HK1236179B - Telescopic connection component and aerial work platform - Google Patents

Description

Telescopic connection assembly and aerial work platform

【Technical field】

The present invention relates to the field of engineering machinery, in particular to an engineering work vehicle, and more specifically to a telescopic connection assembly and an aerial work platform.

[Background Technology]

Aerial work platforms are advanced aerial work equipment that significantly improve the efficiency, safety, and comfort of aerial construction workers while reducing labor intensity. They have long been widely used in developed countries. Their use in my country is also growing. Initially, they were used for general municipal streetlight maintenance and garden tree pruning. With the rapid development of my country's economy, demand for aerial work platforms is growing in engineering construction, industrial installation, equipment maintenance, plant maintenance, shipbuilding, power generation, municipal administration, airports, communications, gardening, and transportation.

The forearm connecting the operating platform and the main arm (which can be a telescopic connecting component) in a traditional aerial work platform adopts a parallelogram structure. The specific structure is: the two connection points on the operating platform are respectively hinged to the two connection points on the forearm head (connected to the main arm) through two connecting arms, and the line connecting the two connection points on the operating platform is parallel to the line connecting the two connection points on the forearm head, so that the line connecting the two connecting arms and the two connection points on the operating platform and the line connecting the two connection points on the forearm head form a parallelogram, and then the boom cylinder, leveling cylinder and other components are matched to give the forearm the boom with boom and leveling functions; since the existing forearm adopts a parallelogram structure, its horizontal reach is limited by the length of the connecting arm and cannot meet the work requirements with a larger horizontal reach; in addition, the parallelogram forearm structure makes the aerial work platform relatively less flexible in the working area.

Therefore, it is necessary to provide an improved connection structure for connecting the operating platform and the main arm and a corresponding aerial work platform to overcome the shortcomings and deficiencies of the above-mentioned prior art.

[Summary of the invention]

The purpose of the present invention is to solve the above-mentioned problems and provide a telescopic connection assembly and an aerial work platform. The telescopic connection assembly not only has a large horizontal extension, thereby increasing the working range of the aerial work platform, but also has high structural strength and structural stability, which can greatly ensure the safety of the aerial work platform.

To achieve this purpose, the present invention provides a telescopic connection assembly for telescopically connecting a telescopic transmission assembly on an aerial work platform to an operating platform, the telescopic connection assembly comprising: an outer arm, an inner arm slidably disposed in the outer arm and capable of extending from one end of the outer arm, and a small arm telescopic cylinder disposed between the outer arm and the inner arm.

Specifically, the arm telescopic oil cylinder includes a cylinder body and a piston rod slidably arranged in the cylinder body. The cylinder body is fixed to the outer arm, and the extended end of the piston rod is fixed to the inner arm.

Preferably, the cylinder body is fixed to the outer wall of the outer arm, and the extended end of the piston rod is fixed to the outer wall of the inner arm.

Correspondingly, the present invention also provides an aerial work platform, comprising: a vehicle body, a telescopic transmission assembly, a telescopic connection assembly described in any of the above technical solutions, and an operating platform that are movably connected in sequence; support members are provided between the vehicle body and the telescopic transmission assembly and between the telescopic transmission assembly and the telescopic connection assembly.

Optionally, the support member between the telescopic transmission assembly and the telescopic connection assembly is a luffing cylinder.

Optionally, the support member between the telescopic transmission assembly and the telescopic connection assembly is a first leveling cylinder; one end of the telescopic connection assembly connected to the telescopic transmission assembly is hinged with a small arm head; one end of the first leveling cylinder is hinged to the telescopic transmission assembly, and the other end is hinged to the small arm head.

Furthermore, the telescopic connection assembly also includes a jib luffing cylinder, one end of which is hinged to the jib head, and the other end is hinged to the outer wall of the outer arm, so that the jib head, outer arm and jib luffing cylinder constitute a triangular luffing mechanism.

Furthermore, a third leveling oil cylinder is provided between the telescopic connection assembly and the operating table. One end of the third leveling oil cylinder is hinged to the inner arm, and the other end is hinged to the swing cylinder fixed to the operating table.

