Supporting leg telescopic structure and crane
By adopting a three-stage telescopic leg structure and a mechanical traction transmission mechanism in the crane leg structure, the problems of large internal space occupied by the legs, inconvenient assembly and maintenance and high costs in the existing technology are solved, and the effects of space saving, reliability improvement and cost reduction are achieved.
Patent Information
- Application Number
- CN202421457951.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-24
- Publication Date
- 2025-04-15
- Estimated Expiration
- 2034-06-24
AI Technical Summary
In the existing crane leg structure, the oil cylinder and related pipeline valve groups occupy most of the space inside the leg, affecting performance improvement, and inconvenient assembly and maintenance, and the cost is high.
A three-stage telescopic legs are adopted, in which the first, second and third-stage telescopic legs are driven by the first and second piston cylinders, and the three-stage telescopic legs are driven by the mechanical traction transmission mechanism under the driving of the second-stage telescopic legs.
Reduced the use of oil cylinders and related pipeline valve groups, save space, improve reliability and availability, reduce costs, and improve leg performance.
Smart Images
Figure CN222757833U_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the field of engineering machinery, and in particular to a leg telescopic structure and a crane. Background Art
[0002] The outrigger is one of the key components of the crane chassis and plays an important supporting role in the lifting operation of the whole vehicle. The larger the span of the outrigger, the better the lifting stability of the whole vehicle. At present, most crane outriggers adopt a single-section or double-section outrigger design. Due to the special arrangement requirements of the outrigger, the span of the double-section outrigger is limited. In order to increase the outrigger span, the outrigger is designed as a three-section outrigger structure. In some related technologies of the three-section outrigger structure, three cylinders are used to drive the three-stage outrigger to extend and retract respectively. Utility Model Content
[0003] The inventors have discovered through research that the three-section outrigger structure in the related art has the following main problems during actual application: the oil cylinder is located inside the outrigger box, and together with the matching pipelines and valve groups, it occupies most of the space inside the outrigger, which limits the internal reinforcement of the box and the design of other structures, affecting the improvement of the outrigger performance; the three oil cylinders plus the corresponding pipelines and valve groups occupy most of the space inside the outrigger, and the pipelines are prone to interference, wear and oil leakage during the extension and retraction process, affecting reliability, and are inconvenient to assemble and maintain; each outrigger requires three oil cylinders, plus the corresponding pipelines and valve groups, which is costly.
[0004] In view of this, the embodiments of the present disclosure provide a leg telescopic structure and a crane, which are beneficial to improving the performance of the legs.
[0005] In one aspect of the present disclosure, a leg telescopic structure is provided, comprising:
[0006] Fixed legs;
[0007] A first-stage telescopic leg, telescopically disposed within the fixed leg;
[0008] A secondary telescopic leg, telescopically disposed within the primary telescopic leg;
[0009] A third-stage telescopic leg, telescopically disposed within the second-stage telescopic leg;
[0010] A first piston cylinder, one end of which is fixedly connected to the fixed leg, and the other end of which is connected to the primary telescopic leg, and is configured to drive the primary telescopic leg to extend and retract relative to the fixed leg;
[0011] A second piston cylinder, one end of which is fixedly connected to the primary telescopic leg, and the other end of which is connected to the secondary telescopic leg, and is configured to drive the secondary telescopic leg to extend and retract relative to the primary telescopic leg; and
[0012] The mechanical traction transmission mechanism is arranged on the secondary telescopic leg and the tertiary telescopic leg, and is configured to drive the tertiary telescopic leg to extend and retract relative to the secondary telescopic leg by mechanical traction under the drive of the secondary telescopic leg.
[0013] In some embodiments, the mechanical traction transmission mechanism includes a guide rotating member and a traction member wrapped around the guide rotating member, the guide rotating member is arranged on the secondary telescopic leg, the traction member wraps around the guide rotating member, and both ends are respectively connected to the secondary telescopic leg and the tertiary telescopic leg.
[0014] In some embodiments, the mechanical traction transmission mechanism is a rope row transmission mechanism, the guide rotating member is a pulley group in the rope row transmission mechanism, and the traction member is a traction rope group in the rope row transmission mechanism.
[0015] In some embodiments, the pulley group includes a first pulley and a second pulley, the first pulley is arranged at the tail of the secondary telescopic leg, and the second pulley is arranged at the root of the secondary telescopic leg. The traction rope group includes a first traction rope and a second traction rope, one end of the first traction rope is fixedly connected to the root of the tertiary telescopic leg, and the other end is fixedly connected to the tail of the primary telescopic leg after passing around the first pulley; one end of the second traction rope is fixedly connected to the root of the tertiary telescopic leg, and the other end is fixedly connected to the tail of the primary telescopic leg after passing around the second pulley.
