阅读说明：本技术 一种登高平台消防车伸缩臂稳固系统 (Flexible arm firm system of platform fire engine ascends a height ) 是由 李祥啟 李文明 于 2021-09-09 设计创作，主要内容包括：本发明实施例公开了一种登高平台消防车伸缩臂稳固系统,属于消防和救援装备技术领域,包括套装在一起的若干节伸缩节,每节伸缩节的顶端均设有法兰,相邻的两伸缩节之间均设有摆动臂,所述摆动臂一端铰接安装于外层的伸缩节上,所述摆动臂的另一端设有倾斜导向面,所述摆动臂上靠近所述倾斜导向面一端设有滚轮,外层伸缩节顶端的法兰上螺纹连接有调节螺钉,所述调节螺钉的端部顶靠于所述倾斜导向面上,所述滚轮的外缘顶靠于内层伸缩节的外表面。本发明解决了现有伸缩筒结构的伸缩臂最大救援高度远远小于其自身伸缩长度且稳定性差的技术问题,广泛应用于高空消防或救援中。(The embodiment of the invention discloses a stabilizing system for telescopic arms of a fire fighting truck with an ascending platform, belonging to the technical field of fire fighting and rescue equipment. The telescopic arm solves the technical problems that the maximum rescue height of the telescopic arm of the existing telescopic cylinder structure is far smaller than the self telescopic length and the stability is poor, and is widely applied to high-altitude fire fighting or rescue.)

1. A system for stabilizing a telescopic arm of a fire truck with an ascending platform comprises the telescopic arm arranged on an automobile chassis, hydraulic support legs are arranged on the automobile chassis and the telescopic arm respectively, each hydraulic support leg comprises a vertical oil cylinder and a horizontal oil cylinder, the axes of the vertical oil cylinders are vertically arranged, the cylinder body of each vertical oil cylinder is arranged on the piston rod of each horizontal oil cylinder, each telescopic arm comprises a plurality of telescopic joints which are sleeved together, the top end of each telescopic joint is provided with a flange, the inner telescopic joint penetrates through the flange at the top end of the outer telescopic joint, the system is characterized in that a swing arm is arranged between every two adjacent telescopic joints, one end of each swing arm is hinged and arranged on the outer telescopic joint, the other end of each swing arm is provided with an inclined guide surface, one end of each swing arm, which is close to the inclined guide surface, is provided with a roller, and the flange at the top end of the outer telescopic joint is in threaded connection with an adjusting screw, the end part of the adjusting screw is propped against the inclined guide surface, and the outer edge of the roller is propped against the outer surface of the inner-layer telescopic joint under the action of the adjusting screw.

2. The system for stabilizing the telescopic arm of a fire fighting truck at an ascending platform according to claim 1, wherein the cross-sectional shape of the telescopic joint is square, at least two sets of rollers are supported on each panel of the inner telescopic joint, and the rollers are respectively positioned at the corners of the corresponding telescopic joint.

3. The system for stabilizing the telescopic arm of the elevating platform fire truck as claimed in claim 2, wherein a locking nut is provided between the adjusting screw and the flange.

4. The system for stabilizing the telescopic arm of the fire fighting truck with the climbing platform according to claim 3, wherein an inner limiting block is arranged on the outer surface of the bottom of the inner telescopic joint, and correspondingly, an outer limiting block is arranged on the inner surface of the top of the outer telescopic joint.

5. The climbing platform fire engine telescopic boom stabilizing system according to claim 4, wherein the upper surfaces of all inner limiting blocks are located on the same horizontal plane, and the lower surfaces of all outer limiting blocks are located on the same horizontal plane.

