 708. Limiting plate; 709. Slider; 7010. Traction frame ; 7011, Second electric push rod; 8, Support component; 801, Sleeve; 802, Telescopic plate; 803, Support frame; 804, Base plate; 805, Handle; 806, Protective pad; 807, Locking rod; 9, Slide groove; 10, Alarm; 11, Track plate; 12, Sliding block; 13, Support; 14, Pinion; 15, First motor; 16, Tooth plate; 17, Telescopic control mechanism; 1701, Protective frame; 1702, Limiting rod; 1703, Traction component; 1704, Two-way lead screw; 1705, Slide seat; 1706, Second motor. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] Please see Figures 1-8This utility model discloses a fall prevention device for the elderly going up and down stairs, including an L-shaped plate 1. The L-shaped plate 1 is fixedly connected to one side of the handrail along the length of the stair handrail. The L-shaped plate 1 is designed according to the shape of the stair handrail and is used for the installation of other components. A sliding block 12 is slidably connected to a track plate 11 fixed to one side of the L-shaped plate 1. The track plate 11 is used to limit the sliding of the sliding block 12. A support 13 is fixedly connected to one side of the sliding block 12. A horizontal plate 5 is rotatably connected to a support plate 2 fixed to the lower surface of the support 13, so that the horizontal plate 5 can rotate. When the device is not in use, the horizontal plate 5 can be folded to avoid obstructing the stair passage.

[0028] A support component 6 is provided on the horizontal plate 5, and a protective component 7 is installed on the top of the support component 6. The support component 6 is used to support the installation of the protective component 7. The protective component 7 can protect the elderly and reduce the fall accident rate. The protective component 7 includes a mounting frame 701, which is fixedly connected to the top of the support component 6.

[0029] It also features a special-shaped gear 703. Ear plates 702 are fixedly connected to both sides of the mounting frame 701. Two special-shaped gears 703 are provided and rotatably connected to the corresponding ear plates 702. Fixing members 704 are fixedly connected to one side of each of the two special-shaped gears 703, and restraint plates 705 are provided at the ends of the fixing members 704. The special-shaped gears 703 can rotate. When rotating, the restraint plates 705 are rotated through the fixing members 704, adjusting the angle and usage state of the restraint plates 705. Before use, the two restraint plates 705 are in the unfolded state. The elderly person enters the inside of the two restraint plates 705. Then, the special-shaped gears 703 rotate, causing the two restraint plates 705 to close, forming a safe elliptical area, thereby achieving the safety protection of the elderly person's body.

[0030] Specifically, a toothed plate 16 is fixedly connected to the L-shaped plate 1, and a first motor 15 is installed on one side of the support 13. A pinion 14 is coaxially fixed on one side of the first motor 15, and the pinion 14 meshes with the toothed plate 16.

[0031] In this embodiment, the first motor 15 can drive the pinion 14 to rotate, and the pinion 14 meshes with the toothed plate 16, thereby controlling the support 13 to move, so that the sliding block 12 slides on the track plate 11, realizing the movement control of the support plate 2 and the cross plate 5. This movement method is stable and can move stably along the direction of the stairs, which is suitable for the elderly to use.

[0032] Specifically, a mounting plate 3 is fixedly connected to one side of the support plate 2, and a first electric push rod 4 is rotatably connected between the mounting plate 3 and the cross plate 5.

[0033] In this embodiment, the first electric push rod 4 can control the rotation of the horizontal plate 5 when it extends or retracts, thereby controlling the horizontal plate 5 to close or straighten.

[0034] Specifically, the support component 6 includes two round rods 601 slidably connected to the horizontal plate 5, and a support plate 603 is fixedly connected to the upper end of the two round rods 601. The support plate 603 is connected and fixed to the mounting frame 701, and a spring 602 is sleeved on the round rod 601. The two ends of the spring 602 abut against the horizontal plate 5 and the support plate 603 respectively. A protective cap 605 is fixedly connected to the lower end of the round rod 601. A damping ring 606 is provided between the protective cap 605 and the horizontal plate 5. A first switch 607 and a second switch 608 are respectively installed on the upper surface of the horizontal plate 5. A toggle block 604 is fixed on the lower surface of the support plate 603 corresponding to the first switch 607 and the second switch 608. The first switch 607 is connected in series with the first motor 15.