Optionally, the swing cylinder is provided with an angle sensor that cooperates with the third leveling cylinder.

Optionally, a second leveling cylinder is provided between the jib head and the telescopic connection assembly, one end of the second leveling cylinder is hinged to the jib head, and the other end is hinged to the outer wall of the outer arm; the cavity of the second leveling cylinder is connected to the cavity of the third leveling cylinder through an oil pipe.

Compared with the prior art, the present invention has the following advantages:

In the technical solution of the present invention, since the telescopic connection assembly includes: an outer arm, an inner arm slidably arranged in the outer arm and capable of extending from one end of the outer arm, and a small arm telescopic cylinder arranged between the outer arm and the inner arm, the small arm telescopic cylinder can drive the inner arm to extend from the outer arm and retract into the outer arm. In this process, since the inner arm can be extended from the outer arm, it can increase the horizontal extension distance of the operating platform connected to the inner arm, thereby expanding the working range.

Secondly, in the technical solution of the present invention, corresponding leveling mechanisms are provided between the telescopic transmission assembly and the telescopic connection assembly, and between the telescopic connection assembly and the operating table, which can ensure that the operating table moves more smoothly in all directions on the horizontal plane during work, thereby ensuring the personal safety of workers.

Furthermore, the telescopic connection assembly adopts a structural method in which the inner arm is slidably arranged in the outer arm, and relevant support members are arranged between the telescopic transmission assembly and the telescopic connection assembly and between the telescopic connection assembly and the operating table. These structural methods can make the aerial work platform have higher structural strength and structural stability, thereby improving the safety of the aerial work platform.

Therefore, the telescopic connection assembly in the present invention not only has a larger horizontal extension, allowing the operating platform to extend to a farther area on the horizontal plane, thereby increasing the working range of the aerial work platform, but also has higher structural strength and structural stability, which can greatly improve the safety of the aerial work platform.

【Brief Description of the Drawings】

FIG1 is a schematic structural diagram of a typical embodiment of an aerial work platform according to the present invention;

FIG2 is a partial enlarged view of the portion M in FIG1 ;

FIG3 is a schematic structural diagram of another state of the front end component of the aerial work vehicle shown in FIG1 , wherein the front end component includes a telescopic connection assembly, an operating platform and related connection components;

FIG4 is a schematic structural diagram of the telescopic transmission assembly of the aerial work platform shown in FIG1 ;

FIG5 is a partial enlarged view of portion A in FIG4 ;

FIG6 is a partial enlarged view of portion B in FIG4 ;

FIG7 is a schematic structural diagram of the telescopic transmission assembly shown in FIG4 in an extended state;

FIG8 is a schematic structural diagram of the key transmission components within the telescopic transmission assembly shown in FIG4 , wherein the key transmission components include a first sprocket, a second sprocket, a stretching chain, a return chain, and a telescopic cylinder;

FIG9 is a schematic structural diagram of another state of the internal key transmission components of the telescopic transmission assembly shown in FIG4;

FIG10 is a schematic structural diagram of another state of the internal key transmission components of the telescopic transmission assembly shown in FIG4;

FIG11 is a schematic structural diagram of the telescopic oil cylinder of the telescopic transmission assembly shown in FIG4 ;

FIG12 is a partial enlarged view of portion C in FIG11 ;

FIG13 is a schematic structural diagram of a front end component of another embodiment of an aerial work platform in the present invention.

[Specific implementation method]

The present invention will be further described below in conjunction with the accompanying drawings and exemplary embodiments, wherein identical reference numerals throughout the accompanying drawings refer to identical components. In addition, if detailed description of known techniques is unnecessary for illustrating features of the present invention, it will be omitted.

A structural schematic diagram of a typical embodiment of an aerial work platform provided by the present invention is shown in Figures 1 to 12. The aerial work platform includes a vehicle body 1, a telescopic transmission assembly 2 pivotally connected to the vehicle body 1, and an operating table 3 connected to the end of the telescopic transmission assembly 2 via a telescopic connection assembly 5.

