Leg telescopic structure and crane

Abstract

A leg telescopic structure and a crane. The leg telescopic structure comprises: a fixed leg (10); and a multi-stage telescopic leg (20), which is telescopically arranged in the fixed leg (10), the total length in the telescopic direction being adjusted by extending and retracting, wherein a lap-joint block matching structure is provided between adjacent stages of telescopic leg segments in the multi-stage telescopic leg (20); the lap-joint block matching structure comprises a first lap-joint block set (50) located on an outer surface (2o) of a web of an inner telescopic leg segment among the adjacent stages of telescopic leg segments and a second lap-joint block set (60) located on an inner surface (2i) of a web of an outer telescopic leg segment among the adjacent stages of telescopic leg segments; and the first lap-joint block set (50) and the second lap-joint block set (60) maintain lap-joint matching at any position between a maximum allowable extension position and a set extension position of the inner telescopic leg segment relative to the outer telescopic leg segment.

Description

Leg telescopic structure and crane

[0001] Cross-reference to related applications

[0002] This application is based on and claims priority to Chinese Patent Application No. 202410822809.6, filed on June 24, 2024, the disclosure of which is incorporated herein in its entirety. TECHNICAL FIELD

[0003] The present application relates to the field of engineering machinery, and in particular to a leg telescopic structure and a crane. BACKGROUND

[0004] The leg is one of the key components of the chassis of the crane, and plays an important supporting role in the lifting operation of the whole vehicle. The larger the span of the leg is, the better the lifting stability of the whole vehicle is. At present, in order to realize a larger span, the legs of some cranes adopt a double-section telescopic leg structure. In some related technologies, two inner lap blocks are arranged on the upright plate of the first-section movable leg, and three outer lap blocks are arranged on the upright plate of the last-section movable leg. The two inner lap blocks of the first-section movable leg lap and cooperate with one pair of adjacent outer lap blocks of the three outer lap blocks of the last-section movable leg when the last-section movable leg is in a full extension state, and lap and cooperate with another pair of adjacent outer lap blocks of the three outer lap blocks of the last-section movable leg when the last-section movable leg is in a half extension state. SUMMARY

[0005] The inventor has found through research that the double-section telescopic leg in the related technology cannot be telescoped to an arbitrary length, but can only be telescoped to a fixed length at the position where the inner and outer lap blocks lap and cooperate, and it is difficult to adaptively adjust the telescopic length of the leg according to the size of the construction range in actual engineering applications. Moreover, such a lap structure is only suitable for the telescoping of two-stage legs, and is difficult to support a larger leg span, and is not easy to meet the leg span requirements under a super large tonnage.

[0006] Therefore, the present application provides a leg telescopic structure and a crane, which is beneficial to improve the adaptability of the leg.

[0007] In one aspect of the present disclosure, a leg extension structure is provided, comprising: a fixed leg; and a multi-stage extension leg telescopically arranged in the fixed leg and adjustable in total length in a telescopic direction by extension; wherein a lapping block cooperation structure is arranged between adjacent stages of the multi-stage extension leg, the lapping block cooperation structure comprising a first lapping block group on an outer surface of a web of an inner extension leg of the adjacent stages and a second lapping block group on an inner surface of a web of an outer extension leg of the adjacent stages, the first lapping block group and the second lapping block group being cooperatively lapped at any position between a maximum allowed extension position and a set extension position of the inner extension leg relative to the outer extension leg.

[0008] In some embodiments, the first lapping block group comprises a rear lapping block and a first continuous lapping block group arranged in the telescopic direction, and the second lapping block group comprises a front lapping block and a second continuous lapping block group arranged in the telescopic direction, the rear lapping block being located at a position adjacent to a root of the web of the inner extension leg and cooperatively lapped with the second continuous lapping block group on the inner surface of the web of the outer extension leg, and the front lapping block being located at a position adjacent to a tail of the web of the outer extension leg and cooperatively lapped with the first continuous lapping block group on the outer surface of the web of the inner extension leg.

[0009] In some embodiments, the front lapping block is located on an upper side of the first continuous lapping block group, and the rear lapping block is located on an upper side of the second continuous lapping block group.

[0010] In some embodiments, the first continuous lapping block group is located between the rear lapping block and the tail of the inner extension leg, and has a first lapping range that is continuous in the telescopic direction, and a length of the first lapping range in the telescopic direction is greater than a length of the front lapping block in the telescopic direction.