[0035] In this embodiment, the round rod 601 is slidably connected to the horizontal plate 5, and the support plate 603 is connected and fixed to the mounting frame 701 to realize the supporting function of the protective component 7. By setting the spring 602, the support plate 603 forms an elastic supporting function. When the elderly are at risk of falling and their body moves down uncontrollably, the protective component 7 can be moved down, which will drive the support plate 603 and the round rod 601 down. At this time, the toggle block 604 contacts the first switch 607. The first switch 607 is connected in series with the first motor 15, which then disconnects the circuit of the first motor 15, causing the first motor 15 to stop working and then perform a braking function to ensure the safety of the elderly and avoid further accidents.

[0036] Specifically, an alarm 10 is installed on one side of the horizontal plate 5. The alarm 10 is connected in series with the second switch 608. The alarm 10 is a buzzer.

[0037] In this implementation scheme, the alarm 10 can generate an alarm function. When the toggle block 604 contacts the second switch 608, it can connect the power supply circuit of the alarm 10, so that the alarm 10 can work and attract the attention of family members or caregivers in time to provide timely assistance.

[0038] Specifically, a soft pad 706 is fixedly connected to the inner wall of the restraint plate 705, and a slider 709 is slidably connected to the limiting plate 708 fixed on the upper surface of the mounting frame 701. A double-sided rack 707 is fixedly connected to the slider 709, and the double-sided rack 707 meshes with two irregular gears 703.

[0039] In this embodiment, the setting of the limiting plate 708 and the slider 709 can realize the stable movement of the double-sided rack 707. The double-sided rack 707 meshes with two irregular gears 703. When the double-sided rack 707 extends or retracts, it can control the rotation of the irregular gears 703, which in turn drives the binding plate 705 to rotate, adjusting the closed state of the two binding plates 705.

[0040] Specifically, a second electric push rod 7011 is installed on the inner side of the mounting frame 701. A traction frame 7010 is fixedly connected to the end of the output shaft of the second electric push rod 7011. The traction frame 7010 is connected and fixed to the double-sided rack 707.

[0041] In this embodiment, the second electric push rod 7011 can control the extension and retraction of the traction frame 7010. The traction frame 7010 is connected and fixed to the double-sided rack 707, thereby realizing the extension and retraction control of the double-sided rack 707.

[0042] Specifically, the horizontal plate 5 has two symmetrically distributed sliding grooves 9, and each sliding groove 9 is provided with a support component 8. The support component 8 includes a sleeve 801 slidably connected to the sliding groove 9, and a telescopic plate 802 slidably connected to the sleeve 801. A base plate 804 is fixedly connected to a support frame 803 provided on the top of the telescopic plate 802. A handle 805 and a protective pad 806 are respectively provided on the upper surface of the base plate 804.

[0043] In this embodiment, the sliding groove 9 allows the support component 8 to extend and retract, adjusting the distance between the two support components 8 to suit the needs of the elderly. Furthermore, when the two support components 8 move outwards, they create a clearance, preventing interference when the restraint plate 705 rotates outwards, thus ensuring the normal rotation of the restraint plate 705. The support component 8 provides support for the elderly person's arm. A telescopic block adapted to the sliding groove 9 is provided on the lower surface of the sleeve 801 to limit the movement of the sleeve 801. The telescopic plate 802 can extend and retract on the sleeve 801, adjusting the overall height of the support component 8 as needed. By providing a handle 805 and a protective pad 806 on the base plate 804, the elderly person's arm can rest on the protective pad 806, and they can hold the handle 805 for stable movement.

[0044] Specifically, a locking rod 807 is threadedly connected to the screw hole on one side of the sleeve 801. The locking rod 807 is a screw, and a locking groove is provided on one side of the telescopic plate 802 at equal intervals.

[0045] In this embodiment, when the locking rod 807 rotates, it can close to the corresponding locking groove to achieve locking and positioning of the telescopic plate 802.