It should be noted that the vehicle body 1 includes a frame, a drive system arranged on the frame, and a control box electrically connected to the drive system, and the control box can be flipped and arranged on the side of the frame; the drive system includes a drive mechanism, a transmission mechanism, a wheel assembly and a control system, etc., and the control box is also electrically connected to the control system; related control devices electrically connected to the control system can also be set on the operating table.

The telescopic connection assembly 5 includes an outer arm 51 , an inner arm 52 slidably disposed in the outer arm 51 and capable of extending from one end of the outer arm 51 , and an arm telescopic cylinder 53 disposed between the outer arm 51 and the inner arm 52 .

It should be noted that the arm telescopic cylinder 53 includes a cylinder body (not marked) and a piston rod (not marked) slidably arranged in the cylinder body; preferably, the cylinder body is fixed to the outer wall of the outer arm 51, and the protruding end of the piston rod is fixed to the outer wall of the inner arm 52.

A first leveling cylinder 55 is provided between the telescopic transmission assembly 2 and the telescopic connection assembly 5, and an arm head 54 is hingedly connected to one end of the telescopic connection assembly 5 connected to the telescopic transmission assembly 2; one end of the first leveling cylinder 55 is hinged to the telescopic transmission assembly 2, and the other end is hinged to the arm head 54; the telescopic connection assembly 5 also includes an arm luffing cylinder 57, one end of the arm luffing cylinder 57 is hinged to the arm head 54, and the other end is hinged to the outer wall of the outer arm 51, so that the arm head 54, the outer arm 51 and the arm luffing cylinder 57 constitute a triangular luffing mechanism.

It should be noted that the jib head 54, outer arm 51, and telescopic transmission assembly 2 are articulated via a common pin 512; the first leveling cylinder 55, jib head 54, jib luffing cylinder 57, and outer arm 51 form a four-bar linkage. Furthermore, the first leveling cylinder 55 can be leveled electrically or hydraulically. When leveling electrically, the pin 512 that articulates the jib head 54, outer arm 51, and telescopic transmission assembly 2 is provided with an angle sensor (not shown) that facilitates matching with the first leveling cylinder 55. When leveling hydraulically, the telescopic transmission assembly 2 is provided with a hydraulic leveling device that matches the first leveling cylinder 55. Preferably, the first leveling cylinder 55 is leveled electrically.

The first leveling cylinder 55 pushes and pulls the arm head 54 to achieve leveling of the arm head 54. Specifically, the angle sensor installed on the arm head 54 presets a certain angle of the arm head 54 as zero. During the luffing process of the telescopic transmission assembly 2, the arm head 54 will tilt accordingly with the luffing of the telescopic transmission assembly 2. At this time, the angle sensor transmits the angle signal of the arm head 54 to the corresponding controller. After receiving the signal, the controller issues a corresponding control instruction to control the extension and retraction of the first leveling cylinder 55 to achieve leveling of the arm head 54, that is, to control the arm head 54 to always be at the preset zero position. In addition, the up and down luffing of the telescopic connection assembly 5 can be achieved by controlling the extension and retraction of the arm luffing cylinder 57.

Furthermore, a third leveling cylinder 58 is provided between the telescopic connection assembly 5 and the operating platform 3 . One end of the third leveling cylinder 58 is hinged to the inner arm 52 , and the other end is hinged to the swing cylinder 33 fixed to the operating platform 3 .

Preferably, a second leveling cylinder 56 is further provided between the jib head 54 and the telescopic connection assembly 5, one end of the second leveling cylinder 56 is hinged to the jib head 54, and the other end is hinged to the outer wall of the outer arm 51; the cavity of the second leveling cylinder 56 is connected to the cavity of the third leveling cylinder 58 through an oil pipe.