[0011] In some embodiments, the first continuous lapping block group comprises: a first lapping block configured to cooperatively lap with the front lapping block when the inner extension leg is at the set extension position relative to the outer extension leg; a second lapping block configured to cooperatively lap with the front lapping block when the inner extension leg is at the maximum allowed extension position relative to the outer extension leg; and a first transition lapping block located between the first lapping block and the second lapping block, and two ends of the first transition lapping block in the telescopic direction are connected with the first lapping block and the second lapping block respectively, and a lapping surface of each of the first lapping block, the first transition lapping block and the second lapping block is flush with a lapping surface of the front lapping block.

[0012] In some embodiments, the set-out position is a position where the inner telescopic leg is set out half of a maximum stroke relative to the outer telescopic leg, and the allowed maximum set-out position is a position where the inner telescopic leg is set out the maximum stroke relative to the outer telescopic leg.

[0013] In some embodiments, the first and second lap blocks have a cross-sectional shape in a vertical direction of the outer surface of the web of the inner telescopic leg that is a closed figure, and the first transition lap block includes a first support bar extending in the telescoping direction and at least one first reinforcing rib disposed between the first support bar and the outer surface of the web of the inner telescopic leg.

[0014] In some embodiments, the front lap block is provided with a transition chamfer in the telescoping direction from a lap start position and / or a lap end position of the first continuous lap block group.

[0015] In some embodiments, the second continuous lap block group is located between the front lap block and the root of the outer telescopic leg and has a second continuous lap range in the telescoping direction, and a length of the second lap range in the telescoping direction is greater than a length of the rear lap block in the telescoping direction.

[0016] In some embodiments, the second continuous lap block group includes a third lap block configured to lap with the rear lap block when the inner telescopic leg is in the allowed maximum set-out position relative to the outer telescopic leg, and a second transition lap block located between the third lap block and the root of the outer telescopic leg and connected to the third lap block, and the third lap block and the second transition lap block each have a lapping surface that is flush with the rear lap block.

[0017] In some embodiments, the allowed maximum set-out position is a position where the inner telescopic leg is set out the maximum stroke relative to the outer telescopic leg.

[0018] In some embodiments, the third lap block has a cross-sectional shape in a vertical direction of the inner surface of the web of the outer telescopic leg that is a closed figure, and the second transition lap block includes a second support bar extending in the telescoping direction and at least one second reinforcing rib disposed between the second support bar and the outer surface of the web of the inner telescopic leg.

[0019] In some embodiments, the rear lap block is provided with a transition chamfer in the telescoping direction from a lap start position and / or a lap end position of the second continuous lap block group.

[0020] In some embodiments, the leg telescoping structure further comprises a telescoping driving mechanism for driving the telescoping of the multi-stage telescoping leg itself and the telescoping of the multi-stage telescoping leg relative to the fixed leg; wherein the telescoping driving mechanism comprises at least one piston cylinder.

[0021] In some embodiments, the multi-stage telescoping leg comprises a first-stage telescoping leg telescopically arranged in the fixed leg, a second-stage telescoping leg telescopically arranged in the first-stage telescoping leg, and a third-stage telescoping leg telescopically arranged in the second-stage telescoping leg; wherein the telescoping driving mechanism comprises a first piston cylinder having one end fixedly connected to the fixed leg and the other end connected to the first-stage telescoping leg and configured to drive the telescoping of the first-stage telescoping leg relative to the fixed leg, a second piston cylinder having one end fixedly connected to the first-stage telescoping leg and the other end connected to the second-stage telescoping leg and configured to drive the telescoping of the second-stage telescoping leg relative to the first-stage telescoping leg, and a mechanical traction transmission mechanism arranged in the second-stage telescoping leg and the third-stage telescoping leg and configured to drive the telescoping of the third-stage telescoping leg relative to the second-stage telescoping leg by mechanical traction under the driving of the second-stage telescoping leg.

[0022] In some embodiments, the mechanical traction transmission mechanism comprises a guide rotating member arranged on the second-stage telescoping leg and a traction member wound around the guide rotating member, and the two ends of the traction member are respectively connected to the second-stage telescoping leg and the third-stage telescoping leg.

