阅读说明：本技术 升降车体，车轮、履带复合式爬楼车 (Lifting vehicle body, wheel and crawler combined stair climbing vehicle ) 是由 刘闯 于 2019-08-23 设计创作，主要内容包括：升降车体,车轮、履带复合式爬楼车,属于爬楼车的一种。由于现有爬楼车存在载重量小、操作人员体力消耗大、安全性不高等这些问题。本发明的技术解决方案是：由全负载式、高通过性、低磨损履带式行走装置组成的底盘,用来在楼梯上行驶；在车体的适当位置设置升降系统,用来升降车体实现车轮、履带的切换和辅助履带攀爬楼梯；在升降系统的底端安装脚轮,用来在路面或者楼梯平台上行驶；货架可水平移动,将货物的重心前移,提高车辆在楼梯上行驶的安全性；车体尾部设置有双独立可收放式安全尾,进一步提高车辆的安全性,防止车辆翻覆。本发明可以实现大载重量、大体积货物在楼梯上的安全运输。(A lifting vehicle body, wheels and crawler combined type stair climbing vehicle belongs to one of stair climbing vehicles. The existing stair climbing vehicle has the problems of small carrying capacity, large physical consumption of operators, low safety and the like. The technical solution of the invention is as follows: the chassis consists of a full-load type, high-trafficability and low-abrasion crawler-type traveling device and is used for traveling on stairs; a lifting system is arranged at a proper position of the vehicle body and is used for lifting the vehicle body to realize the switching of wheels and tracks and assist the tracks to climb stairs; the bottom end of the lifting system is provided with a caster which is used for driving on a road surface or a stair platform; the goods shelf can move horizontally, so that the gravity center of the goods is moved forwards, and the safety of the vehicle running on the stairs is improved; the tail part of the vehicle body is provided with double independent retractable safety tails, so that the safety of the vehicle is further improved, and the vehicle is prevented from being overturned. The invention can realize the safe transportation of large-load and large-volume goods on stairs.)

1. The utility model provides a lift automobile body, wheel, track combined type stair climbing vehicle, includes crawler-type chassis system, operating system, but horizontal migration goods shelves system, safety tail system, handrail frame system, characterized by: the crawler-type chassis system consists of a full-load type, high-trafficability and low-abrasion crawler-type traveling device, a front base beam, a rear base beam and four connecting frames, namely a front left connecting frame, a front right connecting frame, a rear left connecting frame and a rear right connecting frame; the lifting system consists of a telescopic outer pipe, a telescopic inner pipe, a connecting plate, a trundle, a telescopic action mechanism and a mounting bracket thereof; the horizontally movable goods shelf system consists of goods shelves, a C-shaped track, a pulley block, a push-pull action mechanism and a mounting bracket thereof; the safety tail system consists of a U-shaped connecting frame, a safety tail strength pipe, a rubber anti-slip strip, a retraction action mechanism and a mounting bracket thereof.

2. The method as recited in claim 1, wherein: the front-stage left lifting system and the front-stage right lifting system are respectively fixed with a left longitudinal beam and a right longitudinal beam of the goods shelf.

3. The method as recited in claim 1, wherein: the rear-stage left and right lifting systems are respectively fixed with the left rear connecting frame and the right rear connecting frame.

4. The method as recited in claim 1, wherein: the telescopic inner pipe of the lifting system is inserted into the cavity of the telescopic outer pipe.

5. The method as recited in claim 1, wherein: the truckle passes through the connecting plate to be installed in the bottom of flexible inner tube.

6. The method as recited in claim 1, wherein: one of the mounting brackets of the telescopic action mechanism is fixed with the caster connecting plate.

7. The method as recited in claim 1, wherein: the track of the horizontally movable shelf system is in a C shape.

8. The method as recited in claim 1, wherein: the two C-shaped rails are respectively arranged on the left front connecting frame and the left rear connecting frame on the left side of the vehicle body and the right front connecting frame and the right rear connecting frame on the right side of the vehicle body.

9. The method as recited in claim 1, wherein: a middle longitudinal beam is arranged at the middle position of the longitudinal direction of the goods shelf.

10. The method as recited in claim 1, wherein: the middle longitudinal beam is positioned on the longitudinal center line of the vehicle body.