It should be noted that the arrangement of the second leveling cylinder 56 and the third leveling cylinder 58 can prevent the operating platform 3 from tilting during the boom length variation process of the telescopic connection assembly 5, and can ensure that the operating platform 3 always maintains a horizontal posture during the boom length variation process of the telescopic connection assembly 5. Therefore, the second leveling cylinder 56 and the third leveling cylinder 58 have a two-leveling function (the first leveling cylinder 55 and its related devices realize one-level leveling). Since the cavity of the second leveling cylinder 56 and the cavity of the third leveling cylinder 58 are connected through an oil pipe, the purpose of leveling can be achieved by the telescopic matching of the third leveling cylinder 58 and the second leveling cylinder 56. The specific process is as follows: when the telescopic connection assembly 5 varies upward, the telescopic rod in the arm boom length variation cylinder 57 extends, and at the same time, the telescopic rod in the second leveling cylinder 56 also extends. At this time, the hydraulic medium in the rod chamber of the second leveling cylinder 56 flows to the rod chamber of the third leveling cylinder 58 due to pressure, and then the extension of the third leveling cylinder 58 is completed. The retraction rod retracts, and the hydraulic medium in the rodless cavity of the third leveling cylinder 58 enters the rodless cavity of the second leveling cylinder 56 through the oil pipe, so as to achieve the leveling purpose by balancing the pressure in the relevant cavities of the third leveling cylinder 58 and the second leveling cylinder 56; when the telescopic connection assembly 5 changes amplitude downward, the same principle applies, except that the flow direction of the hydraulic medium and the movement state of the relevant components are opposite; wherein, the cylinder cross-sectional area, telescopic rod cross-sectional area and telescopic rod stroke of the second leveling cylinder 56 and the third leveling cylinder 58 are all preset and matched.

1 to 12 , which collectively illustrate a typical embodiment of a telescopic transmission assembly for an aerial work platform of the present invention, the telescopic transmission assembly 2 includes a base arm 21 , a second-section arm 22 , a third-section arm 23 , a telescopic cylinder 24 , a rope extension chain 27 , and a rope return chain 28 .

The two-section arm 22 is sleeved in the basic arm 21 and can be extended from the basic arm 21 (the upper side shown in Figure 7), and the three-section arm 23 is sleeved in the two-section arm 22 and can be extended from the extended end of the two-section arm 22 (the upper side shown in Figure 7).

The telescopic oil cylinder 24 includes a cylinder barrel 241 fixedly connected to the second-section arm 22 and a telescopic rod 242 sleeved in the cylinder barrel 241. The telescopic rod 242 has a hollow structure 247. The hollow structure 247 in the telescopic rod 242 is communicated with the internal cavity of the cylinder barrel 241. An oil guide pipe 245 is provided in the hollow structure 247 on the telescopic rod 242. The protruding end of the telescopic rod 242 (the lower side as shown in Figure 9) is fixedly connected to the basic arm 21. Preferably, the end face of the extended end of the telescopic rod 242 is fixed to the basic arm 21 through a clamping plate 8, and the cylinder 241 is provided with a connecting portion near the extended end of the telescopic rod 242 to facilitate the fixing of the cylinder 241 to the second-section arm 22. The connecting portion may include a pin shaft hole, that is, the pin shaft is inserted into the pin shaft hole to achieve the fixing of the cylinder 241 to the second-section arm 22; of course, the connecting portion on the cylinder 241 may also be provided at other positions of the cylinder 241, such as the middle part of the cylinder 241.

