Four-wheel chassis and anti-collision strip of unmanned floor cleaning vehicle

Abstract

The utility model relates to vehicle accessory technical field, and disclose a four-wheel drive chassis and crash strip of unmanned sweeper, the four-wheel drive chassis and crash strip of unmanned sweeper, including chassis body, be provided with protection subassembly on the chassis body. The four-wheel drive chassis and crash strip of unmanned sweeper, through setting protection subassembly, cooperation refitting interface can improve adaptability, cooperation charging copper sheet, charging port and power supply realize diversified charging, cooperation field control starting drive motor, make the suspension can level steering, cooperation suspension rod and shock absorber can better shock attenuation, cooperation integrated servo wheel hub motor and wheel hub body make the wheel rotation, cooperation first clamping block, main groove, main frame, side frame, second clamping block, secondary groove and cross -bracing, when the safety touch edge sensor installed horizontally first contacts the obstacle, and then sends the signal to field control, and field control controls integrated servo wheel hub motor, cuts off power source, immediately stops the movement of vehicle, thereby plays the protection function.

Description

Technical Field

[0001] This utility model relates to the field of vehicle parts technology, specifically to a four-wheel drive chassis and anti-collision strips for an unmanned floor scrubber. Background Technology

[0002] With the rapid development of automated cleaning technology, driverless floor scrubbers have been widely used in large public areas such as shopping malls, airports, and industrial parks due to their advantages such as no need for human supervision, high cleaning efficiency, and precise operation paths. As the core load-bearing and driving component of driverless floor scrubbers, the four-wheel drive chassis directly determines the vehicle's mobility, load capacity, and driving stability.

[0003] Currently, the industry's technological research and development of unmanned floor scrubbers focuses on optimizing the power output of the chassis drive system, improving the responsiveness of protective components, and expanding the adaptability of functional modules, in order to meet the "efficient, safe, and multifunctional" usage requirements of cleaning equipment in different scenarios and promote the development of automated cleaning equipment towards a more intelligent and reliable direction.

[0004] However, the existing four-wheel drive chassis and anti-collision strips of unmanned floor scrubbers still have certain shortcomings in practical applications. On the one hand, some floor scrubber chassis adopt a two-wheel drive structure, which is prone to wheel slippage on wet and slippery surfaces or under heavy loads (such as when fully loaded with water and detergent), resulting in poor driving stability and insufficient steering flexibility, making it difficult to turn around on the spot or move laterally accurately, increasing the difficulty of operation in narrow areas. At the same time, the charging methods of existing chassis are relatively simple, mostly relying on traditional charging ports for manual plugging and unplugging of chargers. In large-area cleaning scenarios, frequent bending over to plug and unplug chargers is not only time-consuming and laborious, but also reduces the continuous operation efficiency of the equipment. On the other hand, existing anti-collision strips mostly adopt a single metal frame structure, lacking accurate collision detection and rapid braking linkage mechanisms, and lacking anti-collision strip structures that are easy to install, so the overall safety and practicality need to be improved.

[0005] In view of this, we propose a four-wheel drive chassis and anti-collision strips for an unmanned floor scrubber. Utility Model Content

[0006] The purpose of this invention is to provide a four-wheel drive chassis and anti-collision strips for an unmanned floor scrubber, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, this utility model provides the following technical solution: A four-wheel drive chassis and anti-collision strip for an unmanned floor scrubbing vehicle, comprising a chassis body, a control knob and a start / stop button on the chassis body, wheels on the exterior of the chassis body, and a protective component on the chassis body, the protective component including: The chassis body is equipped with a LiDAR, which is fixedly installed at both the front and rear ends. A modification interface is fixedly installed at the top of the chassis body. Charging copper plates and charging ports are provided on the chassis body. Both charging copper plates and charging ports are electrically connected to a power supply. A domain controller is fixedly installed inside the chassis body. The floor scrubber is driven by a driving structure, which includes a drive motor. The drive motor is fixedly mounted on the chassis body. A suspension is fixedly mounted on the output end of the drive motor. One end of a suspension rod is hinged to the suspension, and the other end of the suspension rod is hinged to an integrated servo hub motor. A shock absorber is provided between the suspension and the integrated servo hub motor. The stator of the integrated servo hub motor is fixedly connected to the hub body, and the rotor of the integrated servo hub motor is fixedly connected to the wheel. The anti-collision strip body is used to protect the chassis body from impacts by foreign objects. The anti-collision strip body includes a main frame, which is fixedly installed at the bottom of the chassis body. A main groove is opened on the main frame. A side frame is welded to the main frame. A cross frame is welded to the side frame. A secondary groove is opened on the cross frame. A first locking block and a second locking block are respectively provided at both ends of the side frame. The first locking block engages with the main groove, and the second locking block engages with the secondary groove. A safety contact edge sensor is fixedly installed on the cross frame.