11. The method as recited in claim 1, wherein: one of the two mounting brackets of the push-pull action mechanism is mounted below the front part of the middle longitudinal beam, and the other mounting bracket is mounted in the middle of the cross beam of the rear base.

12. The method as recited in claim 1, wherein: and a layer of rubber anti-slip strip is laid on the rear surface of the safety tail strength pipe.

13. The method as recited in claim 1, wherein: the U-shaped connecting frame is fixed at the lower end of the safety tail strength pipe.

14. The method as recited in claim 1, wherein: the U-shaped connecting frame is respectively connected with the left lower longitudinal frame and the right lower longitudinal frame through bolts.

15. The method as recited in claim 1, wherein: one of the mounting brackets of the retraction actuating mechanism is mounted on the front surface of the safety tail strength tube.

16. The method as recited in claim 1, wherein: the safety tail system is not additionally arranged, and the number of the rear-stage lifting system is reduced to one point, namely the two-stage three-point vehicle body (commonly known as a medium-sized vehicle body).

17. The method as recited in claim 16, wherein: the rear-stage lifting system is positioned in the middle of the rear part of the vehicle body, the top end of the telescopic outer tube is connected with the middle of the upper cross frame of the armrest frame, and the lower end of the telescopic outer tube is connected with the lower left cross frame and the lower right cross frame respectively and is positioned in the middle.

18. The method as recited in claim 1, wherein: the safety tail system and the horizontally movable goods shelf system are not additionally arranged, the goods shelf is fixedly connected with the chassis, and the lifting system is reduced into a first-stage two-point type vehicle body (generally called as a light-weight vehicle body).

19. The method as recited in claim 18, wherein: the two lifting systems are respectively positioned in the middle of the left side and the right side of the vehicle body, the top ends of the telescopic outer tubes of the two lifting systems are respectively connected with the left upper longitudinal frame and the right upper longitudinal frame, and the bottom ends of the telescopic outer tubes of the two lifting systems are respectively connected with the left lower longitudinal frame and the right lower longitudinal frame.

1. Field of the invention

The invention relates to a lifting vehicle body, a wheel and track combined type stair climbing vehicle, and belongs to a stair climbing vehicle.

2. Background of the invention

The stair climbing vehicle is mainly divided into two categories, namely unpowered and powered. The unpowered stair climbing vehicle is a hand trailer and is not described herein. The whole structure of the powered stair climbing vehicle is L-shaped, two trundles are arranged at the bottom of the L-shaped vehicle, an action mechanism and a battery which simulate the climbing of the legs of a person are arranged between the two trundles, and a goods shelf for placing goods is arranged at the position of the L-shaped vehicle. His working mode is: the operator pulls the vehicle to use the caster wheel when the vehicle runs on the road surface; when the stair is encountered, the trundles are contacted with the vertical surface of the stair, the switch of the stair climbing action mechanism is opened at the moment, the action mechanism starts to work, and after climbing a step, an operator pulls the vehicle to move along the horizontal surface of the step, so that the trundles of the vehicle are contacted with the vertical surface of the next step in a reciprocating manner. The stair climbing vehicle has the following disadvantages: 1. the load capacity is small, and the load capacity cannot be influenced by some goods with larger volume and heavier weight. 2. The physical effort of the operator is great because the weight of the vehicle and cargo is partially applied to the operator. 3. The operator needs to control the center of gravity of the vehicle or the vehicle may overturn. 4. The potential safety hazard is great when going downstairs, because the goods shelters from the sight when going downstairs, the vehicle need go to the specific position in step turning moreover, can accomplish the action of going downstairs smoothly, will cause the vehicle to rush down stair a little carelessly. 5. The height requirement for the step is severe. After the height of the step exceeds the height of the motion of the action mechanism, the vehicle is difficult to run. 6. The running track of the vehicle on the stairs is wavy, which inevitably results in high energy consumption, not smooth running and poor continuous working capacity.

3. Summary of the invention

In order to solve the obvious defects of small vehicle-mounted weight, large physical consumption of operators, low safety of going downstairs, unstable running and the like of the conventional stair climbing vehicle, the invention provides a set of technical solution, so that the defects of the conventional stair climbing vehicle can be effectively overcome.