[0016] In some embodiments, the mechanical traction transmission mechanism is a chain sprocket transmission mechanism, the guide rotating member is a sprocket group in the chain sprocket transmission mechanism, and the traction member is a chain group in the chain sprocket transmission mechanism.
[0017] In some embodiments, the sprocket group includes a first sprocket and a second sprocket, the first sprocket is arranged at the tail of the secondary telescopic leg, and the second sprocket is arranged at the root of the secondary telescopic leg, the chain group includes a first chain and a second chain, one end of the first chain is fixedly connected to the root of the tertiary telescopic leg, and the other end is fixedly connected to the tail of the primary telescopic leg after bypassing the first sprocket, one end of the second chain is fixedly connected to the root of the tertiary telescopic leg, and the other end is fixedly connected to the tail of the primary telescopic leg after bypassing the second sprocket.
[0018] In some embodiments, one end of the traction member is connected to the first-stage telescopic leg via a screw with an adjustable length, and / or the other end of the traction member is connected to the third-stage telescopic leg via a screw with an adjustable length.
[0019] In some embodiments, the mechanical traction transmission mechanism is located at the lower side of the first piston cylinder and the second piston cylinder.
[0020] In some embodiments, the first piston cylinder and the second piston cylinder are configured to be retracted and extended synchronously or independently.
[0021] In some embodiments, the piston cylinder end of the first piston cylinder is fixedly connected to the root of the fixed leg, the cylinder barrel of the first piston cylinder is fixedly connected to the first telescopic leg and passes through the root of the second telescopic leg, and a first roller is provided inside the second telescopic leg to rollingly support the cylinder barrel of the first piston cylinder.
[0022] In some embodiments, the piston cylinder end of the second piston cylinder is fixedly connected to the root of the first-stage telescopic leg, the cylinder barrel of the second piston cylinder is fixedly connected to the second-stage telescopic leg and passes through the root of the third-stage telescopic leg, and a second roller is provided inside the third-stage telescopic leg to rollingly support the cylinder barrel of the second piston cylinder.
[0023] In some embodiments, the leg telescopic structure further comprises:
[0024] The vertical legs are arranged at the tail of the three-stage telescopic legs and are configured to achieve a supporting effect in the vertical direction.
[0025] In one aspect of the present disclosure, a crane is provided, comprising the aforementioned outrigger telescopic structure.
[0026] According to the disclosed embodiment, in the three-section telescopic leg structure, the first piston cylinder and the second piston cylinder are used to drive the first telescopic leg to telescope relative to the fixed leg and the second telescopic leg to telescope relative to the first telescopic leg, respectively, and a mechanical traction transmission mechanism is provided between the second telescopic leg and the third telescopic leg to drive the third telescopic leg to telescope relative to the second telescopic leg by mechanical traction under the drive of the second telescopic leg. Compared with the related art that drives the telescopic legs by three oil cylinders, this embodiment reduces the use of oil cylinders and related pipelines and valve groups by using a mechanical traction transmission mechanism, which is conducive to saving space, improving reliability and availability, reducing costs, and improving leg performance. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The accompanying drawings, which constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.
[0028] The present disclosure may be more clearly understood from the following detailed description with reference to the accompanying drawings, in which:
[0029] Figure 1is a schematic structural diagram of some embodiments of the outrigger telescopic structure disclosed in the present invention;
[0030] Figure 2 yes Figure 1 The illustrated embodiment is a schematic structural diagram in a fully retracted state.
[0031] It should be understood that the size of each part shown in the accompanying drawings is not drawn according to the actual proportional relationship. In addition, the same or similar reference numerals represent the same or similar components. DETAILED DESCRIPTION
[0032] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative and is in no way intended to limit the present disclosure and its application or use. The present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the present disclosure thorough and complete and to fully express the scope of the present disclosure to those skilled in the art. It should be noted that unless otherwise specifically stated, the relative arrangement of the components and steps, the composition of the materials, the numerical expressions and the numerical values set forth in these embodiments should be interpreted as being merely exemplary and not as limiting.
[0033] The words "first", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different parts. The words "include" or "comprise" and similar words mean that the elements before the word include the elements listed after the word, and do not exclude the possibility of including other elements. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.