[0008] In a further embodiment, four sets of wheels and driving structures are provided, each located at one of the four corners of the chassis body, allowing the floor scrubber to move more easily.

[0009] In a further embodiment, the anti-collision strip body is provided in two sets, which are respectively located at the front and rear ends of the chassis body for better protection.

[0010] In a further embodiment, two side frames are provided within the body of a single anti-collision strip, and the two side frames are mirror images of each other at both ends of the main frame, making it more robust.

[0011] In a further embodiment, the chassis body is also provided with auxiliary components, the auxiliary components including mounting brackets, which are fixedly installed on the top of the chassis body, and two sets of mounting brackets are provided.

[0012] In a further embodiment, a plastic component is fixedly installed on the charging port, and a protective sleeve is fixedly installed on the plastic component. The protective sleeve is fitted over the outside of the charging port to better prevent dust and water damage.

[0013] In a further embodiment, an asynchronous motor is fixedly mounted on the chassis body, and a protective cover is fixedly mounted on the output shaft of the asynchronous motor. The protective cover is located outside the charging copper sheet for better dust and water protection.

[0014] Compared with the prior art, this utility model provides a four-wheel drive chassis and anti-collision strips for an unmanned floor scrubber, which has the following beneficial effects: 1. The four-wheel drive chassis and anti-collision strips of this unmanned floor scrubber are designed to improve overall safety. Protective components, combined with a lidar sensor on the chassis, allow for better movement of the scrubber. Pre-installed modification interfaces enhance adaptability. Charging copper plates, charging ports, and power supplies enable diverse charging methods. The charging copper plates conduct electricity upon contact with the base station's copper plates, and power is supplied via rear wiring, reducing the time spent bending over to plug and unplug chargers. The domain controller-activated drive motor enables horizontal steering of the suspension. The suspension rods and shock absorbers provide better shock absorption. An integrated servo hub motor and hub body rotate the wheels, engaging the first locking block into the main slot for easy welding of the main frame and side frame. A second locking block into the secondary slot facilitates welding of the cross frame and side frame. When the chassis encounters obstacles such as rocks during forward or reverse movement, the laterally mounted safety edge sensor first contacts the obstacle, transmitting a signal to the domain controller. The domain controller then controls the integrated servo hub motor to cut off the power source and immediately stop the vehicle's movement, thus providing protection.

[0015] 2. To improve the overall practicality of the driverless floor scrubber's four-wheel drive chassis and anti-collision strips, auxiliary components are set up to better install other car wash-related equipment with the mounting bracket. Plastic parts and protective covers are used to better cover and protect the charging port when not in use, preventing dust and water from entering. When the asynchronous motor is started, the protective cover can rotate, thereby protecting the charging copper plate when not in use from dust and water. At the same time, opening the protective cover does not affect the docking and charging, thus improving the overall practicality. Attached Figure Description

[0016] Figure 1 This is a first-view schematic diagram of the overall structure of this utility model; Figure 2 This is a second-view schematic diagram of the overall structure of this utility model; Figure 3 This utility model Figure 2 Enlarged structural diagram of region A in the middle; Figure 4 This is a third-view schematic diagram of the overall structure of this utility model; Figure 5 This utility model Figure 4 Enlarged structural diagram of region B in the middle; Figure 6 This is a schematic diagram of the connection of some parts of the structure of this utility model; Figure 7 This is an exploded view of the anti-collision strip body structure of the protective component of this utility model; Figure 8This is a first-view schematic diagram of the assembly of the anti-collision strip body of this utility model; Figure 9 This is a second-view schematic diagram of the assembly of the anti-collision strip body of this utility model; Figure 10 This is a schematic diagram of the driving structure of this utility model; Figure 11 This is a schematic diagram of the wheel and structural connection of this utility model; Figure 12 This is a first schematic diagram illustrating the anti-collision working principle of this utility model; Figure 13 This is the second schematic diagram illustrating the anti-collision working principle of this utility model.