6. The elevating platform fire truck telescopic boom stabilizing system according to any one of claims 1 to 5, wherein a rodless cavity of the horizontal cylinder communicates with an oil port A of a first directional valve, a rod cavity of the horizontal cylinder communicates with an oil port B of the first directional valve, an oil port P of the first directional valve communicates with an oil inlet pipeline, an oil port T of the first directional valve communicates with an oil return pipeline, a rodless cavity of the vertical cylinder connects with an oil port A of a second directional valve through a first hydraulic control one-way valve, a rod cavity of the vertical cylinder connects with an oil port B of the second directional valve through a second hydraulic control one-way valve, a hydraulic control port of the first hydraulic control one-way valve connects with an oil port B of the second directional valve, a hydraulic control port of the second hydraulic control one-way valve connects with an oil port A of the second directional valve, a P of the second directional valve communicates with an oil inlet pipeline, and an oil port T of the second directional valve communicates with an oil return pipeline, the second reversing valve is connected with the inclination angle sensor.

7. The system for stabilizing the telescopic arm of the elevating platform fire truck as claimed in claim 6, wherein the first reversing valve is an O-shaped three-position four-way electromagnetic reversing valve, the second reversing valve is a Y-shaped three-position four-way electromagnetic reversing valve, and an electromagnetic coil of the second reversing valve is connected with the tilt angle sensor.

8. The system for stabilizing the telescopic arm of the elevating platform fire truck as claimed in claim 7, wherein the horizontal cylinder comprises a first cylinder body installed at a fixed position, a second cylinder body is slidably installed in the first cylinder body, a third cylinder body is slidably installed in the second cylinder body, the end of the third cylinder body is connected with the vertical cylinder body, the first cylinder body is communicated with the second cylinder body, a plunger slidably installed in the second cylinder body is fixedly installed at the end of the third cylinder body, a third central cylinder is arranged in the third cylinder body, an oil through hole is arranged at one end of the third central cylinder far away from the plunger, the other end of the third central cylinder penetrates through the plunger and extends into the second cylinder body, only a second central cylinder is sleeved in the third central cylinder, the second central cylinder is matched with the second cylinder body, and a first central cylinder is sleeved in the second central cylinder, the first center cylinder is matched with the first cylinder body, the end of the first center cylinder is connected with a horizontal first working oil port at the end of the first cylinder body, a horizontal second working oil port is arranged at the end of the first cylinder body and is communicated with an oil port A of the first reversing valve, and the horizontal first working oil port is communicated with an oil port B of the first reversing valve.

9. The system for stabilizing the telescopic arm of the elevating platform fire truck as recited in claim 8, wherein a first sleeve and a second sleeve are disposed in parallel in the third cylinder, one end of the first sleeve is connected to the first hydraulic control check valve, the other end of the first sleeve passes through the plunger and extends into the second cylinder, one end of the second sleeve is connected to the second hydraulic control check valve, the other end of the second sleeve passes through the plunger and extends into the second cylinder, a third sleeve is sleeved in the first sleeve, a fourth sleeve is sleeved in the second sleeve, the third sleeve and the fourth sleeve are both adapted to the second cylinder, a fifth sleeve is sleeved in the third sleeve, a sixth sleeve is sleeved in the fourth sleeve, the fifth sleeve and the sixth sleeve are both adapted to the first cylinder, and the end of the fifth sleeve is connected to the oil port A of the second reversing valve, and the end part of the sixth sleeve is connected with the oil port B of the second reversing valve.

Technical Field

The embodiment of the invention relates to the technical field of fire fighting and rescue equipment, in particular to a stabilizing system for a telescopic arm of a fire truck with an ascending platform.

Background

At present, high altitude fire rescue car's telescopic boom usually has two kinds of forms, one kind is the crank arm structure, another kind is telescopic tube structure, crank arm structure festival number is few, telescopic tube structure festival number is many, and in the telescopic boom of current telescopic tube structure, the sliding gap between each telescopic section is great, consequently, it is serious to lead to the telescopic section to stretch out the back and rock, so mostly adopt the slope to go up and down, utilize its dead weight to overcome the sliding gap between the telescopic section, this is just so that telescopic boom maximum rescue height of telescopic tube structure is less than its self length that stretches out and draws back far away, poor stability, be difficult to exert telescopic tube structure telescopic boom's advantage.

Therefore, in the technical field of fire fighting and rescue equipment, the need for research and improvement of the telescopic arm stabilizing system of the elevating platform fire truck still exists, which is a research focus and a focus in the technical field of fire fighting and rescue equipment at present and is a starting point of the invention.