[0034] In the present disclosure, when a specific device is described as being located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device. When a specific device is described as being connected to other devices, the specific device may be directly connected to the other device without an intermediate device, or may not be directly connected to the other device but have an intermediate device.
[0035] All terms (including technical terms or scientific terms) used in the present disclosure have the same meanings as those understood by ordinary technicians in the field to which the present disclosure belongs, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries, such as general dictionaries, should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an idealized or extremely formal sense, unless explicitly defined herein.
[0036] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.
[0037] In some related technologies of the three-section outrigger structure, three oil cylinders are used to drive the three-stage outrigger extension and retraction respectively. This three-section outrigger structure has the following main problems in actual application: the oil cylinder is located inside the outrigger box, and the matching pipelines and valve groups occupy most of the space inside the outrigger, which limits the internal reinforcement of the box and the design of other structures, affecting the improvement of the outrigger performance; the three oil cylinders plus the corresponding pipelines and valve groups occupy most of the space inside the outrigger, and the pipelines are prone to interference, wear and oil leakage during the extension and retraction process, affecting reliability, and it is inconvenient to assemble and maintain; each outrigger requires three oil cylinders, plus the corresponding pipelines and valve groups, which is costly.
[0038] In view of this, the embodiments of the present disclosure provide a leg telescopic structure and a crane, which are beneficial to improving the performance of the legs.
[0039] Figure 1 It is a schematic structural diagram of some embodiments of the telescopic structure of the legs disclosed in the present invention. Figure 2 yes Figure 1 The illustrated embodiment is a schematic diagram of the structure in a fully retracted state. Figure 1 and Figure 2 The embodiment of the present disclosure provides a telescopic structure of legs. The telescopic structure of legs includes: a fixed leg 10, a primary telescopic leg 21, a secondary telescopic leg 22, a tertiary telescopic leg 23, a first piston cylinder 31, a second piston cylinder 32 and a mechanical traction transmission mechanism 40.
[0040] The fixed support leg 10 can be installed on the body of the equipment to which the support leg telescopic structure is applied, for example, fixedly installed on the vehicle chassis of an engineering machinery vehicle.
[0041] The primary telescopic leg 21 is telescopically arranged in the fixed leg 10. The fixed leg 10 has an internal space, and the primary telescopic leg 21 is at least partially arranged in the internal space and can move in the internal space along the extension direction of the primary telescopic leg 21, thereby realizing extension or retraction relative to the internal space of the fixed leg 10.
[0042] The secondary telescopic leg 22 is telescopically arranged in the primary telescopic leg 21. The primary telescopic leg 21 has an internal space, and the secondary telescopic leg 22 is at least partially arranged in the internal space and can move in the internal space along the extension direction of the secondary telescopic leg 22, thereby realizing extension or retraction relative to the internal space of the primary telescopic leg 21.
[0043] The tertiary telescopic leg 23 is telescopically arranged in the secondary telescopic leg 22. The secondary telescopic leg 22 has an internal space, and the tertiary telescopic leg 23 is at least partially arranged in the internal space and can move in the internal space along the extension direction of the tertiary telescopic leg 23, thereby realizing extension or retraction relative to the internal space of the secondary telescopic leg 22.
[0044] In the extension direction of each level of telescopic legs, with the fixed leg 10 as a reference, the end adjacent to the fixed leg 10 is the root, and the end away from the fixed leg 10 is the tail. Figure 1 In the figure, the left end of the fixed leg 10 is the root of the fixed leg 10, and the right end is the tail of the fixed leg 10. The left end of each level of telescopic legs is the root, and the right end is the tail.
[0045] One end of the first piston cylinder 31 is fixedly connected to the fixed leg 10, and the other end is connected to the primary telescopic leg 21, and is configured to drive the primary telescopic leg 21 to extend and retract relative to the fixed leg 10. The first piston cylinder 31 can be a hydraulic cylinder or a gas cylinder, and the primary telescopic leg 21 is driven to extend and retract relative to the fixed leg 10 by the extension and retraction of the piston rod.
[0046] The second piston cylinder 32 has one end fixedly connected to the primary telescopic leg 21 and the other end connected to the secondary telescopic leg 22, and is configured to drive the secondary telescopic leg 22 to extend and retract relative to the primary telescopic leg 21. The second piston cylinder 32 may be a hydraulic cylinder or a gas cylinder, and the secondary telescopic leg 22 is driven to extend and retract relative to the primary telescopic leg 21 by the extension and retraction of the piston rod.