[0023] In some embodiments, the mechanical traction transmission mechanism is a rope transmission mechanism, the guide rotating member is a pulley set in the rope transmission mechanism, and the traction member is a traction rope set in the rope transmission mechanism.

[0024] In some embodiments, the pulley set comprises a first pulley arranged at the tail of the second-stage telescoping leg and a second pulley arranged at the root of the second-stage telescoping leg, and the traction rope set comprises a first traction rope and a second traction rope, one end of the first traction rope is fixedly connected to the root of the third-stage telescoping leg, the other end of the first traction rope is fixedly connected to the tail of the first-stage telescoping leg after passing through the first pulley, one end of the second traction rope is fixedly connected to the root of the third-stage telescoping leg, and the other end of the second traction rope is fixedly connected to the tail of the first-stage telescoping leg after passing through the second pulley.

[0025] In some embodiments, the mechanical traction transmission mechanism is a chain and sprocket transmission mechanism, the guide rotating member is a sprocket set in the chain and sprocket transmission mechanism, and the traction member is a chain set in the chain and sprocket transmission mechanism.

[0026] In some embodiments, the chain wheel set comprises a first chain wheel and a second chain wheel, the first chain wheel is arranged at the tail of the second telescopic leg, the second chain wheel is arranged at the root of the second telescopic leg, the chain set comprises a first chain and a second chain, one end of the first chain is fixedly connected with the root of the third telescopic leg, the other end is fixedly connected with the tail of the first telescopic leg after passing through the first chain wheel, one end of the second chain is fixedly connected with the root of the third telescopic leg, the other end is fixedly connected with the tail of the first telescopic leg after passing through the second chain wheel.

[0027] In some embodiments, one end of the traction member is connected with the first telescopic leg through a screw rod with adjustable length, and / or the other end of the traction member is connected with the third telescopic leg through a screw rod with adjustable length.

[0028] In some embodiments, the mechanical traction transmission mechanism is located at the lower side of the first piston cylinder and the second piston cylinder.

[0029] In some embodiments, the first piston cylinder and the second piston cylinder are configured to be synchronously telescopic, independently telescopic or sequentially telescopic.

[0030] In some embodiments, the piston cylinder end of the first piston cylinder is fixedly connected with the root of the fixed leg, the cylinder barrel of the first piston cylinder is fixedly connected with the first telescopic leg and passes through the root of the second telescopic leg, and a first roller is arranged inside the second telescopic leg to rollingly support the cylinder barrel of the first piston cylinder.

[0031] In some embodiments, the piston cylinder end of the second piston cylinder is fixedly connected with the root of the first telescopic leg, the cylinder barrel of the second piston cylinder is fixedly connected with the second telescopic leg and passes through the root of the third telescopic leg, and a second roller is arranged inside the third telescopic leg to rollingly support the cylinder barrel of the second piston cylinder.

[0032] In some embodiments, the telescopic drive mechanism further comprises a hydraulic control system, the hydraulic control system comprising: a hydraulic pump, a hydraulic oil tank, a first directional valve, a throttle valve, a check valve, a second directional valve and a third directional valve, the hydraulic pump being in communication with an oil inlet of the first directional valve through an oil inlet oil line, the hydraulic oil tank being in communication with an oil return of the first directional valve through an oil return oil line, one working oil port of the first directional valve being in communication with rodless chambers of the first piston cylinder and the second piston cylinder, the other working oil port being in communication with rod chambers of the first piston cylinder and the second piston cylinder, the second directional valve being arranged on a hydraulic oil line between the first directional valve and the rodless chamber of the second piston cylinder, the third directional valve being arranged on a hydraulic oil line between the first directional valve and the rod chamber of the first piston cylinder, the throttle valve and the check valve being connected in parallel and connected in series on the hydraulic oil line between the first directional valve and the rod chamber of the first piston cylinder.

[0033] In some embodiments, the second directional valve and the third directional valve are both solenoid valves, the solenoid valves having a first working position and a second working position, and in the first working position, the connected oil line is bidirectional, and in the second working position, the connected oil line is unidirectional.

[0034] In some embodiments, the hydraulic control system further comprises: a drag chain mechanism for dragging the fixed leg to the hydraulic pipeline and the electrical harness of the second piston cylinder.

[0035] In some embodiments, the telescopic leg structure further comprises: a vertical leg arranged at the tail of the multi-stage telescopic leg and configured to realize a supporting effect in the vertical direction.