[0017] Explanation of icon numbers: 1. Chassis body; 2. Control knob; 3. Start / stop button; 4. Wheels; 5. Protection components; 51. LiDAR; 52. Retrofit interface; 53. Charging copper plate; 54. Charging port; 55. Power supply; 56. Domain controller; 57. Drive motor; 58. Suspension; 59. Integrated servo hub motor; 510. Suspension rod; 511. Shock absorber; 512. Hub body; 513. Main frame; 514. Main slot; 515. Side frame; 516. First locking block; 517. Second locking block; 518. Cross frame; 519. Secondary slot; 520. Safety contact sensor; 6. Auxiliary components; 61. Mounting bracket; 62. Plastic parts; 63. Protective cover; 64. Asynchronous motor; 65. Protective shield. Detailed Implementation

[0018] 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.

[0019] In this application, the term "above" indicates the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. It is primarily used to better describe this application and its embodiments, and is not intended to limit the indicated device, element, or component to having a specific orientation, or to construct and operate in a specific orientation. Furthermore, the term "above" may also be used in certain circumstances to indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application according to the specific circumstances.

[0020] Please see Figures 1-13 This utility model provides a technical solution: A four-wheel drive chassis and anti-collision strip for an unmanned floor scrubber includes a chassis body 1, a control knob 2 and a start / stop button 3 on the chassis body 1, and wheels 4 on the outside of the chassis body 1.

[0021] The chassis body 1 serves as the core load-bearing structure (with a load-bearing surface of 460mm x 400mm, which is larger). Its top, bottom, and front and rear ends are pre-installed with mounting interfaces for fixing the control knob 2, start / stop button 3, wheels 4, and various functional components.

[0022] In one embodiment of this utility model, a protection component 5 is provided on the chassis body 1. The protection component 5 includes a laser radar 51. The laser radar 51 is fixedly installed at both the front and rear ends of the chassis body 1. A modification interface 52 is fixedly installed at the top of the chassis body 1. A charging copper plate 53 and a charging port 54 are provided on the chassis body 1. Both the charging copper plate 53 and the charging port 54 are electrically connected to a power supply 55. A domain controller 56 is fixedly installed inside the chassis body 1. The floor scrubber body is driven by a driving structure, which includes a drive motor 57. The drive motor 57 is fixedly installed on the chassis body 1. A suspension 58 is fixedly installed at the output end of the drive motor 57. One end of a suspension rod 510 is hingedly installed on the suspension 58. The other end of the suspension rod 510 is hingedly installed on an integrated servo hub motor 59. A shock absorber 511 is provided between the suspension 58 and the integrated servo hub motor 59. The stator of the integrated servo hub motor 59 is fixedly connected to the hub body 512, and the rotor of the integrated servo hub motor 59 is fixed. The chassis body 1 is equipped with four sets of wheels 4 and a driving structure, located at the four corners of the chassis body 1, allowing the floor scrubber to move more easily. The anti-collision strip body protects the chassis body 1 from impacts by foreign objects. The anti-collision strip body includes a main frame 513, which is fixedly installed at the bottom of the chassis body 1. A main groove 514 is formed on the main frame 513. Side frames 515 are welded to the main frame 513, and cross frames 518 are welded to the side frames 515. Secondary grooves 519 are formed on the cross frames 518. The chassis body 1 has a first locking block 516 and a second locking block 517 at both ends. The first locking block 516 engages with the main slot 514, and the second locking block 517 engages with the secondary slot 519. A safety edge sensor 520 is fixedly installed on the cross frame 518. In addition, there are two sets of anti-collision strips, which are respectively set at the front and rear ends of the chassis body 1 for better protection. Furthermore, there are two side frames 515 in each set of anti-collision strips, and the two side frames 515 are mirror images of each other at both ends of the main frame 513 for greater stability.