The technical solution of the invention is as follows: the full-load type, high-throughput and low-abrasion crawler-type traveling device (remarks: the independent patent of invention, application number or patent number: 201811569330.7, the crawler is very suitable for traveling on stairs, and is not detailed here, and is hereinafter referred to as the crawler) is connected with a base and a connecting frame to form a chassis system for traveling on the stairs; the lifting system comprises retractable castors for travelling on a road or a landing; a lifting system is arranged at a proper position of the vehicle body and used for lifting the vehicle body to realize the switching of wheels and tracks and assist the tracks to climb stairs; the goods shelf on the vehicle body can move forwards horizontally, so that the gravity center of goods moves forwards, and the safety of the vehicle running on stairs is improved; retractable double independent safety tails are arranged on the left side and the right side of the tail of the vehicle body, and the safety tails are put down when the vehicle runs on stairs, so that the running safety of the vehicle on the stairs is further improved, and the vehicle is prevented from being overturned.

The working mode of the invention is as follows: when the vehicle runs on a road surface or a plane, the lifting system extends out of the trundles to lift the vehicle body, the track is lifted off the ground, the trundles are in contact with the ground, and an operator pushes the vehicle to run; when the vehicle needs to climb stairs, the vehicle can be pushed to the side of the stairs, the lifting system is operated to lift the vehicle body to a certain height in a horizontal state (remarks: the lower plane of the crawler is enabled to exceed the tread height of a third-stage step, usually the lifting height is set to be 50-55 cm, so that the use requirement can be met when facing most of the stairs), because the front-stage lifting system is reserved with a certain effective suspension distance from the front end of the vehicle body (remarks: assuming that the shelf system is in a reset state, when the caster is parallel to the crawler, the point of the front wheel surface, which is vertical to the edge line of the crawler, is set to be A, the starting point of the straight line part of the edge line of the front crawler is set to be B, the shortest distance from the point B to the point A is effectively called as the suspension distance, represented by letters as BA, the step depth of the stairs is set, the difficulty of climbing stairs is influenced by factors such as the step height of the steps, the step depth, the inclination angle of the stairs, the length and the width of the vehicle body, the height of a crawler belt and the like; according to the field investigation of the resident area stairs, the general conditions are as follows: the step height is less than or equal to 18cm, the step depth is less than or equal to 25cm, and the stair inclination angle is less than or equal to 36 degrees; because the space at the landing is limited, the length of the car body is usually set to be less than or equal to 120cm and the width of the car body is set to be less than or equal to 75cm in order to facilitate the turning around of the car at the turning place; because the track is designed to be as low and short as possible and the height is strictly controlled in order to reduce the gravity center and increase the safety when the vehicle runs on the stairs, the climbing difficulty of the first, second and third steps is the highest for the crawler vehicle in view of combining all factors, so when the vehicle runs from a plane to the stairs, the first third step is not feasible if only the track is used for climbing, and the aim of lifting the vehicle body is designed: firstly, can realize the switching of wheel and track, secondly tertiary step before supplementary track climbing, so only need operation operating system with vehicle lifting take the altitude, make the plane be higher than the vertical height of preceding tertiary step under the track, then with the automobile body forward impel the track be in as far as directly over the tertiary step, withdraw the truckle this moment, the track will fall on the tertiary step, operating system just can assist the step that tertiary is difficult to the climbing before the track climbing. When the step tread depth is less than or equal to 25cm, the car body length is less than or equal to 120cm, and the car body width is less than or equal to 75cm, the effective suspension distance is usually set to be 45-50 cm, the setting of the parameter can meet the requirement that when a vehicle climbs most of stairs, the lifting system can assist the crawler to climb the front three steps through one lifting action, if the lifting system meets special conditions, the lifting system can possibly need to perform the second lifting action, the aim is to enable the inclination angle of the car body to be close to that of the stairs as far as possible, and the difficulty of the crawler in climbing the next step is reduced. The installation position of the rear-stage lifting system has no requirement on effective suspension distance, and is close to the rear part of the vehicle body as far as possible only under the condition that a safety tail system installation space is reserved. ) When the vehicle body is lifted, the crawler belt is in a suspended state, the vehicle is pushed forwards towards the stairs to enable the lower plane of the crawler belt to be located right above the third-stage step, the lifting