[0046] Specifically, a telescopic control mechanism 17 is installed on one side of the horizontal plate 5. The telescopic control mechanism 17 includes a protective frame 1701 installed on one side of the horizontal plate 5, and a bidirectional lead screw 1704 rotatably connected to the protective frame 1701. Two symmetrically distributed slide blocks 1705 are threaded onto the bidirectional lead screw 1704. A traction member 1703 is fixedly connected to one side of the slide block 1705. The traction member 1703 is connected and fixed to the corresponding sleeve 801. A limit rod 1702 is fixedly connected to the protective frame 1701. A limit hole adapted to the limit rod 1702 is opened on the slide block 1705 at the corresponding limit rod 1702. A second motor 1706 for controlling the rotation of the bidirectional lead screw 1704 is installed on one side of the protective frame 1701.

[0047] In this embodiment, the telescopic control mechanism 17 can control the movement of the support component 8 and adjust the distance between the two support components 8. During adjustment, it can control the second motor 1706 to work. The second motor 1706 drives the bidirectional lead screw 1704 to rotate. When the bidirectional lead screw 1704 rotates, it can make the two slides 1705 move towards each other. By setting the traction member 1703 on the slide 1705 and connecting and fixing the traction member 1703 to the corresponding sleeve 801, the movement control of the sleeve 801 can be realized.

[0048] It should be noted that both the first electric push rod 4 and the second electric push rod 7011 have a self-locking function, and both the first motor 15 and the second motor 1706 are self-locking motors.

[0049] The working principle and usage process of this utility model are as follows: First, the restraint plates 705 are opened, and the elderly person enters the inner side of the two restraint plates 705. Then, the two restraint plates 705 are closed, placing the elderly person within the elliptical area formed between the two restraint plates 705. During operation, the double-sided rack 707 can be moved by the second electric push rod 7011. The double-sided rack 707 meshes with two irregular gears 703. When the double-sided rack 707 moves, it drives the irregular gears 703 to rotate. The rotation of the irregular gears 703 drives the restraint plates 705 to rotate, thus realizing the rotation control of the restraint plates 705. When the elderly person goes up or down stairs, their arms are placed on the protective pad 806, and their hands are on the handle 805. Then, the first electric push rod 7011 is controlled. When the motor 15 is in operation, the first motor 15 drives the pinion 14 to rotate. The pinion 14 meshes with the gear plate 16, which in turn causes the support 13 and the sliding block 12 to move along the track plate 11, and drives the support plate 2 and the cross plate 5 to move. When the elderly person accidentally falls and their body falls, the restraint plate 705, the support plate 603, and the round rod 601 can move down, so that the toggle block 604 can contact the first switch 607 and the second switch 608. The first switch 607 can control the first motor 15 to stop working, thereby achieving its braking effect and preventing the occurrence of further danger. At the same time, the second switch 608 connects the circuit of the alarm 10, so that the alarm 10 can work, thereby attracting attention in time, and family members or caregivers can provide assistance immediately.

[0050] In conclusion, this anti-fall device for elderly people going up and down stairs has good safety protection, is easy to use, and has emergency braking and automatic alarm functions, making it suitable for use by the elderly.

[0051] It should be noted that, in this document, terms such as "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0052] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art 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 appended claims and their equivalents.

Claims

1. A fall prevention device for the elderly going up and down stairs, characterized in that: The staircase includes an L-shaped plate (1) fixedly connected to one side of the handrail along its length. A sliding block (12) is slidably connected to a track plate (11) fixed to one side of the L-shaped plate (1). A support (13) is fixedly connected to one side of the sliding block (12). A horizontal plate (5) is rotatably connected to a support plate (2) fixed to the lower surface of the support (13). A support member (6) is provided on the horizontal plate (5), and a protective member (7) is installed on the top of the support member (6). The protective member (7) includes... Mounting frame (701), said mounting frame (701) is fixedly connected to the top of the support member (6); and The irregular gear (703) has ear plates (702) fixedly connected to both sides of the mounting frame (701). There are two irregular gears (703) and they are rotatably connected to the corresponding ear plates (702). One side of each of the two irregular gears (703) is fixedly connected to a fastener (704), and the end of each fastener (704) is provided with a restraining plate (705).