[0023] In this embodiment, the control knob 2 has a built-in potentiometer. When rotated, it converts the mechanical adjustment into an electrical signal, which is transmitted to the domain controller 56 in real time. The start / stop button 3 is a self-resetting switch. When pressed, it sends a start / stop trigger signal to the domain controller 56. The domain controller 56 has a built-in central processing unit, signal receiving module, and drive module. After receiving the command from the domain controller 56, the drive motor 57's rotor starts to rotate. Through a reducer (built-in, not labeled), the speed is reduced and the torque is increased, driving the connection between the output shaft and the suspension 58 to rotate. This allows the suspension 58 to achieve horizontal steering around a fixed hinge point (the steering angle range is set by the domain controller 56 according to the adjustment signal of the control knob 2; clockwise rotation of the control knob 2 corresponds to right steering, and counterclockwise rotation corresponds to left steering). (The larger the angle, the greater the steering range). While the suspension 58 is steering, the integrated servo hub motor 59 receives the drive command from the domain controller 56. The motor stator generates a rotating magnetic field, which drives the rotor to rotate. The suspension rod 510 between the suspension 58 and the integrated servo hub motor 59 is connected by a ball joint hinge, which can adaptively rotate with the up and down movement of the wheel 4. At the same time, the shock absorber 511 absorbs the vibration energy generated by road bumps and prevents the vibration from being transmitted to the chassis body 1. The rotor of the integrated servo hub motor 59 is fixedly connected to the wheel 4 by a spline. The rotation of the rotor directly drives the rotation of the wheel 4. The four sets of wheels 4 achieve different speeds according to the command of the domain controller 56 to complete four-wheel drive movement and steering actions, enabling the vehicle to turn around on the spot and travel in a straight line in all directions.

[0024] The lidar 51 (laser rangefinder) at both ends of the chassis body 1 emits laser beams in real time. After the laser beams come into contact with obstacles, they are reflected back to the radar receiving module. The lidar 51 converts the distance and position information of the obstacle into electrical signals and sends the data to the domain controller 56 every 100ms. After receiving the environmental data from the lidar 51, the domain controller 56 compares it with the preset driving path (such as the clean area planning path). If an obstacle is detected ahead (the distance is less than the safety threshold, such as 50cm), the drive command sent to the integrated servo hub motor 59 is immediately adjusted to reduce the vehicle speed or change the steering direction to avoid collision and ensure the accuracy of movement.

[0025] The main frame 513 is pre-welded to the bottom of the chassis body 1. Main slots 514 (width matching the first locking block 516) are respectively opened at both ends of the main frame 513. A first locking block 516 (rectangular protrusion, size matching the clearance of the main slot 514) is welded to one end of the side frame 515. During installation, the first locking block 516 is aligned with the main slot 514 and inserted to achieve precise positioning of the main frame 513 and the side frame 515, followed by welding. Secondary slots 519 (length matching the width of the chassis body 1) are respectively opened at both ends of the cross frame 518. The second locking block 517 is inserted into the secondary slot 519 to complete the positioning of the cross frame 518 and the side frame 515. They are then welded and fixed in place. The safety edge sensor 520 (strip-shaped, with a length matching the cross frame 518) is bolted to the cross frame 518, with the sensor trigger surface facing the outside of the chassis body 1 to ensure priority contact with obstacles. When the floor scrubber moves forward or backward, if obstacles such as rocks or steps appear in front of or behind the chassis body 1, the safety edge sensor 520 (pressure-sensitive) on the cross frame 518 will activate. Upon contact with an obstacle, the conductive rubber inside the sensor deforms under pressure, causing the two-pole contacts to conduct, generating a collision trigger signal (the signal voltage changes from 5V to 0V). The trigger signal from the safety edge sensor 520 is transmitted in real time to the domain controller 56 via a shielded wire. After the signal receiving module of the domain controller 56 recognizes the signal, it determines it as the highest priority command (prioritizing movement and steering commands) and immediately initiates the emergency braking procedure. The domain controller 56 simultaneously sends a power-off command to the four integrated servo hub motors 59, and the integrated servo hub motors 59 immediately stop rotating. At the same time, the domain controller 56 sends a stop command to the drive motor 57, and the drive motor 57 stops operating. To prevent damage to the chassis body 1, wheels 4, and integrated servo hub motors 59 due to the collision, after the vehicle stops, the indicator light on the start / stop button 3 flashes (red) and a fault signal is sent to the control terminal (such as a remote control console, not labeled) to prompt the operator to handle the obstacle. After the obstacle is cleared, pressing the start / stop button 3 releases the braking state and restores normal operation.