system retracts the trundles to enable the crawler belt to be in contact with the stairs, the goods shelf is moved forwards, the safety tail is put down, and the vehicle is operated to run by using the crawler belt; when the vehicle runs to the joint of the stair and the stair platform, the goods shelf is recycled, the vehicle continues to run forwards, when the corner of the last step reaches the position close to the center of the crawler belt, the lifting systems on the left side and the right side of the front stage extend out at the moment, but the truckles are not in contact with the stair plane, the goods shelf is moved forwards to press the vehicle body downwards by using the weight of goods, the truckles are recycled when the truckles are in contact with the ground, the vehicle integrally returns to the horizontal state, the goods shelf is recycled when the vehicle runs to ensure that the vehicle cannot turn backwards, and the safety tail is recycled, so that the purpose of preventing the vehicle from smashing towards the stair plane when the vehicle runs to the critical point of the. The vehicle is in a state of going upstairs or downstairs on stairs, and is in a forward state when going upstairs and in a backward state when going downstairs. When a user goes down a stair from a stair platform to the stair, the safety tail needs to be put down firstly, then the goods shelf extends out, when the vehicle goes to the position near the center of the crawler track at the corner of the platform step, the rear-stage lifting system extends out to the position where the trundles contact with the stair, the goods shelf is retracted at the moment, the vehicle body is pressed down by using the weight of goods, the rear-stage lifting system is retracted at the moment, and along with the slow retraction of the rear-stage lifting system, the vehicle body is slowly converted into an inclined state which is the same as the inclined angle of the stair from a horizontal state (note: when the vehicle goes down the stair, the vehicle needs to be converted into the inclined state which is the same as the inclined angle of the stair from the horizontal state, the conversion modes are one mode, the other mode is that the safety tail is put down firstly, then the goods shelf extends out, when the vehicle goes to the position near the center, the front part of the vehicle body is lifted by the lifting force of the front stage lifting system, the crawler is operated to run at the moment, and when the gravity center of the vehicle passes over the corner of the stair platform and the vehicle body can be kept in an inclined state by the weight of the vehicle, the front stage lifting system is retracted. ) When the crawler belt is completely contacted with the stairs, the crawler belt stretches out of the goods shelf and goes downstairs by utilizing the crawler belt; when the vehicle runs to the stair platform, the safety tail is firstly contacted with the stair plane, the safety tail can be retracted at the moment, the vehicle can continue running by the crawler, when the vehicle runs to the position where the caster extending out of the front-stage lifting system can contact with the stair plane, the goods shelf is retracted at the moment, the front-stage lifting system and the rear-stage lifting system extend out, the vehicle body is adjusted to be in a horizontal state from an inclined state by the aid of the lifting system, and the caster is used for running and turning on the stair platform. The number and position of the vehicle lifting systems are different and the configuration of the safety systems are different according to the volume and weight of the loaded goods, and therefore three vehicle body structures are developed, namely: (1) first-level two-point vehicle body (commonly known as light vehicle body). The vehicle body is simple and light in structure, the lifting system is positioned in the middle of the left side and the right side of the vehicle body and is connected with the goods shelf, and because the carried goods are light and small articles, an operator can completely control the vehicle, so that two safety configurations of the goods shelf, namely horizontal movement and safety tail, are cancelled. (2) And a two-stage three-point vehicle body (commonly known as a medium-sized vehicle body). The two-stage lifting system is divided into a front stage and a rear stage, and the three-stage lifting system is characterized in that the front stage lifting system is provided with two lifting point positions which are respectively positioned at the left side and the right side of the goods shelf, connected with the goods shelf and move together with the goods shelf; the rear-stage lifting system only has one lifting point position located in the middle of the rear part of the vehicle body. The safety arrangement provides a horizontally movable shelf. (3) And a two-stage four-point vehicle body (commonly known as heavy). The two-stage lifting system is divided into a front stage and a rear stage, and the four-point lifting system is divided into four lifting point positions of the front stage and the rear stage. The front-stage lifting system is positioned at the left side and the right side of the front part of the goods shelf, is connected with the goods shelf and moves along with the goods shelf; the rear-stage lifting system is positioned at the left and right sides of the rear part of the vehicle body and is connected with the armrest frame. The safety configuration is provided with a horizontally movable goods shelf and a double independent retractable safety tail.