[0036] In one aspect of the present disclosure, a crane is provided, comprising the aforementioned telescopic leg structure.

[0037] According to the embodiments of the present disclosure, by arranging the overlapping block cooperation structure between adjacent telescopic legs in the multi-stage telescopic leg, and by overlapping cooperation between the first overlapping block group on the outer surface of the web plate of the inner telescopic leg and the second overlapping block group on the inner surface of the web plate of the outer telescopic leg in the overlapping block cooperation structure, the first overlapping block group and the second overlapping block group are kept in overlapping cooperation at any position between the maximum allowed extension position and the set extension position of the inner telescopic leg relative to the outer telescopic leg, which can adaptively adjust the telescopic length of the leg according to factors such as the size of the construction range in actual engineering application, and is conducive to supporting a larger adjustment range of the leg span, thereby improving the adaptability of the leg to various construction conditions. BRIEF DESCRIPTION OF DRAWINGS

[0038] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0039] The present disclosure can be more clearly understood with reference to the following detailed description together with the accompanying drawings, in which:

[0040] Fig. 1 is a schematic diagram of a mounting structure according to some embodiments of the outrigger telescoping structure of the present disclosure;

[0041] Fig. 2 is a schematic diagram of the internal structure of a primary telescoping outrigger according to some embodiments of the outrigger telescoping structure of the present disclosure;

[0042] Fig. 3 is a schematic diagram of the external structure of a secondary telescoping outrigger according to some embodiments of the outrigger telescoping structure of the present disclosure;

[0043] Fig. 4 is a schematic diagram of the internal structure of a secondary telescoping outrigger according to some embodiments of the outrigger telescoping structure of the present disclosure;

[0044] Fig. 5 is a schematic diagram of the external structure of a tertiary telescoping outrigger according to some embodiments of the outrigger telescoping structure of the present disclosure;

[0045] Fig. 6 is a schematic diagram of the engagement of a primary telescoping outrigger and a secondary telescoping outrigger when the secondary telescoping outrigger is in a maximum allowed extended position according to some embodiments of the outrigger telescoping structure of the present disclosure;

[0046] Fig. 7 is a schematic diagram of the engagement of a primary telescoping outrigger and a secondary telescoping outrigger when the secondary telescoping outrigger is in a position between a maximum allowed extended position and a set extended position according to some embodiments of the outrigger telescoping structure of the present disclosure;

[0047] Fig. 8 is a schematic diagram of the engagement of a secondary telescoping outrigger and a tertiary telescoping outrigger when the tertiary telescoping outrigger is in a maximum allowed extended position according to some embodiments of the outrigger telescoping structure of the present disclosure;

[0048] Fig. 9 is a schematic diagram of the engagement of a secondary telescoping outrigger and a tertiary telescoping outrigger when the tertiary telescoping outrigger is in a position between a maximum allowed extended position and a set extended position according to some embodiments of the outrigger telescoping structure of the present disclosure;

[0049] Fig. 10 is a schematic diagram of the internal structure of a tertiary telescoping outrigger and a telescoping drive mechanism according to some embodiments of the outrigger telescoping structure of the present disclosure;

[0050] Fig. 11 is a schematic diagram of the structure of the embodiment shown in Fig. 10 in a fully retracted state;

[0051] Fig. 12 is a schematic diagram of the hydraulic control principle of a first piston cylinder and a second piston cylinder according to some embodiments of the outrigger telescoping structure of the present disclosure;

[0052] FIG. 13 is a structural schematic diagram of the hydraulic control circuit configuration of FIG. 12 on a leg extension structure.

[0053] It should be understood that the dimensions of the various parts shown in the drawings are not drawn to scale. In addition, the same or similar reference numerals are used to represent the same or similar components.