[0026] Power supply 55 is connected to electrical components such as domain controller 56, drive motor 57, and integrated servo hub motor 59 via wires. Power supply 55 has a built-in power sensor that transmits power data to domain controller 56 in real time. Current is transmitted to the charging management module of power supply 55 through the wire at the rear of charging copper plate 53 to start charging. The modification interface 52 (standardized interface, such as USB Type-C or industrial Ethernet interface) at the top of chassis body 1 is connected to domain controller 56 via wires, which can connect to car wash related equipment such as cleaning brushes and spray devices. Domain controller 56 sends control commands (such as cleaning brush speed adjustment) to external devices through modification interface 52, and at the same time receives status feedback signals from external devices, improving the functional adaptability of chassis body 1 and meeting the needs of different cleaning scenarios.

[0027] In one embodiment of this utility model, an auxiliary component 6 is also provided on the chassis body 1. The auxiliary component 6 includes a mounting bracket 61, which is fixedly installed on the top of the chassis body 1. Two sets of mounting brackets 61 are provided. In addition, a plastic part 62 is fixedly installed on the charging port 54, and a protective cover 63 is fixedly installed on the plastic part 62. The protective cover 63 is fitted outside the charging port 54 to better prevent dust and water. In addition, an asynchronous motor 64 is fixedly installed on the chassis body 1, and a protective cover 65 is fixedly installed on the output shaft of the asynchronous motor 64. The protective cover 65 is located outside the charging copper sheet 53 to better prevent dust and water.

[0028] In this embodiment, auxiliary equipment related to car washing (such as the roller brush motor and water tank, not labeled) is fixed to the oblong holes of the mounting bracket 61 with bolts. When charging is required through the charging port 54, the operator opens the protective cover 63 (the plastic part 62 is made of elastic material, which can be bent for easy opening) outside the charging port 54, inserts the charger plug into the charging port 54, and the metal contacts inside the charging port 54 contact the plug. The current is transmitted to the charging management module of the power supply 55 through the wires of the charging port 54 to start charging. When charging is done using the base station, the floor washing vehicle drives to the designated position of the base station, and the charging copper plate 53 (copper alloy material, gold-plated surface for anti-oxidation) on the chassis body 1 contacts and collides with the copper plate of the base station. The two are tightly attached to achieve conductivity. When the charging port 54 is not in use, the protective cover 63 is tightly fitted to the outside of the charging port 54 by the tension of the plastic part 62 to prevent dust and water stains from entering the inside of the charging port 54. When the charging port 54 needs to be used, the operator pulls the protective cover 63 outward, and the plastic part 62 releases its tension. The protective cover 63 undergoes elastic deformation, detaching from the charging port 54. After charging is complete, the protective cover 63 is released, and the plastic part 62 returns to its original shape, causing the protective cover 63 to automatically reset and re-seal. When the charging copper plate 53 is not in use, a forward rotation command is sent to the asynchronous motor 64. The output shaft of the asynchronous motor 64 drives the protective cover 65 to rotate around the axis. When it rotates to the position covering the charging copper plate 53, dust and water protection is achieved, while avoiding hard contact between the protective cover 65 and the charging copper plate 53, which could cause wear. When the charging copper plate 53 needs to be used for charging, the domain controller 56 receives the charging command and sends a reverse rotation command to the asynchronous motor 64. The asynchronous motor 64 drives the protective cover 65 to rotate in the opposite direction, ensuring that the connection between the charging copper plate 53 and the base station copper plate is not blocked. After charging is complete, the domain controller 56 sends a forward rotation command to the asynchronous motor 64, and the protective cover 65 covers the charging copper plate 53 again, restoring the protective state. The asynchronous motor 64 has a built-in position sensor that can feed back the rotation position signal of the protective cover 65 to the domain controller 56 to ensure that the protection is in place.