The invention has the beneficial effects that: (1) the vehicle can realize the transportation of large-load-capacity and large-volume goods on stairs, and has high practical value.

(2) And the running safety is high. When the vehicle is designed, the driving safety is considered seriously, a horizontally movable goods shelf is arranged on a vehicle body, when the vehicle drives on stairs, the goods shelf moves upwards to move the gravity center of goods upwards, so that the gravity centers of the vehicle and the goods are kept at the position near the center point of a track; in order to increase the safety of the vehicle, the vehicle is further provided with double independent retractable safety tails, and even if one safety tail breaks down, the other safety tail can also ensure the safety of the vehicle and prevent the vehicle from overturning.

(3) And the physical consumption of operators is small.

(4) And the modification potential is large. For example, heavy vehicles are added with the lifting height of the lifting system, so that the vehicle body can be lifted to a height higher than the bottom plate of the wagon compartment, the vehicles can directly run into the wagon compartment, direct transportation from the wagon compartment to a warehouse can be realized after goods are loaded, and even if stairs are encountered in the transportation process (for example, the warehouse is in the second floor or the third floor and the like), the transportation is not influenced. Such as a medium-sized vehicle, can be modified into a stair climbing wheelchair.

(5) The vehicle is developed into a system, covers light, medium and heavy vehicles and has wide application range.

4. Description of the drawings

FIG. 1: two-stage four-point type vehicle body structure left rear 45-degree stereoscopic view

FIG. 2: left side plan view of two-stage four-point vehicle body structure

FIG. 3: 'C' -shaped rail rear side view

FIG. 4: left side plan view of pulley block

FIG. 5: left side plan view of shelf horizontal moving mechanism

FIG. 6: left side plan view of an elevator system

FIG. 7: rear side plan view of safety tail

FIG. 8: left side plan view of safety tail

FIG. 9: two-stage three-point type vehicle body structure left rear 45-degree stereoscopic view

FIG. 10: left-rear 45-degree stereoscopic view of primary two-point type vehicle body structure

5. Detailed description of the preferred embodiments

Example 1: two-stage four-point vehicle body (popular name: heavy type)

The implementation mode is as follows: as shown in fig. 1, a left front connecting frame (4) and a right front connecting frame (5) are respectively welded on the left side and the right side of a front base cross beam (2), a left rear connecting frame (6) and a right rear connecting frame (7) are respectively welded on the left side and the right side of a rear base cross beam (3), and the four connecting frames need to be higher than the upper surface of a track (as shown in fig. 2) and extend out for a certain distance to the left side and the right side. Welding a C-shaped track (8) on a left front connecting frame (4) and a left rear connecting frame (6) (shown in figure 2), welding the other C-shaped track on a right front connecting frame (5) and a right rear connecting frame (7), keeping the two C-shaped tracks (8) at a proper distance and symmetrical to the longitudinal center line of the vehicle body, and respectively placing two pulley blocks (9) in each C-shaped track (8) (shown in figures 3 and 4); welding a left longitudinal beam (10), a right longitudinal beam (12), a front cross beam (13) and a rear cross beam (15) together to form a rectangular frame, welding a middle longitudinal beam (11) at the longitudinal middle position, positioning the middle longitudinal beam on the longitudinal central line of a vehicle body, welding two middle cross beams (14) at the proper position at the front part for enhancing the structural strength of the goods shelf, respectively connecting two pulley blocks (9) at the front part with the proper positions at the left and right sides of the middle cross beam (14) of the goods shelf, respectively connecting two pulley blocks (9) at the rear part with the proper positions at the left and right sides of the rear cross beam (15) of the goods shelf, welding a goods shelf push-pull action mechanism mounting bracket (17) below the proper position at the front part of the middle longitudinal beam (11), welding another goods shelf push-pull action mechanism mounting bracket (17) at the middle part of the rear base cross beam (3), and connecting the bottom end of the goods shelf push-pull action mechanism (, the front end of the shelf push-pull action mechanism mounting bracket (17) at the lower part of the middle longitudinal beam (11) is connected with the middle longitudinal beam through a bolt (as shown in figure 5), when the shelf push-pull action mechanism (16) is pushed out, the shelf can drive the pulley block (9) to horizontally move forwards along the C-shaped track (8), and when the shelf is pulled back, the shelf can horizontally move backwards.