[0054] BRIEF DESCRIPTION OF DRAWINGS: 10 - fixed leg; 20 - multi-stage extension leg; 2b - bottom plate; 2t - upper cover plate; 2o - outer surface of web; 2i - inner surface of web; 21 - first extension leg; 22 - second extension leg; 221 - first roller; 23 - third extension leg; 231 - second roller; 31 - first piston cylinder; 31r - piston cylinder end of first piston cylinder; 31t - cylinder tube of first piston cylinder; 32 - second piston cylinder; 32r - piston cylinder end of second piston cylinder; 32t - cylinder tube of second piston cylinder; 40 - mechanical traction transmission mechanism; 41 - first pulley; 42 - second pulley; 43 - first traction rope; 44 - second traction rope; 45 - screw rod; 50 - first set of overlapping blocks; 51 - rear overlapping block; 52 - first continuous set of overlapping blocks; 521 - first overlapping block; 522 - second overlapping block; 523 - first transition overlapping block; 523a - first support bar; 523b - first reinforcing rib; 60 - second set of overlapping blocks; 61 - front overlapping block; 62 - second continuous set of overlapping blocks; 621 - third overlapping block; 622 - second transition overlapping block; 622a - second support bar; 622b - second reinforcing rib; 71 - hydraulic pump; 72 - hydraulic oil tank; 73 - overflow valve; 74 - first directional valve; 75 - throttle valve; 76 - check valve; 77 - second directional valve; 78 - third directional valve; 79 - drag chain mechanism; 80 - vertical leg. DETAILED DESCRIPTION

[0055] 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 in nature and is in no way intended to limit the disclosure, its application or uses. The disclosure can be implemented in numerous different forms, as will be apparent to one of ordinary skill in the art. The embodiments provided are by way of example only, and nothing therein should be taken as a limitation upon the overall scope of the disclosure. It should be understood that the relative

[0056] The terms "first", "second", and similar terms used in the present disclosure do not denote any order, quantity, or importance, but are used to distinguish different parts. The terms "comprise", "include" or similar terms mean that the elements before the term encompass the elements listed after the term, and do not exclude the possibility of also encompassing other elements. "Up", "down", "left", "right", and the like are only used to indicate relative positional relationships, and when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0057] In the present disclosure, when it is described that a specific device is located between a first device and a second device, there can be an intervening device between the specific device and the first device or the second device, or there can be no intervening device. When it is described that a specific device is connected to another device, the specific device can be directly connected to the other device without an intervening device, or can not be directly connected to the other device with an intervening device.

[0058] All terms used in the present disclosure, including technical terms or scientific terms, have the same meaning as understood by a person of ordinary skill in the art to which the present disclosure belongs, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries should be interpreted to have meanings consistent with their meanings in the context of the relevant art, and should not be interpreted in an idealized or excessively formalized sense, unless otherwise defined explicitly herein.

[0059] Techniques, methods, and devices known to those of ordinary skill in the relevant art can not be discussed in detail, but should be considered part of the specification where appropriate.

[0060] In order to realize a larger span, some cranes use a double-section telescopic leg structure. In some related art, two inner lap blocks are arranged on the upright plate of the first-section movable leg, and three outer lap blocks are arranged on the upright plate of the last-section movable leg. The two inner lap blocks of the first-section movable leg lap and cooperate with one pair of adjacent outer lap blocks of the three outer lap blocks of the last-section movable leg when the last-section movable leg is in a fully extended state, and lap and cooperate with another pair of adjacent outer lap blocks of the three outer lap blocks of the last-section movable leg when the last-section movable leg is in a semi-extended state.

[0061] The inventor has found through research that the double-section telescopic leg in the related art cannot be telescoped to any length, but can only realize telescoping of a fixed length at the position where the inner and outer lap blocks lap and cooperate, and it is difficult to adaptively adjust the telescoping length of the leg according to the size of the construction range in actual engineering applications. Moreover, this lapping structure is only suitable for telescoping of two-stage legs, and is difficult to support a larger leg span, and is not easy to meet the leg span requirements under a super large tonnage.

[0062] Therefore, the present disclosure provides a support leg telescopic structure and a crane, which is beneficial to improve the adaptability of the support leg.

[0063] FIG. 1 is a schematic diagram of a mounting structure according to some embodiments of the support leg telescopic structure of the present disclosure. FIG. 2 is a schematic diagram of the internal structure of a first-stage telescopic support leg according to some embodiments of the support leg telescopic structure of the present disclosure. FIG. 3 is a schematic diagram of the external structure of a second-stage telescopic support leg according to some embodiments of the support leg telescopic structure of the present disclosure. FIG. 4 is a schematic diagram of the internal structure of the second-stage telescopic support leg according to some embodiments of the support leg telescopic structure of the present disclosure. FIG. 5 is a schematic diagram of the external structure of a third-stage telescopic support leg according to some embodiments of the support leg telescopic structure of the present disclosure.