In addition, a first sprocket 25 is fixedly provided on the telescopic cylinder 24, and a second sprocket 26 is fixedly provided on the two-section arm 22. The second sprocket 26 is closer to the protruding end of the cylinder 241 than the first sprocket 25; one end of the telescopic chain 27 is fixedly connected to the basic arm 21, and the other end passes around the first sprocket 25 and is fixedly connected to the three-section arm 23, that is, both ends of the telescopic chain 27 are on the lower side of the first sprocket 25 (based on the direction of the relevant drawings in the specification); one end of the return rope chain 28 is fixedly connected to the three-section arm 23, and the other end passes around the second sprocket 26 and is fixedly connected to the basic arm 21, that is, both ends of the return rope chain 28 are on the upper side of the second sprocket 26 (based on the direction of the relevant drawings in the specification). Preferably, the first sprocket 25 is arranged on the telescopic cylinder 24 at the cylinder head at the end away from the extended end thereof, and the second sprocket 26 is arranged on the second-section arm 22 at the extended end near the telescopic rod 242; through this structural method, the first sprocket 25 and the second sprocket 26 can be respectively arranged at the upper and lower ends of the cylinder 241 (based on the direction of the relevant drawings in the accompanying drawings of the specification), which can ensure relatively smooth movement of the cylinder 241, thereby driving the smooth transmission and telescopic movement of related components; of course, the first sprocket 25 and the second sprocket 26 can also be set at other suitable positions, for example, the first sprocket 25 is arranged on the cylinder 241 near the middle of the cylinder, or the second sprocket 26 is arranged on the second-section arm 22 near the middle of the cylinder 241, etc.

11-12 , the internal cavity of the cylinder barrel 241 of the telescopic oil cylinder 24 is divided into a rod cavity 244 and a rodless cavity 243 by the telescopic rod 242, that is, the cavity formed by the overlapping portion of the internal cavity of the cylinder barrel 241 and the telescopic rod 242 is the rod cavity 244, and the portion of the internal cavity of the cylinder barrel 241 that does not overlap with the telescopic rod 242 and is located on the upper right side of the end of the telescopic rod 242 (based on the direction of FIG. 12 in the accompanying drawings of the specification) is the rodless cavity 243; the hollow structure 247 of the telescopic rod 242 is connected to the rod cavity 244 through a connecting channel 246; the hollow structure 247 of the telescopic rod 242 and the oil guide pipe 245 in the hollow structure 247 are both connected to an external oil pipe.

Furthermore, one end of each of the return chain 28 and the extension chain 27 is fixedly connected to the three-section boom 23 via a chain connector 29, with each end being fixedly connected to both sides of the chain connector 29. This structure facilitates the linkage between the extension chain 27, the return chain 28, and the three-section boom 23. Of course, the extension chain 27 and the return chain 28 can also be fixedly connected to the three-section boom 23 via different connecting components.

Furthermore, the extension chain 27 is provided with a chain detection device. This chain detection device can monitor the status of the relevant chain in real time. When the relevant chain breaks or exceeds a preset looseness value, it will issue an alarm signal, thereby ensuring the safe use of the telescopic transmission assembly 2 and, by extension, the personal safety of the operator and other relevant personnel. Specifically, the chain detection device can be provided at the end of the extension chain 27 connected to the base arm 21.

Preferably, the basic arm 21, the second-section arm 22 and the third-section arm 23 are all preferably hollow structures. Of course, the basic arm 21, the second-section arm 22 and the third-section arm 23 are not limited to being hollow structures inside, and they can also be other structures that can meet the above conditions.

Furthermore, the internal hollow structures of the basic arm 21, the second-section arm 22, and the third-section arm 23 form a telescopic cavity, and the telescopic cylinder 24, the first sprocket 25, the second sprocket 26, the extension chain 27, and the return chain 28 are all located within the telescopic cavity. This makes the structure of the telescopic transmission assembly 2 more compact, thereby reducing wear and aging of the relevant components, extending their service life, and reducing the frequency of repair and maintenance. It is also convenient and low-cost to repair and maintain these components. In addition, it can also reduce the risk of accidental injury to personnel due to the exposure of these components. Of course, it is also feasible to locate the telescopic cylinder 24, the first sprocket 25, the second sprocket 26, the extension chain 27, and the return chain 28 outside the telescopic cavity (i.e., on the outer walls of the basic arm 21, the second-section arm 22, and the third-section arm 23).