As shown in fig. 6, the elevator system component comprises: the telescopic outer pipe (30), the telescopic inner pipe (31), the telescopic action mechanism (32), the telescopic action mechanism mounting bracket (33), the caster (34), the caster connecting plate (35) and the connecting bolt (36). The implementation mode is as follows: the telescopic inner tube (31) and the telescopic action mechanism mounting bracket (33) are respectively welded with a proper position of a caster connecting plate (35), the other telescopic action mechanism mounting bracket (33) is welded at a proper position of the upper part of the telescopic outer tube (30), the telescopic inner tube (31) is inserted into a cavity of the telescopic outer tube (30), the head and the tail of the telescopic action mechanism (32) are respectively connected with the telescopic action mechanism mounting bracket (33) on the lower part and the upper part through bolts, and the caster (34) and the caster connecting plate (35) are fixed through connecting bolts (36). When the lifting system is required to be arranged at the proper position of the vehicle body, the telescopic outer pipe (30) is only required to be welded at the proper position of the vehicle body, and the structural strength of the telescopic outer pipe is enhanced through the support. When the telescopic action mechanism (32) extends out, the telescopic inner pipe (31) is driven to extend out of the telescopic outer pipe (30), the caster (34) is pushed out and is contacted with the ground, and the vehicle body is lifted.

As shown in fig. 1 and 2, a left front lifting system (26) is arranged at the front part of a left longitudinal beam (10) of the goods shelf (remarks: an effective suspension distance needs to be reserved), a telescopic outer tube (30) and the left longitudinal beam (10) of the goods shelf are welded and fixed, and two ends of a reinforcing bracket (44) of the left front lifting system are respectively welded with the left longitudinal beam (10) of the goods shelf and the telescopic outer tube (30), so that the structural strength of the left front lifting system is further enhanced; a right front lifting system (27) is arranged at the front part of the right longitudinal beam (12) of the goods shelf (remark: an effective suspension distance needs to be reserved), a telescopic outer tube (30) and the right longitudinal beam (12) of the goods shelf are welded and fixed, and two ends of a reinforcing bracket (45) of the right front lifting system are respectively welded with the right longitudinal beam (12) of the goods shelf and the telescopic outer tube (30), so that the structural strength of the right front lifting system is enhanced; the left front lifting system (26) and the right front lifting system (27) move horizontally with the goods shelf. A left rear lifting system (28) is arranged at the left end part of the left rear connecting bracket (6), the lower end of a telescopic outer pipe (30) is welded with the left end part of the left rear connecting bracket (6), the top end of the telescopic outer pipe is welded with the front part of a left upper longitudinal frame (20), the lower part of the telescopic outer pipe is welded with the front part of a left lower longitudinal frame (18), the two ends of a left middle reinforcing bracket (22) are respectively welded with the end part of a left front connecting frame (4) and the front part of the left upper longitudinal frame (20), and the two ends of a left rear reinforcing bracket (24) are respectively welded with the telescopic outer pipe (30) and the left lower longitudinal frame (18) so as to reinforce the structural strength of a handrail frame system; the right end part of the right rear connecting bracket (7) is provided with a right rear lifting system (29), the right end parts of a telescopic outer pipe (30) and the right rear connecting bracket (7) are welded, the upper part of the right rear connecting bracket is welded with the front part of an upper right longitudinal frame (21), the lower part of the right rear connecting bracket is welded with the front part of a lower right longitudinal frame (19), the two ends of a right middle reinforcing bracket (23) are respectively welded with the end part of a right front connecting frame (5) and the front part of the upper right longitudinal frame (21), and the two ends of a right rear reinforcing bracket (25) are respectively welded with the telescopic outer pipe (30) and the lower right longitudinal frame (19) so as to reinforce the structural strength of a handrail.