[0064] Referring to FIGS. 1-5, the present disclosure provides a support leg telescopic structure, which includes a fixed support leg 10 and a multi-stage telescopic support leg 20. The fixed support leg 10 can be mounted on a device machine body to which the support leg telescopic structure is applied, for example, mounted on a vehicle chassis of a construction machinery vehicle.

[0065] The multi-stage telescopic support leg 20 is telescopically arranged in the fixed support leg 10 and adjusts the total length in the telescopic direction by telescoping. The multi-stage telescopic support leg 20 has at least two stages of telescopic support legs, and at least one set of adjacent two stages of telescopic support legs in the multi-stage telescopic support leg 20 can be relatively lengthened or shortened. The multi-stage telescopic support leg 20 can be partially arranged in the internal space of the fixed support leg 10 and can be integrally moved in the telescopic direction in the internal space, thereby realizing the extension or retraction of the multi-stage telescopic support leg 20 relative to the internal space of the fixed support leg 10.

[0066] The multi-stage telescopic support leg 20 is telescopically arranged in the fixed support leg 10 and adjusts the total length in the telescopic direction by telescoping. The multi-stage telescopic support leg 20 has at least two stages of telescopic support legs, and at least one set of adjacent two stages of telescopic support legs in the multi-stage telescopic support leg 20 can be relatively lengthened or shortened. The multi-stage telescopic support leg 20 can be partially arranged in the internal space of the fixed support leg 10 and can be integrally moved in the telescopic direction in the internal space, thereby realizing the extension or retraction of the multi-stage telescopic support leg 20 relative to the internal space of the fixed support leg 10.

[0067] For the multi-stage telescopic support leg 20, there can be one or more sets of adjacent stages of telescopic support legs according to the number of stages. For example, a two-stage telescopic support leg can include one set of adjacent stages of telescopic support legs, a three-stage telescopic support leg can include two sets of adjacent stages of telescopic support legs, and a four-stage telescopic support leg can include three sets of adjacent stages of telescopic support legs. The overlap block cooperation structure can be provided between part of the sets of adjacent stages of telescopic support legs or between all the sets of adjacent stages of telescopic support legs.

[0068] For one group of adjacent levels of telescopic legs, according to the sleeving relationship, the inner side telescopic leg and the outer side telescopic leg can be divided, and the inner side and the outer side are determined according to the relative position of the group of adjacent levels of telescopic legs. The inner side telescopic leg is telescopically arranged in the outer side telescopic leg.

[0069] Referring to FIG. 2, for the telescopic leg, it generally has an upper cover plate 2t, a bottom plate 2b and two webs, the upper cover plate 2t, the bottom plate 2b and the two webs together enclose a box structure, and the two webs are located between the upper cover plate 2t and the bottom plate 2b and are fixedly connected with the upper cover plate 2t and the bottom plate 2b respectively. The two webs can improve the bending resistance of the telescopic leg structure in the vertical direction and resist torsional deformation, thereby ensuring the straightness and overall stability of the arm section during telescoping. For the inner side telescopic leg, the web outer surface 2o refers to the outer surface of the web of the inner side telescopic leg adjacent to the side of the outer side telescopic leg. For the outer side telescopic leg, the web inner surface 2i refers to the outer surface of the web of the outer side telescopic leg adjacent to the side of the inner side telescopic leg.

[0070] The overlapping fit between the first set of overlapping blocks 50 and the second set of overlapping blocks 60 refers to the form of fit formed by the contact between the first set of overlapping blocks 50 and the second set of overlapping blocks 60, which includes the support in the vertical direction. The maximum allowed extension position of the inner side telescopic leg relative to the outer side telescopic leg can be the maximum limit extension position of the inner side telescopic leg relative to the outer side telescopic leg, or the maximum limit extension position within the allowed maximum extension position achieved by control or the like. The set extension position of the inner side telescopic leg relative to the outer side telescopic leg is the shortest extension position of the multi-level telescopic leg when the telescopic leg is in the support working condition. This shortest extension position can be the full retracted position of the inner side telescopic leg relative to the outer side telescopic leg, or a pre-set partially retracted position, such as 1 / 2, 1 / 4, 1 / 3, 2 / 3, 3 / 4, etc. times corresponding to the extension stroke of the maximum extension position.