[0047] The mechanical traction transmission mechanism 40 is provided on the secondary telescopic leg 22 and the tertiary telescopic leg 23, and is configured to drive the tertiary telescopic leg 23 to extend and retract relative to the secondary telescopic leg 22 by mechanical traction under the drive of the secondary telescopic leg 22. The mechanical traction transmission mechanism 40 drives the tertiary telescopic leg 23 by the drive of the secondary telescopic leg 22 and the mechanical traction. Compared with the related art that drives the telescopic leg by three oil cylinders, the mechanical traction transmission mechanism can reduce the use of oil cylinders and related pipelines and valve groups, which is conducive to saving space, improving reliability and availability, reducing costs, and improving leg performance.
[0048] exist Figure 1 In the embodiment, the fixed leg 10, the first telescopic leg 21, the second telescopic leg 22 and the third telescopic leg 23 can be arranged horizontally, and the leg telescopic structure can also include a vertical leg 50, which can be arranged at the tail of the third telescopic leg 23 and is configured to achieve a supporting function in the vertical direction. The vertical leg 50 can include a leg, a bottom support part and a vertical piston cylinder.
[0049] In some embodiments, the mechanical traction transmission mechanism 40 includes a guide rotating member and a traction member wound around the guide rotating member, the guide rotating member is arranged on the secondary telescopic leg 22, the traction member winds around the guide rotating member, and the two ends of the traction member are respectively connected to the secondary telescopic leg 22 and the tertiary telescopic leg 23. The traction member cooperates with the guide rotating member to transmit the telescopic action of the secondary telescopic leg 22 to the tertiary telescopic leg 23 to drive the movement of the tertiary telescopic leg 23.
[0050] refer to Figure 1 and Figure 2 In some embodiments, the mechanical traction transmission mechanism 40 is a rope row transmission mechanism, the guide rotating member is a pulley group in the rope row transmission mechanism, and the traction member is a traction rope group in the rope row transmission mechanism.
[0051] Specifically, the pulley group may include a first pulley 41 and a second pulley 42, wherein the first pulley 41 is disposed at the tail of the secondary telescopic leg 22, and the second pulley 42 is disposed at the root of the secondary telescopic leg 22. The traction rope group may include a first traction rope 43 and a second traction rope 44, wherein one end of the first traction rope 43 is fixedly connected to the root of the tertiary telescopic leg 23, and the other end of the first traction rope 43 is fixedly connected to the tail of the primary telescopic leg 21 after passing through the first pulley 41. One end of the second traction rope 44 is fixedly connected to the root of the tertiary telescopic leg 23, and the other end of the second traction rope 44 is fixedly connected to the tail of the primary telescopic leg 21 after passing through the second pulley 42.
[0052] When the secondary telescopic leg 22 is extended or retracted, the first pulley 41 and the second pulley 42 fixedly connected to the secondary telescopic leg 22 are driven to move synchronously, and the first traction rope 43 and the second traction rope 44 are both connected to the tail of the primary telescopic leg 21 at one end and the root of the tertiary telescopic leg 23 at the other end, so that the tertiary telescopic leg 23 can be extended or retracted with a movement stroke twice that of the secondary telescopic leg 22. In addition, the two sets of traction ropes and pulleys can realize the driving effect of the mechanical traction transmission mechanism 40 on the tertiary telescopic leg 23 in the extension direction and the retraction direction.
[0053] refer to Figure 1 When the telescopic leg structure needs to be extended, the first piston cylinder 31 extends, driving the first-stage telescopic leg 21 to extend from the inside of the fixed leg 10; the second piston cylinder 32 extends, driving the second-stage telescopic leg 22 to extend from the inside of the first-stage telescopic leg 21, and at the same time drives the third-stage telescopic leg 23 to extend from the inside of the second-stage telescopic leg 22 through the rope transmission mechanism.
[0054] refer to Figure 2, which is the state where the telescopic structure of the legs is fully retracted. The first piston cylinder 31 contracts, driving the first telescopic leg 21 to contract into the fixed leg 10; the second piston cylinder 32 contracts, driving the second telescopic leg 22 to contract into the first telescopic leg 21, and at the same time driving the third telescopic leg 23 to contract into the second telescopic leg 22 through the rope transmission mechanism.
[0055] The first piston cylinder 31 and the second piston cylinder 32 can be configured to be synchronously retracted or independently retracted. The third-stage telescopic leg 23 and the second-stage telescopic leg 22 are connected by a rope transmission mechanism and are retracted synchronously.