Disclosure of Invention

Therefore, the embodiment of the invention provides a stabilizing system for a telescopic arm of a fire truck with a climbing platform, which aims to solve the technical problems that the maximum rescue height of the telescopic arm of the existing telescopic cylinder structure is far smaller than the self telescopic length and the stability is poor.

In order to achieve the above object, the embodiments of the present invention provide the following technical solutions:

according to the embodiment of the invention, the stabilizing system for the telescopic arm of the fire fighting truck with the ascending platform comprises the telescopic arm arranged on an automobile chassis, hydraulic support legs are arranged on the automobile chassis and the telescopic arm respectively, each hydraulic support leg comprises a vertical oil cylinder and a horizontal oil cylinder, the axes of the vertical oil cylinders are vertically arranged, the cylinder body of each vertical oil cylinder is arranged on the piston rod of each horizontal oil cylinder, each telescopic arm comprises a plurality of telescopic joints which are sleeved together, a flange is arranged at the top end of each telescopic joint, the inner-layer telescopic joint penetrates through the flange at the top end of the outer-layer telescopic joint, a swing arm is arranged between every two adjacent telescopic joints, one end of each swing arm is hinged and arranged on the outer-layer telescopic joint, an inclined guide surface is arranged at the other end of each swing arm, a roller wheel is arranged at one end, close to the inclined guide surface, and an adjusting screw is connected on the flange at the top end of the outer-layer telescopic joint through threads, the end part of the adjusting screw is propped against the inclined guide surface, and the outer edge of the roller is propped against the outer surface of the inner-layer telescopic joint under the action of the adjusting screw.

Furthermore, the cross-sectional shape of telescopic joint is square, all leans on two groups of gyro wheels that set up at an interval all at least on being located every panel of inlayer telescopic joint, the gyro wheel is located the bight position of corresponding telescopic joint respectively.

Furthermore, a locking nut is arranged between the adjusting screw and the flange.

Further, an inner limiting block is arranged on the outer surface of the bottom of the inner-layer telescopic joint, and correspondingly, an outer limiting block is arranged on the inner surface of the top of the outer-layer telescopic joint.

Furthermore, the upper surfaces of all the inner limiting blocks are located on the same horizontal plane, and the lower surfaces of all the outer limiting blocks are located on the same horizontal plane.

Further, a rodless cavity of the horizontal oil cylinder is communicated with an oil port A of the first reversing valve, a rod cavity of the horizontal oil cylinder is communicated with an oil port B of the first reversing valve, an oil port P of the first reversing valve is communicated with an oil inlet pipeline, an oil port T of the first reversing valve is communicated with an oil return pipeline, a rodless cavity of the vertical oil cylinder is connected with an oil port A of the second reversing valve through the first hydraulic control one-way valve, a rod cavity of the vertical oil cylinder is connected with an oil port B of the second reversing valve through the second hydraulic control one-way valve, an oil port B of the second reversing valve is connected with an oil port B of the first hydraulic control one-way valve, an oil port A of the second reversing valve is connected with an oil port A of the second hydraulic control one-way valve, an oil port P of the second reversing valve is communicated with an oil inlet pipeline, an oil port T of the second reversing valve is communicated with an oil return pipeline, and the second reversing valve is connected with an inclination angle sensor.

Furthermore, the first reversing valve is an O-shaped three-position four-way electromagnetic reversing valve, the second reversing valve is a Y-shaped three-position four-way electromagnetic reversing valve, and an electromagnetic coil of the second reversing valve is connected with the inclination angle sensor.