[0071] In the present embodiment, by arranging the overlap block cooperation structure between adjacent levels of the multi-level telescopic support legs, the first overlap block group on the outer surface of the web plate of the inner telescopic support leg and the second overlap block group on the inner surface of the web plate of the outer telescopic support leg are overlapped and cooperated, so that the first overlap block group and the second overlap block group are overlapped and cooperated at any position between the maximum allowed extension position and the set extension position of the inner telescopic support leg relative to the outer telescopic support leg, so that the support telescopic support leg can continuously be in the support working condition at the maximum allowed extension position, the set extension position and any position between them of the inner telescopic support leg relative to the outer telescopic support leg, thereby adapting the telescopic length of the support legs according to factors such as the size of the construction range in actual engineering application, and facilitating the support of a larger adjustment range of the support leg span, thereby improving the adaptability of the support legs to various construction conditions.

[0072] A support telescopic structure comprising three levels of telescopic support legs is shown in FIG. 1, wherein a first level telescopic support leg 21 is telescopically arranged in the fixed support leg 10, a second level telescopic support leg 22 is telescopically arranged in the first level telescopic support leg 21, and a third level telescopic support leg 23 is telescopically arranged in the second level telescopic support leg 22.

[0073] FIGS. 2 and 3 respectively show the structure of the second overlap block group 60 arranged on the inner surface 2i of the web plate of the first level telescopic support leg 21 and the structure of the first overlap block group 50 arranged on the outer surface 2o of the web plate of the second level telescopic support leg 22. FIGS. 4 and 5 respectively show the structure of the second overlap block group 60 arranged on the inner surface 2i of the web plate of the second level telescopic support leg 22 and the structure of the first overlap block group 50 arranged on the outer surface 2o of the web plate of the third level telescopic support leg 23. As can be seen in the figures, the first overlap block group 50 and the second overlap block group 60 can be arranged on both web plates. In other embodiments, the first overlap block group 50 and the second overlap block group 60 can be arranged on only one of the two web plates.

[0074] Referring to FIGS. 2-5, in some embodiments, the first overlap block group 50 comprises a rear overlap block 51 and a first continuous overlap block group 52 arranged in the telescopic direction, and the second overlap block group 60 comprises a front overlap block 61 and a second continuous overlap block group 62 arranged in the telescopic direction, the rear overlap block 51 is located at a position adjacent to the root of the outer surface 2o of the web plate of the inner telescopic support leg, and is overlapped and cooperated with the second continuous overlap block group 62 on the inner surface 2i of the web plate of the outer telescopic support leg, the front overlap block 61 is located at a position adjacent to the tail of the inner surface 2i of the web plate of the outer telescopic support leg, and is overlapped and cooperated with the first continuous overlap block group 52 on the outer surface 2o of the web plate of the inner telescopic support leg.

[0075] Here, the root and the tail are relative to the fixed leg 10. The end of the telescopic leg adjacent to one side of the fixed leg 10 is the root of the telescopic leg, and the end away from the fixed leg 10 is the tail of the telescopic leg. Generally, for adjacent telescopic legs, the root of the inner telescopic leg is located in the inner space of the outer telescopic leg, and the tail extends out of the inner space of the outer telescopic leg.

[0076] The overlapping matching relationship formed by the front overlapping block 61 and the first continuous overlapping block group 52 and the overlapping matching relationship formed by the rear overlapping block 51 and the second continuous overlapping block group 62 can form two groups of overlapping matching relationships between the inner telescopic leg and the outer telescopic leg in the telescopic direction of the telescopic leg, ensure the reliability and continuity of the overlapping matching, and make the stress between the inner telescopic leg and the outer telescopic leg more balanced.

[0077] In FIGS. 2-5, the front overlapping block 61 can be located on the upper side of the first continuous overlapping block group 52, and the rear overlapping block 51 can be located on the upper side of the second continuous overlapping block group 62. In this way, the two groups of overlapping matching relationships will not interfere with each other, and the spatial arrangement is also more convenient.