In summary, since the telescopic rod 242 is fixed on the basic arm 21, when the cylinder 241 is driven by an appropriate liquid medium, the cylinder 241 will drive the two-section arm 22 to move upward (based on the direction of the relevant drawings in the specification drawings), so that the two-section arm 22 extends from the upper end of the basic arm 21, and then the three-section arm 23 is pulled out from the upper end of the two-section arm 22 through the transmission action of the stretching chain 27 and the first sprocket 25. As the liquid medium is continuously input into the cylinder 241, the two-section arm 22 and the three-section arm 23 will continue to extend toward the upper end until the required moving stroke or the maximum preset stroke is reached; wherein, in this process, the first sprocket 25 is equivalent to a movable pulley, so that the displacement of the three-section arm 23 relative to the basic arm 21 is equal to 2 times the moving stroke of the cylinder 241 (that is, the displacement of the two-section arm 22 relative to the basic arm 21), which is convenient for increasing the telescopic stroke to a certain extent.

When oil is supplied to the rod chamber 244 in the cylinder 241 through the hollow structure 247 in the telescopic rod 242, the cylinder 241 will drive the second-section arm 22 to move downward together, so that the second-section arm 22 is retracted from the upper end of the basic arm 21, and then the three-section arm 23 is pulled back into the second-section arm 22 through the transmission action of the return rope chain 28 and the second sprocket 26. As oil continues to flow into the telescopic rod 242, the second-section arm 22 and the three-section arm 23 will continue to retract toward the lower end until the required retraction degree is reached or they are completely retracted into place; wherein, in this process, the second sprocket 26 is equivalent to a movable pulley, so that the displacement of the three-section arm 23 relative to the basic arm 21 is equal to twice the moving stroke of the cylinder 241 (that is, the displacement of the two-section arm 22 relative to the basic arm 21).

Specifically, referring to Figure 1 and other relevant drawings, the three-section arm 23 is hinged to the operating platform 3 through a telescopic connection assembly 5, that is, the three-section arm 23 is hinged to the outer arm 51 on the telescopic connection assembly 5, and the inner arm 52 on the telescopic connection assembly 5 is connected to the operating platform 3, and the telescopic connection assembly 5 facilitates the operating platform 3 to further extend and retract to a certain extent in the horizontal direction; the basic arm 21 is hinged to the vehicle body 1 through the support arm 4, that is, the basic arm 21 is hinged to the support arm 4, and the support arm 4 is movably connected to the relevant components on the vehicle body 1; in addition, a variable amplitude cylinder 6 is provided between the basic arm 21 and the support arm 4, which can make the basic arm 21, the support arm 4 and the variable amplitude cylinder 6 connected thereto also form a stable triangular structure, thereby making the aerial work platform have higher stability and safety during operation.

When the aerial work platform needs to raise its arm for operation, the second-section arm 22 and the third-section arm 23 in the telescopic transmission assembly 2 are controlled to extend. At this time, the operating platform 3 connected to the telescopic transmission assembly 2 will be synchronously extended under the drive of the third-section arm 23. At the same time, the relevant variable-length cylinder 6, support arm 4 and telescopic connection assembly 5 can also be controlled to adjust the extension angle or position of the relevant arm until the operating platform 3 reaches the preset working position or the maximum extension stroke.

Similarly, when the aerial work platform needs to retract its arms, the second-section arm 22 and the third-section arm 23 in the telescopic transmission assembly 2 are controlled to retract. At this time, the operating platform 3 connected to the telescopic transmission assembly 2 will be synchronously retracted under the drive of the third-section arm 23. At the same time, the relevant variable-length cylinder 6, support arm 4 and telescopic connection assembly 5 can also be controlled to adjust the angle or position of the relevant arms until the operating platform 3 retracts to the preset working position or the original unextended state.

In addition, please refer to Figure 13, which discloses another embodiment of the aerial work platform of the present invention. The difference between this embodiment and the above embodiment is that: the support member between the telescopic transmission assembly 2 and the telescopic connection assembly 5 is a variable amplitude cylinder 57, that is, the variable amplitude cylinder 57 is used to replace the first-level leveling related components in the above embodiment; the third leveling cylinder 58 adopts an electric leveling method, and the swing cylinder 33 is provided with an angle sensor 59 that cooperates with the third leveling cylinder 58, that is, the electric leveling method is used to replace the hydraulic leveling method in the second-level leveling in the above embodiment.