Further, the horizontal oil cylinder comprises a first cylinder body arranged at a fixed position, a second cylinder body is arranged in the first cylinder body in a sliding mode, a third cylinder body is arranged in the second cylinder body in a sliding mode, the end portion of the third cylinder body is connected with the vertical oil cylinder, the first cylinder body is communicated with the second cylinder body, a plunger piston which is arranged in the second cylinder body in a sliding mode is fixedly arranged at the end portion of the third cylinder body, a third central cylinder is arranged in the third cylinder body, an oil through hole is formed in one end, far away from the plunger piston, of the third central cylinder, the other end of the third central cylinder penetrates through the plunger piston and extends into the second cylinder body, only a second central cylinder is sleeved in the third central cylinder, the second central cylinder is matched with the second cylinder body, a first central cylinder is sleeved in the second central cylinder, the first central cylinder is matched with the first cylinder body, the end portion of the first central cylinder is connected with the first horizontal oil hole in the end portion of the first cylinder body to work, the end part of the first cylinder body is provided with a horizontal second working oil port which is communicated with the oil port A of the first reversing valve, and the horizontal first working oil port is communicated with the oil port B of the first reversing valve.

Furthermore, a first sleeve and a second sleeve are arranged in the third cylinder body in parallel, one end of the first sleeve is connected with the first hydraulic control one-way valve, the other end of the first sleeve penetrates through the plunger and extends into the second cylinder body, one end of the second sleeve is connected with the second hydraulic control one-way valve, the other end of the second sleeve penetrates through the plunger and extends into the second cylinder body, a third sleeve is sleeved in the first sleeve, a fourth sleeve is sleeved in the second sleeve, the third sleeve and the fourth sleeve are matched with the second cylinder body, a fifth sleeve is sleeved in the third sleeve, a sixth sleeve is sleeved in the fourth sleeve, the fifth sleeve and the sixth sleeve are matched with the first cylinder body, the end part of the fifth sleeve is connected with the oil port A of the second reversing valve, and the end part of the sixth sleeve is connected with the oil port B of the second reversing valve.

The embodiment of the invention has the following advantages:

(1) according to the embodiment of the invention, the swing arm is arranged at the position, close to the flange, of the outer-layer telescopic joint, the roller is arranged on the swing arm, and the outer edge of the roller is abutted against the outer surface of the inner-layer telescopic joint through the abutting of the adjusting screw against the swing arm, so that the sliding gap between the adjacent telescopic joints is reduced, the stability of the telescopic arm in the telescopic process is improved, the structure can be vertically lifted, and the maximum rescue height of the telescopic arm is equal to the self telescopic length.

(2) Due to the fact that the inner limiting block and the outer limiting block are arranged in the corresponding positions, on one hand, the inner-layer telescopic joint is more stable in the telescopic process, the limiting effect of the maximum lifting position of the inner-layer telescopic joint is achieved, the inner-layer telescopic joint is prevented from being separated, on the other hand, after the inner limiting block is contacted with the outer limiting block, the coaxiality of the inner-layer telescopic joint and the outer-layer telescopic joint is consistent, the verticality of the telescopic joint in normal work is guaranteed, and the using performance of the telescopic joint is further enhanced.

(3) The first hydraulic control one-way valve and the second hydraulic control one-way valve are arranged, the current pressure of the vertical oil cylinder can be kept, hydraulic oil leakage caused by bearing change is avoided, the output quantity of a piston rod of the vertical oil cylinder is stabilized, the change of the inclination angle of the chassis can be monitored at any time due to the fact that the second reversing valve is connected with the inclination angle sensor, the level of the chassis is adjusted in time, the telescopic boom is kept in a vertical state all the time, the stability of the telescopic boom is guaranteed, and the smooth proceeding of fire rescue is guaranteed.

(4) Because the horizontal oil cylinder is set as a secondary oil cylinder, the horizontal oil cylinder of the structure increases the horizontal movement distance of the vertical oil cylinder, increases the supporting area, further improves the supporting stability and further improves the stable supporting performance of the telescopic arm.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary, and that other embodiments can be derived from the drawings provided by those of ordinary skill in the art without inventive effort.

The structures, ratios, sizes, and the like shown in the present specification are only used for matching with the contents disclosed in the specification, so as to be understood and read by those skilled in the art, and are not used to limit the conditions that the present invention can be implemented, so that the present invention has no technical significance, and any structural modifications, changes in the ratio relationship, or adjustments of the sizes, without affecting the effects and the achievable by the present invention, should still fall within the range that the technical contents disclosed in the present invention can cover.