2. The anti-fall device for elderly people going up and down stairs according to claim 1, characterized in that: A toothed plate (16) is fixedly connected to the L-shaped plate (1), and a first motor (15) is installed on one side of the support (13). A small gear (14) is coaxially fixed on one side of the first motor (15), and the small gear (14) meshes with the toothed plate (16).

3. The anti-fall device for elderly people going up and down stairs according to claim 1, characterized in that: A mounting plate (3) is fixedly connected to one side of the support plate (2), and a first electric push rod (4) is rotatably connected between the mounting plate (3) and the cross plate (5).

4. The anti-fall device for elderly people going up and down stairs according to claim 2, characterized in that: The support component (6) includes two round rods (601) slidably connected to the horizontal plate (5), and a support plate (603) is fixedly connected to the upper end of the two round rods (601). The support plate (603) is fixedly connected to the mounting frame (701), and a spring (602) is sleeved on the round rod (601). The two ends of the spring (602) abut against the horizontal plate (5) and the support plate (603) respectively. A protective cap (605) is fixedly connected to the lower end of the round rod (601). A damping ring (606) is provided between the protective cap (605) and the horizontal plate (5). A first switch (607) and a second switch (608) are respectively installed on the upper surface of the horizontal plate (5). A toggle block (604) is fixed on the lower surface of the support plate (603) corresponding to the first switch (607) and the second switch (608). The first switch (607) is connected in series with the first motor (15).

5. The anti-fall device for elderly people going up and down stairs according to claim 4, characterized in that: An alarm (10) is installed on one side of the horizontal plate (5). The alarm (10) is connected in series with the second switch (608). The alarm (10) is a buzzer.

6. The anti-fall device for elderly people going up and down stairs according to claim 1, characterized in that: A soft pad (706) is fixedly connected to the inner wall of the restraint plate (705). A slider (709) is slidably connected to the limiting plate (708) fixed on the upper surface of the mounting frame (701). A double-sided rack (707) is fixedly connected to the slider (709), and the double-sided rack (707) meshes with two irregular gears (703).

7. The anti-fall device for elderly people going up and down stairs according to claim 6, characterized in that: The inner side of the mounting frame (701) is equipped with a second electric push rod (7011), and the end of the output shaft of the second electric push rod (7011) is fixedly connected to a traction frame (7010), which is connected and fixed to a double-sided rack (707).

8. The anti-fall device for elderly people going up and down stairs according to claim 1, characterized in that: The horizontal plate (5) has two symmetrically distributed sliding grooves (9), and each of the two sliding grooves (9) is provided with a support component (8). The support component (8) includes a sleeve (801) slidably connected to the sliding groove (9) and a telescopic plate (802) slidably connected to the sleeve (801). A base plate (804) is fixedly connected to a support frame (803) provided on the top of the telescopic plate (802). A handle (805) and a protective pad (806) are respectively provided on the upper surface of the base plate (804).

9. A fall prevention device for the elderly going up and down stairs according to claim 8, characterized in that: A locking rod (807) is threadedly connected to a screw hole on one side of the sleeve (801). The locking rod (807) is a screw, and a locking groove is provided on one side of the telescopic plate (802).

10. A fall prevention device for the elderly going up and down stairs according to claim 8, characterized in that: A telescopic control mechanism (17) is installed on one side of the horizontal plate (5). The telescopic control mechanism (17) includes a protective frame (1701) installed on one side of the horizontal plate (5) and a bidirectional lead screw (1704) rotatably connected to the protective frame (1701). Two symmetrically distributed slides (1705) are threaded onto the bidirectional lead screw (1704). A traction member (1703) is fixedly connected to one side of the slide (1705). The traction member (1703) is connected and fixedly connected to the corresponding sleeve (801). A limit rod (1702) is fixedly connected to the protective frame (1701). A limit hole adapted to the limit rod (1702) is opened on the slide (1705) at the corresponding limit rod (1702). A second motor (1706) for controlling the rotation of the bidirectional lead screw (1704) is installed on one side of the protective frame (1701).

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