[0056] In order to conveniently adjust the length of the traction member, in some embodiments, one end of the traction member is connected to the first-stage telescopic leg 21 through an adjustable-length screw 45, and / or the other end of the traction member is connected to the third-stage telescopic leg 23 through an adjustable-length screw 45.
[0057] In order to reduce the effect of gravity on the longer traction member in the mechanical traction transmission mechanism 40 sagging and affecting the extension and retraction of the three-stage telescopic legs, in some embodiments, the mechanical traction transmission mechanism 40 is located at the lower side of the first piston cylinder 31 and the second piston cylinder 32 .
[0058] refer to Figure 1 In some embodiments, the piston cylinder end 31r of the first piston cylinder 31 is fixedly connected to the root of the fixed leg 10, the cylinder barrel 31t of the first piston cylinder 31 is fixedly connected to the primary telescopic leg 21 and passes through the root of the secondary telescopic leg 22, and a first roller 221 for rolling support of the cylinder barrel 31t of the first piston cylinder 31 is provided inside the secondary telescopic leg 22. In this way, the first piston cylinder 31 can achieve stable rolling support for the cylinder barrel 31t of the first piston cylinder 31 through the first roller 221 during the telescopic process.
[0059] Similarly, reference Figure 1 In some embodiments, the piston cylinder end 32r of the second piston cylinder 32 is fixedly connected to the root of the first telescopic leg 21, the cylinder barrel 32t of the second piston cylinder 32 is fixedly connected to the second telescopic leg 22, and passes through the root of the third telescopic leg 23, and a second roller 231 for rolling support of the cylinder barrel 32t of the second piston cylinder 32 is provided inside the third telescopic leg 23. In this way, the second piston cylinder 32 can achieve stable rolling support for the cylinder barrel 32t of the second piston cylinder 32 through the second roller 231 during the telescopic process.
[0060] With reference to the rope transmission mechanism in the aforementioned embodiments, in other embodiments, the mechanical traction transmission mechanism 40 may be a chain sprocket transmission mechanism, the guide rotating member is a sprocket group in the chain sprocket transmission mechanism, and the traction member is a chain group in the chain sprocket transmission mechanism.
[0061] Specifically, please refer to Figure 1 and Figure 2 The rope row transmission mechanism shown in the figure is replaced by a sprocket wheel and a traction rope is replaced by a chain. That is, the sprocket wheel group includes a first sprocket wheel and a second sprocket wheel, the first sprocket wheel is arranged at the tail of the secondary telescopic leg 22, the second sprocket wheel is arranged at the root of the secondary telescopic leg 22, the chain group includes a first chain and a second chain, one end of the first chain is fixedly connected to the root of the tertiary telescopic leg 23, and the other end is fixedly connected to the tail of the primary telescopic leg 21 after passing through the first sprocket wheel, and one end of the second chain is fixedly connected to the root of the tertiary telescopic leg 23, and the other end is fixedly connected to the tail of the primary telescopic leg 21 after passing through the second sprocket wheel.
[0062] The various embodiments of the above-mentioned outrigger telescopic structure can be used for various engineering machinery equipment that need to use outriggers, such as cranes, concrete pump trucks, etc. In one aspect of the present disclosure, a crane is also provided, comprising the outrigger telescopic structure of any of the above-mentioned embodiments.
[0063] So far, various embodiments of the present disclosure have been described in detail. In order to avoid obscuring the concept of the present disclosure, some details known in the art are not described. Based on the above description, those skilled in the art can fully understand how to implement the technical solution disclosed here.
[0064] Although some specific embodiments of the present disclosure have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present disclosure. It should be understood by those skilled in the art that the above embodiments may be modified or some technical features may be replaced by equivalents without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.
Claims
1. A leg telescopic structure, characterized in that: include: Fixed legs (10); A first-stage telescopic support leg (21) telescopically arranged inside the fixed support leg (10); A secondary telescopic support leg (22) telescopically arranged inside the primary telescopic support leg (21); A third-stage telescopic support leg (23) telescopically arranged inside the second-stage telescopic support leg (22); A first piston cylinder (31), one end of which is fixedly connected to the fixed leg (10), and the other end of which is connected to the primary telescopic leg (21), and is configured to drive the primary telescopic leg (21) to telescope relative to the fixed leg (10); A second piston cylinder (32), one end of which is fixedly connected to the primary telescopic leg (21), and the other end of which is connected to the secondary telescopic leg (22), and is configured to drive the secondary telescopic leg (22) to telescope relative to the primary telescopic leg (21); and A mechanical traction transmission mechanism (40) is arranged on the secondary telescopic leg (22) and the tertiary telescopic leg (23), and is configured to drive the tertiary telescopic leg (23) to telescope relative to the secondary telescopic leg (22) by mechanical traction under the drive of the secondary telescopic leg (22).