FIG. 1 is a schematic structural diagram of an embodiment of the present invention;

FIG. 2 is a schematic view of a connection structure of two adjacent telescopic joints according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of structure E-E of FIG. 2;

FIG. 4 is an enlarged schematic view of A in FIG. 2;

FIG. 5 is a hydraulic schematic of a hydraulic leg in an embodiment of the invention;

FIG. 6 is a schematic structural view of a hydraulic leg in an embodiment of the invention;

in the figure: 1. the hydraulic support comprises an automobile chassis, 2, a telescopic arm, 3, a hydraulic support leg, 4, an outer telescopic joint, 401, a flange, 5, an inner telescopic joint, 6, a swing arm, 601, an inclined guide surface, 7, an adjusting screw, 8, a locking nut, 9, an inner limiting block, 10, a roller, 11, a horizontal oil cylinder, 1101, a first cylinder body, 1102, a second cylinder body, 1103, a third cylinder body, 1104, a plunger, 1105, a first central cylinder, 1106, a second central cylinder, 1107, a third central cylinder, 1108, an oil through port, 1109, a horizontal first working oil port, 1110, a horizontal second working oil port, 12, a vertical oil cylinder, 1201, a first sleeve, 1202, a second sleeve, 1203, a third sleeve, 1204, a fourth sleeve, 1205, a fifth sleeve, 1206, a sixth sleeve, 13, an oil inlet pipeline, 14, an oil return pipeline, 15, a first reversing valve, 16, a second reversing valve, 17, a first one-way valve, 18, a first one-way valve, a hydraulic control valve, 18, a hydraulic control valve, a second hydraulic control one-way valve 19, an inclination angle sensor 20 and an outer limiting block.

Detailed Description

The present invention is described in terms of particular embodiments, other advantages and features of the invention will become apparent to those skilled in the art from the following disclosure, and it is to be understood that the described embodiments are merely exemplary of the invention and that it is not intended to limit the invention to the particular embodiments disclosed. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the present specification, the terms "front", "rear", "left", "right" and "middle" are used for clarity of description only, and are not intended to limit the scope of the present invention, and changes or modifications of the relative relationship thereof are also regarded as the scope of the present invention without substantial changes in the technical content.

As shown in fig. 1, an embodiment of the present invention provides a stabilizing system for a telescopic boom of a fire truck with a climbing platform, including a telescopic boom 2 mounted on a vehicle chassis 1, wherein hydraulic legs 3 are mounted on both the vehicle chassis 1 and the telescopic boom 2, each hydraulic leg 3 includes a vertical cylinder 12 and a horizontal cylinder 11, the axes of which are vertically arranged, a cylinder body of the vertical cylinder 12 is mounted on a piston rod of the horizontal cylinder 11, as shown in fig. 2, 3 and 4, the telescopic boom 2 includes a plurality of telescopic joints which are sleeved together, a flange 401 is disposed at the top end of each telescopic joint, an inner telescopic joint 5 penetrates through the flange 401 at the top end of an outer telescopic joint 4, a gap between a flange hole at the top end of the outer telescopic joint 4 and the outer surface of the inner telescopic joint 5 is a sliding gap, a swing arm 6 is disposed between two adjacent telescopic joints, one end of the swing arm 6 is hinged to the outer telescopic joint, an inclined guide surface 601 is disposed at the other end of the swing arm 6, the included angle between the inclined guide surface 601 and the symmetrical center plane of the swing arm 6 is an acute angle, one end of the swing arm 6, which is close to the inclined guide surface 601, is provided with a roller 10, the rotation center of the swing arm 6 is parallel to the rotation center of the roller 10, the flange 401 at the top end of the outer telescopic joint 4 is connected with an adjusting screw 7 through threads, the end part of the adjusting screw 7 abuts against the inclined guide surface 601, under the action of the adjusting screw 7, the outer edge of the roller 10 abuts against the outer surface of the inner telescopic joint 5, so that the shaking gap between the two adjacent telescopic joints is reduced, and the inner telescopic joint 5 is more stable in the telescopic process.

The cross section of the telescopic joint is square, each telescopic joint is of a square tubular structure surrounded by four square plates, the telescopic joint with the square cross section avoids rotation in the telescopic process, and the stability of the telescopic joint is improved.