During operation, the telescopic connection assembly 5 can be moved up and down by extending and retracting the amplitude cylinder 57 between the telescopic transmission assembly 2 and the telescopic connection assembly 5; the operating table can be leveled by extending and retracting the third leveling cylinder 58 to ensure that the operating table is always in a horizontal state.

Specifically, the angle sensor 59 installed on the swing cylinder 33 presets a certain position of the operating platform 3 as the zero position. During the amplitude change process of the telescopic connection component 5, the angle sensor 59 will transmit an electrical signal to the corresponding controller. After receiving the signal, the controller will issue a corresponding control instruction to control the extension and retraction of the third leveling cylinder 58 to achieve the leveling of the operating platform, that is, to control the operating platform 3 to always be in the preset zero position.

In summary, the telescopic connection assembly in the present invention not only has a large horizontal extension, allowing the operating platform to extend to a farther area on the horizontal plane, thereby increasing the working range of the aerial work platform, but also has high structural strength and structural stability, which can greatly improve the safety of the aerial work platform.

Although some exemplary embodiments of the present invention have been shown above, it will be appreciated by those skilled in the art that changes may be made to these exemplary embodiments without departing from the principles or spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims (8)

1. A telescopic connection assembly for telescopically connecting a telescopic transmission assembly on an aerial work platform to an operating platform, characterized in that the telescopic connection assembly comprises: an outer arm, an inner arm slidably disposed in the outer arm and capable of extending from one end of the outer arm, and a forearm telescopic cylinder disposed between the outer arm and the inner arm; a forearm head is hinged to one end of the telescopic connection assembly connected to the telescopic transmission assembly; the telescopic connection assembly further comprises a forearm luffing cylinder, one end of which is hinged to the forearm head and the other end of which is hinged to the outer wall of the outer arm, such that the forearm head, the outer arm, and the forearm luffing cylinder form a triangular luffing mechanism; an angle sensor is installed on the forearm head for transmitting the angle signal of the forearm head to a corresponding controller, so that the forearm head is always kept at a preset zero position by the control of the controller; A first leveling cylinder is provided between the telescopic connecting assembly and the telescopic transmission assembly. One end of the first leveling cylinder is hinged to the telescopic transmission assembly, and the other end is hinged to the forearm head. 2. The telescopic connection assembly as claimed in claim 1, wherein the forearm telescopic cylinder includes a cylinder body and a piston rod slidably disposed in the cylinder body, the cylinder body is fixedly connected to the outer arm, and the extended end of the piston rod is fixedly connected to the inner arm. 3. The telescopic connection assembly as described in claim 2, wherein the cylinder is fixedly connected to the outer wall of the outer arm, and the extended end of the piston rod is fixedly connected to the outer wall of the inner arm. 4. An aerial work platform, characterized in that it comprises: a vehicle body, a telescopic transmission assembly, a telescopic connection assembly as described in any one of claims 1 to 3, and an operating platform connected sequentially; support members are provided between the vehicle body and the telescopic transmission assembly, and between the telescopic transmission assembly and the telescopic connection assembly. 5. The aerial work platform as described in claim 4, wherein the support component between the telescopic transmission assembly and the telescopic connection assembly is a variable amplitude hydraulic cylinder. 6. The aerial work platform as described in claim 4, characterized in that a third leveling cylinder is provided between the telescopic connecting assembly and the operating platform, one end of the third leveling cylinder is hinged to the inner arm, and the other end is hinged to a swing cylinder fixed to the operating platform. 7. The aerial work platform as described in claim 6, characterized in that the swing cylinder is provided with an angle sensor that cooperates with the third leveling cylinder. 8. The aerial work platform as described in claim 6, characterized in that a second leveling cylinder is further provided between the boom head and the telescopic connection assembly, one end of the second leveling cylinder is hinged to the boom head, and the other end is hinged to the outer wall of the outer boom; the cavity of the second leveling cylinder is connected to the cavity of the third leveling cylinder through an oil pipe.