[0029] Among them, the control knob 2, start / stop button 3, lidar 51, modification interface 52, charging copper plate 53, charging port 54, power supply 55 (battery capacity of 27Ah), drive motor 57, integrated servo hub motor 59 (model 5.5 inch 3.5Nm), safety contact sensor 520, and asynchronous motor 64 are all electrically connected to the domain controller 56. The standard parts used in this application can all be purchased from the market. The specific connection methods of each part are all connected by conventional methods such as riveting and welding that are mature in the prior art. The standard parts are all conventional models in the prior art. In addition, the circuit connection adopts conventional connection methods in the prior art, and will not be described in detail here.

[0030] The present invention has been described in detail above. However, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, any modifications or improvements that do not depart from the spirit of the present invention are within the protection scope of the present invention.

Claims

1. A four-wheel drive chassis for an unmanned floor scrubbing vehicle, comprising a chassis body (1), wherein a control knob (2) and a start / stop button (3) are provided on the chassis body (1), and wheels (4) are also provided on the outside of the chassis body (1), characterized in that: The chassis body (1) is provided with a protective component (5), the protective component (5) including: The chassis body (1) is equipped with a laser radar (51) at both the front and rear ends. The chassis body (1) is equipped with a modification interface (52) at the top. The chassis body (1) is provided with a charging copper plate (53) and a charging port (54). The charging copper plate (53) and the charging port (54) are electrically connected to the power supply (55). The chassis body (1) is equipped with a domain controller (56). The driving structure of the floor scrubber is driven by the driving structure, which includes a drive motor (57). The drive motor (57) is fixedly mounted on the chassis body (1). A suspension (58) is fixedly mounted on the output end of the drive motor (57). One end of a suspension rod (510) is hinged on the suspension (58). The other end of the suspension rod (510) is hinged on the integrated servo hub motor (59). A shock absorber (511) is provided between the suspension (58) and the integrated servo hub motor (59). The stator of the integrated servo hub motor (59) is fixedly connected to the hub body (512), and the rotor of the integrated servo hub motor (59) is fixedly connected to the wheel (4).

2. The four-wheel drive chassis of the unmanned floor scrubbing vehicle according to claim 1, characterized in that: The wheels (4) and the driving structure are provided in four sets, and are respectively located at the four corners of the chassis body (1).

3. The four-wheel drive chassis of the unmanned floor scrubber according to claim 1, characterized in that: The chassis body (1) is also provided with an auxiliary component (6), which includes a mounting bracket (61). The mounting bracket (61) is fixedly installed on the top of the chassis body (1), and there are two sets of mounting brackets (61).

4. The four-wheel drive chassis of the unmanned floor scrubber according to claim 1, characterized in that: A plastic part (62) is fixedly installed on the charging port (54), and a protective sleeve (63) is fixedly installed on the plastic part (62). The protective sleeve (63) is fitted over the outside of the charging port (54).

5. The four-wheel drive chassis of the unmanned floor scrubber according to claim 1, characterized in that: An asynchronous motor (64) is fixedly installed on the chassis body (1), and a protective cover (65) is fixedly installed on the output shaft of the asynchronous motor (64). The protective cover (65) is located outside the charging copper sheet (53).

6. A protective strip for the four-wheel drive chassis of the unmanned floor scrubber according to any one of claims 1-5, characterized in that: The system includes a crash bar body, which is used to protect the chassis body (1) from impact by foreign objects. The crash bar body includes a main frame (513), which is fixedly installed at the bottom of the chassis body (1). A main groove (514) is provided on the main frame (513). A side frame (515) is welded on the main frame (513). A cross frame (518) is welded on the side frame (515). A secondary groove (519) is provided on the cross frame (518). A first locking block (516) and a second locking block (517) are respectively provided at both ends of the side frame (515). The first locking block (516) engages with the main groove (514), and the second locking block (517) engages with the secondary groove (519). A safety edge sensor (520) is fixedly installed on the cross frame (518). The crash bar body is provided in two sets, which are respectively located at the front and rear ends of the chassis body (1).

7. The anti-collision strip according to claim 6, characterized in that: Two side frames (515) are provided in the body of the single anti-collision strip, and the two side frames (515) are mirror images of each other at both ends of the main frame (513).

Images