Each panel of the inner expansion joint 5 at least leans against two groups of rollers 10 which are arranged at intervals, and the rollers 10 are respectively positioned at the corner positions of the corresponding expansion joints. If the breadth of the panel is larger, more groups of rollers 10 can be arranged, and the corresponding rollers 10 can be arranged at the corner position and the middle position of the telescopic joint so as to ensure that the telescopic process of the inner-layer telescopic joint 5 is more stable.

Be equipped with lock nut 8 between adjusting screw 7 and the flange 401, when the gyro wheel 10 outer fringe was leaned on in 5 outer surfaces of inlayer expansion joint, lock nut 8 screwed for 8 terminal surfaces of lock nut lean on the flange 401 terminal surface, avoided the expansion joint flexible in-process adjusting screw 7 not hard up, and lead to inlayer expansion joint 5 to produce too big rocking gap.

An inner limiting block 9 used for limiting a sliding gap is arranged between every two adjacent telescopic joints, and the gap between the inner limiting block 9 and the inner surface of the outer telescopic joint 4 needs to be adjusted to be smaller than the sliding gap, so that the inner telescopic joint 5 is more stable in the telescopic process.

Be equipped with interior stopper 9 on the surface of inlayer telescopic joint 5 bottom, the clearance between interior stopper 9 and the 4 internal surfaces of outer telescopic joint will be adjusted to being less than the slip clearance, and is corresponding, is equipped with outer stopper 20 on the internal surface at outer telescopic joint 4 top, and similarly, the clearance between interior stopper 9 and the 4 internal surfaces of outer telescopic joint will be adjusted to being less than the slip clearance for inlayer telescopic joint 5 flexible in-process is more firm. All be equipped with stopper 9 and outer stopper 20 in a set of at least on every panel of inlayer telescopic joint 5, the skilled person in the art can be according to the size of telescopic joint panel breadth, select the use quantity of interior stopper 9 and outer stopper 20 on every panel to and arrange the mounted position of interior stopper 9 and outer stopper 20, no longer describe herein. The upper surfaces of all the inner limiting blocks 9 are positioned on the same horizontal plane, the lower surfaces of all the outer limiting blocks 20 are positioned on the same horizontal plane, and after the inner limiting blocks 9 are contacted with the outer limiting blocks 20, the coaxiality of the inner-layer expansion joint 5 and the outer-layer expansion joint 4 is consistent, the verticality of the expansion joint in normal work is ensured, and the using performance of the telescopic joint is further enhanced.

In the embodiment of the invention, the swing arm 6 is arranged at the position, close to the flange 401, of the outer telescopic joint 4, the roller 10 is arranged on the swing arm 6, the adjusting screw 7 is abutted against the swing arm 6, so that the outer edge of the roller 10 is abutted against the outer surface of the inner-layer telescopic joint 5, thereby reducing the sliding clearance between the adjacent telescopic joints, and the inner limit block 9 is arranged at the bottom of the inner telescopic joint 5, so that the inner telescopic joint 5 is more stable in the telescopic process, meanwhile, the outer limiting block 20 has a limiting function and effectively prevents the inner-layer telescopic joint 5 from falling off, and when the inner-layer telescopic joint 5 extends to the maximum length, namely, the inner limit block 9 is abutted against the outer limit block 20, so that the axes of the inner layer expansion joint 5 and the outer layer expansion joint 4 are ensured to be consistent, therefore, this structure can use vertical lift, and the stability can be high, has realized that flexible arm 2 is the biggest rescue height and has equaled its self flexible length.