As shown in fig. 1, 7 and 8, the tail gate system component includes: the device comprises a retraction action mechanism (38), a retraction action mechanism mounting bracket (39), a strength tube (40), a rubber anti-slip strip (41), an anti-slip strip fastening screw (42), a U-shaped connecting frame (43) and a U-shaped connecting frame bolt (46). The implementation mode is as follows: the bottom end of the strength pipe (40) is welded with a U-shaped connecting frame (43), a rubber anti-slip strip (41) is laid on the back of the strength pipe, the strength pipe is fixed through an anti-slip strip fastening screw (42), a folding and unfolding action mechanism mounting frame (39) is welded in front of the strength pipe, the U-shaped connecting frame (43) is connected with a left lower longitudinal frame (18) and a right lower longitudinal frame (19) through bolts (46), the other folding and unfolding action mechanism mounting frame (39) is welded at a proper position of the telescopic outer pipe (30), and the head and the tail of the folding and unfolding action mechanism (38) are connected with the strength pipe (40) and the telescopic outer pipe (30) through the bolts. When the retraction action mechanism (38) is put down, the safety tail is pushed to be put down, so that the safety tail faces the ground and is close to but not contacted with the ground, and the support effect on the vehicle body is realized to prevent overturning.

Example 2: two-stage three-point vehicle body (popular name: medium-sized)

The implementation mode is as follows: in embodiment 2, only the structure of the armrest frame system and the position of the rear stage elevating system are different from embodiment 1, and other system embodiments are the same and will not be described in detail.

As shown in fig. 9, the front end of the left longitudinal frame (50) is welded with the left front connecting frame (4), the middle part is welded with the left rear connecting frame (6), the rear end is welded with the left vertical frame (52), and a left reinforcing bracket (51) is respectively welded on the left longitudinal frame (50) and the left vertical frame (52) to reinforce the structural strength, and the right part is the same as the left part; the left end and the right end of an upper transverse frame (57) are respectively welded with the top ends of a left vertical frame (52) and a right vertical frame (55), a rear-stage lifting system (59) is arranged in the middle of the upper transverse frame (57), the top end of a telescopic outer tube (30) is welded with the middle of the upper transverse frame (57), the left end and the right end of a lower left transverse frame (53) are respectively welded with the bottom end of the left vertical frame (52) and the left side face of the telescopic outer tube (30), the left end and the right end of a lower right transverse frame (54) are respectively welded with the right side face of the telescopic outer tube (30) and the bottom end of the right vertical frame (55), and the structural strength of the rear-stage lifting system (59) is enhanced.

Example 3: first two-point vehicle body (popular name: light)

The implementation mode is as follows: as shown in fig. 10, a left front connecting frame (4) and a right front connecting frame (5) are welded on a front base cross beam (2), a left rear connecting frame (6) and a right rear connecting frame (7) are welded on a rear base cross beam (3), a lower transverse frame (71) is welded on the left front connecting frame (4) and the right front connecting frame (5), a lower transverse frame (71) is also welded on the left rear connecting frame (6) and the right rear connecting frame (7), two lower longitudinal frames (70) are respectively welded at two ends of the two lower transverse frames (71), and two lower transverse frames (71) are respectively welded at the front end and the rear end of the two lower longitudinal frames (70), so that a shelf is formed. The same embodiment is also adopted when three vertical frames (72) are respectively welded at the welding positions of the left lower longitudinal frame (70) and the three rear lower transverse frames (71), an upper longitudinal frame (75) is welded at the upper parts of the three vertical frames (72), the left end and the right end of an upper transverse frame (78) are respectively welded at the inner sides of the left upper longitudinal frame (75) and the right upper longitudinal frame (75), and the left end and the right end of the upper transverse frame and the last two vertical frames (72) are kept on a vertical plane to form the handrail frame. A left lifting system (76) is arranged at the middle position of the left side of the vehicle body, the bottom end of the telescopic outer pipe (30) is welded with a lower longitudinal frame (70) at the left side, and the top end of the telescopic outer pipe is welded with an upper longitudinal frame (75) at the left side; the right lifting system (77) is arranged at the middle position of the right side of the vehicle body, the bottom end of the telescopic outer tube (30) is welded with the lower longitudinal frame (70) of the right side, and the top end of the telescopic outer tube is welded with the upper longitudinal frame (75) of the right side. Because the vehicle is a light vehicle, the vehicle can be completely controlled by manpower, so that two safety configurations of a horizontally movable goods shelf and a double independent retractable safety tail are cancelled.