2. The leg telescopic structure according to claim 1, characterized in that: The mechanical traction transmission mechanism (40) comprises a guide rotating member and a traction member wound around the guide rotating member, the guide rotating member being arranged on the secondary telescopic leg (22), the traction member winding around the guide rotating member, and two ends of the traction member being respectively connected to the secondary telescopic leg (22) and the tertiary telescopic leg (23).
3. The leg telescopic structure according to claim 2, characterized in that: The mechanical traction transmission mechanism (40) is a rope row transmission mechanism, the guide rotating member is a pulley group in the rope row transmission mechanism, and the traction member is a traction rope group in the rope row transmission mechanism.
4. The leg telescopic structure according to claim 3, characterized in that: The pulley group comprises a first pulley (41) and a second pulley (42), wherein the first pulley (41) is arranged at the tail of the secondary telescopic leg (22), and the second pulley (42) is arranged at the root of the secondary telescopic leg (22); the traction rope group comprises a first traction rope (43) and a second traction rope (44), wherein one end of the first traction rope (43) is fixedly connected to the root of the tertiary telescopic leg (23), and the other end is fixedly connected to the tail of the primary telescopic leg (21) after passing through the first pulley (41); and one end of the second traction rope (44) is fixedly connected to the root of the tertiary telescopic leg (23), and the other end is fixedly connected to the tail of the primary telescopic leg (21) after passing through the second pulley (42).
5. The leg telescopic structure according to claim 2, characterized in that: The mechanical traction transmission mechanism (40) is a chain sprocket transmission mechanism, the guide rotating member is a sprocket group in the chain sprocket transmission mechanism, and the traction member is a chain group in the chain sprocket transmission mechanism.
6. The leg telescopic structure according to claim 5, characterized in that: The sprocket group comprises a first sprocket and a second sprocket, the first sprocket being arranged at the tail of the secondary telescopic leg (22), the second sprocket being arranged at the root of the secondary telescopic leg (22), the chain group comprising a first chain and a second chain, one end of the first chain being fixedly connected to the root of the tertiary telescopic leg (23), the other end of the first chain being fixedly connected to the tail of the primary telescopic leg (21) after passing around the first sprocket, and one end of the second chain being fixedly connected to the root of the tertiary telescopic leg (23), the other end of the second chain being fixedly connected to the tail of the primary telescopic leg (21) after passing around the second sprocket.
7. The leg telescopic structure according to claim 2, characterized in that: One end of the traction member is connected to the first-stage telescopic leg (21) via a screw rod (45) with an adjustable length, and / or the other end of the traction member is connected to the third-stage telescopic leg (23) via a screw rod (45) with an adjustable length.
8. The leg telescopic structure according to claim 1, characterized in that: The mechanical traction transmission mechanism (40) is located at the lower side of the first piston cylinder (31) and the second piston cylinder (32).
9. The telescopic structure of legs according to claim 1, characterized in that: The first piston cylinder (31) and the second piston cylinder (32) are configured to be retracted synchronously or independently.
10. The leg telescopic structure according to claim 1, characterized in that: The piston cylinder end (31r) of the first piston cylinder (31) is fixedly connected to the root of the fixed leg (10), the cylinder barrel (31t) of the first piston cylinder (31) is fixedly connected to the first telescopic leg (21) and passes through the root of the second telescopic leg (22), and a first roller (221) for rolling support of the cylinder barrel (31t) of the first piston cylinder (31) is provided inside the second telescopic leg (22).
11. The telescopic structure of legs according to claim 1, characterized in that: The piston cylinder end (32r) of the second piston cylinder (32) is fixedly connected to the root of the first telescopic leg (21), the cylinder barrel (32t) of the second piston cylinder (32) is fixedly connected to the second telescopic leg (22) and passes through the root of the third telescopic leg (23), and a second roller (231) for rolling support of the cylinder barrel (32t) of the second piston cylinder (32) is provided inside the third telescopic leg (23).
12. The telescopic leg structure according to claim 1, characterized in that: Also includes: The vertical support leg (50) is arranged at the tail of the three-stage telescopic support leg (23) and is configured to achieve a supporting function in the vertical direction.
13. A crane, characterized in that: include: The telescopic leg structure according to any one of claims 1 to 12.