As shown in fig. 5, a rodless cavity of the horizontal cylinder 11 is communicated with an oil port a of the first directional valve 15, a rod cavity of the horizontal cylinder 11 is communicated with an oil port B of the first directional valve 15, an oil port P of the first directional valve 15 is communicated with the oil inlet pipeline 13, an oil port T of the first directional valve 15 is communicated with the oil return pipeline 14, a rodless cavity of the vertical cylinder 12 is connected with an oil port a of the second directional valve 16 through the first pilot operated check valve 17, a rod cavity of the vertical cylinder 12 is connected with an oil port B of the second directional valve 16 through the second pilot operated check valve 18, a pilot operated port of the second pilot operated check valve 18 is connected with an oil port a of the second directional valve 16, a pilot operated port of the first pilot operated check valve 17 is connected with an oil port B of the second directional valve 16, the first pilot operated check valve 17 and the second pilot operated check valve 18 can maintain the current pressure of the vertical cylinder 12, thereby preventing hydraulic oil leakage caused by load bearing change and stabilizing the output of a piston rod of the vertical cylinder 12, the second reversing valve 16 is connected with an inclination angle sensor 19, a P oil port of the second reversing valve 16 is communicated with the oil inlet pipeline 13, a T oil port of the second reversing valve 16 is communicated with the oil return pipeline 14, the first reversing valve 15 is an O-shaped three-position four-way electromagnetic reversing valve, the second reversing valve 16 is a Y-shaped three-position four-way electromagnetic reversing valve, specifically, an electromagnetic coil of the second reversing valve 16 is connected with the inclination angle sensor 19, the inclination angle sensor 19 is usually installed on the telescopic arm 2 and used for detecting whether the telescopic arm 2 is vertical to the ground in the lifting process, the inclination angle sensor 19 is common equipment for technicians in the field, the equipment can be purchased, installed and used according to required models, when the equipment is used, the inclination angle sensor 19 feeds back detection signals to a control unit, the control unit is usually a PLC or a single chip microcomputer, and then the control unit controls the corresponding reversing valve to control the corresponding hydraulic execution element. When the automobile chassis is in operation, a rodless cavity of a horizontal oil cylinder 11 is filled with oil, the horizontal oil cylinder 11 drives a vertical oil cylinder 12 to move horizontally, after the horizontal oil cylinder 11 extends to the maximum position, a first reversing valve 15 is locked, an O-shaped three-position four-way electromagnetic reversing valve is switched to the middle position, so that the horizontal oil cylinder 11 keeps the current state, the rodless cavity of the vertical oil cylinder 12 starts to be filled with oil, meanwhile, a second hydraulic control one-way valve 18 is opened by hydraulic oil, so that hydraulic oil in a rod cavity of the vertical oil cylinder 12 can return to an oil return pipeline 14 to support the automobile chassis 1 to rise, after four corners of the automobile chassis 1 are all horizontal, a Y-shaped three-position four-way electromagnetic reversing valve is switched to the middle position, the rod cavity of the vertical oil cylinder 12 does not fill with oil any more, under the action of a first hydraulic control one-way valve 17 and the second hydraulic control one-way valve 18, the vertical oil cylinder 12 keeps at the current position, and once one corner of the automobile chassis 1 inclines due to overlarge bearing, the tilt sensor 19 is communicated with the electromagnetic coil of the second reversing valve 16, the rodless cavity of the vertical oil cylinder 12 starts to feed oil, the piston rod of the vertical oil cylinder 12 extends out to compensate the tilt amount, and after the tilt sensor 19 is horizontal, the vertical oil cylinder 12 is kept at the position.

As is well known, the larger the supporting area of the automobile chassis 1 is, the higher the stability of the automobile chassis 1 is, and accordingly the stability of the telescopic arm 2 is, for this reason, the horizontal cylinder 11 is set as a two-stage hydraulic cylinder, and the horizontal extension length of the hydraulic leg 3 is increased. Specifically, as shown in fig. 6, the horizontal cylinder 11 includes a first cylinder 1101 installed at a fixed position, a second cylinder 1102 is installed in the first cylinder 1101 in a sliding manner, a third cylinder 1103 is installed in the second cylinder 1102 in a sliding manner, the third cylinder 1103 is equivalent to a piston rod of the horizontal cylinder 11, sliding seal mechanisms are respectively installed between the second cylinder 1102 and the first cylinder 1101 and between the second cylinder 1102 and the third cylinder 1103 so as to prevent hydraulic oil from leaking, an end portion of the third cylinder 1103 is connected to the vertical cylinder 12, the first cylinder 1101 is communicated with the second cylinder 1102, an end portion of the third cylinder 1103 is fixedly installed with a plunger 1104 installed in the second cylinder 1102 in a sliding manner, a third central cylinder 1107 is installed in the third cylinder 1103, an end of the third central cylinder 1107 away from the plunger is provided with an oil through port 1108, the other end of the third central cylinder passes through the plunger 1104 and extends into the second cylinder 1102, only the third central cylinder 1107 is installed in the third central cylinder 1103, the second center cylinder 1106 is matched with the second cylinder body 1102, the first center cylinder 1105 is sleeved in the second center cylinder 1106, the first center cylinder 1105 is matched with the first cylinder body 1101, the end part of the first center cylinder 1105 is connected with a horizontal first working oil port 1109 at the end part of the first cylinder body 1101, the horizontal first working oil port 1109 is communicated with an oil through port 1108, a horizontal second working oil port 1110 is arranged at the end part of the first cylinder body 1101, the horizontal second working oil port 1110 is communicated with an inner cavity of the first cylinder body 1101, the horizontal second working oil port 1110 is communicated with an oil port A of the first reversing valve 15, and the horizontal first working oil port 1109 is communicated with an oil port B of the first reversing valve 15. When the horizontal second working oil port 1110 performs oil feeding, hydraulic oil in the oil feeding pipeline 13 enters the first cylinder 1101, the plunger 1104 is firstly pushed to drive the third cylinder 1103 to stretch out, meanwhile, the vertical oil cylinder 12 is driven to move horizontally, hydraulic oil in the third cylinder 1103 returns to the oil return pipeline 14 through the oil through port 1108, after the third cylinder 1103 completely stretches out, oil feeding continues to be performed in the first cylinder 1101, the second cylinder 1102 continues to extend outwards, meanwhile, the vertical oil cylinder 12 is driven to continue to move horizontally, the horizontal oil cylinder 11 of the structure increases the horizontal moving distance of the vertical oil cylinder 12, the supporting area is increased, and further, the supporting stability is improved.

A first sleeve 1201 and a second sleeve 1202 are arranged in parallel in the third cylinder 1103, one end of the first sleeve 1201 is connected with the first pilot-operated check valve 17, the other end of the first sleeve 1201 penetrates through the plunger 1104 and extends into the second cylinder 1102, one end of the second sleeve 1202 is connected with the second pilot-operated check valve 18, the other end of the second sleeve passes through the plunger 1104 and extends into the second cylinder 1102, a third sleeve 1203 is sleeved in the first sleeve 1201, a fourth sleeve 1204 is sleeved in the second sleeve 1202, the third sleeve 1203 and the fourth sleeve 1204 are both matched with the second cylinder 1102, a fifth sleeve 1205 is sleeved in the third sleeve 1203, a sixth sleeve 1204 is sleeved in the fourth sleeve 1201, the fifth sleeve 1205 and the sixth sleeve 1206 are both matched with the first cylinder 1101, sliding sealing structures are arranged between the first sleeve 1203 and the third sleeve 1203 and between the third sleeve 1203 and the second sleeve 1202 to prevent hydraulic oil from leaking, and sliding sealing structures are also arranged between the second sleeve 1204 and the fourth sleeve 1206 and between the fourth sleeve 1204, to avoid hydraulic oil leakage, the end of the fifth sleeve 1205 is connected to the port a of the second directional valve 16, and the end of the sixth sleeve 1206 is connected to the port B of the second directional valve 16. The structure makes full use of the internal space of the horizontal oil cylinder 11, embeds the oil inlet and oil return pipeline 14 of the vertical oil cylinder 12, and does not need to drag a plurality of external hydraulic oil pipes, and the structure is simple and practical.

The embodiment of the invention is generally respectively arranged at four corners of the automobile chassis 1, has large supporting area and high stability, can monitor the inclination angle change of the chassis at any time, and can adjust the chassis level in time, thereby ensuring the smooth proceeding of fire rescue.

Although the invention has been described in detail above with reference to a general description and specific examples, it will be apparent to one skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.