[0078] FIG. 6 is a schematic diagram of the overlapping matching of the first telescopic leg and the second telescopic leg in some embodiments of the telescopic leg structure according to the present disclosure when the second telescopic leg is in the allowed maximum extended position. FIG. 7 is a schematic diagram of the overlapping matching of the first telescopic leg and the second telescopic leg in some embodiments of the telescopic leg structure according to the present disclosure when the second telescopic leg is in a position between the allowed maximum extended position and the set extended position. FIG. 8 is a schematic diagram of the overlapping matching of the second telescopic leg and the third telescopic leg in some embodiments of the telescopic leg structure according to the present disclosure when the third telescopic leg is in the allowed maximum extended position. FIG. 9 is a schematic diagram of the overlapping matching of the second telescopic leg and the third telescopic leg in some embodiments of the telescopic leg structure according to the present disclosure when the third telescopic leg is in a position between the allowed maximum extended position and the set extended position.

[0079] Referring to FIGS. 6-9, in some embodiments, the first continuous overlapping block group 52 is located between the rear overlapping block 51 and the tail of the inner telescopic leg, and has a first overlapping range that is continuous in the telescopic direction, and the length of the first overlapping range in the telescopic direction is greater than the length of the front overlapping block 61 in the telescopic direction.

[0080] As can be seen in FIGS. 6-9, the first continuous overlapping block group 52 is relatively long in the telescopic direction, and the front overlapping block 61 can overlap with multiple positions of the first continuous overlapping block group 52 in the telescopic direction to match different telescopic leg lengths.

[0081] In some embodiments, the second continuous overlap block group 62 is located between the front overlap block 61 and the root of the outer side telescopic leg, and has a second overlap range continuous in the telescopic direction, the length of the second overlap range in the telescopic direction is greater than the length of the rear overlap block 51 in the telescopic direction.

[0082] It can be seen that the second continuous overlap block group 62 is longer in the telescopic direction, and the rear overlap block 51 can be overlapped with multiple positions of the second continuous overlap block group 62 in the telescopic direction to match different leg telescopic lengths.

[0083] Referring to FIGS. 3 and 5-9, in some embodiments, the first continuous overlap block group 52 includes a first overlap block 521, a second overlap block 522, and a first transition overlap block 523. The first overlap block 521 is configured to be overlapped with the front overlap block 61 when the inner side telescopic leg is in the set extended position relative to the outer side telescopic leg. The second overlap block 522 is configured to be overlapped with the front overlap block 61 when the inner side telescopic leg is in the allowed maximum extended position relative to the outer side telescopic leg.

[0084] Here, the allowed maximum extended position can be but is not limited to the position where the inner side telescopic leg is extended by the maximum stroke relative to the outer side telescopic leg. When the allowed maximum extended position is set to the position where the inner side telescopic leg is extended by the maximum stroke relative to the outer side telescopic leg (i.e., the position where the inner side telescopic leg is fully extended relative to the outer side telescopic leg), a farther and larger range of leg span can be achieved. The set extended position can be but is not limited to the position where the inner side telescopic leg is extended by N times the maximum stroke relative to the outer side telescopic leg, N satisfying 0≤N≤3 / 4. When N is 0, it is equivalent to the set extended position being the position where the inner side telescopic leg is fully retracted relative to the outer side telescopic leg. N can be 1 / 4, 1 / 3, 1 / 2, 2 / 3, 3 / 4, etc. according to the actual application scenario of the telescopic leg structure applied to the engineering vehicle.

[0085] The first transition overlap block 523 is located between the first overlap block 521 and the second overlap block 522, and the two ends of the first transition overlap block 523 in the telescopic direction are connected with the first overlap block 521 and the second overlap block 522 respectively, and the overlap faces of the first overlap block 521, the first transition overlap block 523, and the second overlap block 522 for overlapping with the front overlap block 61 are flush.

[0086] Since the first lap block 521, the first transition lap block 523 and the second lap block 522 are flush with the lap surface for lap fitting with the front lap block 61 respectively, the front lap block 61 can be very smooth when sliding from one lap block to the adjacent lap block among the first lap block 521, the first transition lap block 523 and the second lap block 522, so as to reduce or eliminate the shock during the stretching and contracting action.

[0087] Referring to FIG. 3 and FIG. 5, in some embodiments, the first lap block 521 and the second lap block 522 have a cross-sectional shape of a closed figure with a hole in the vertical direction of the web outer surface 2o of the inner side stretching leg, for example, a rectangular protrusion with an oblong hole as shown in FIG. 3 and FIG. 5. The cross-sectional shape of such a figure can make the first lap block 521 and the second lap block 522 when welded on the web outer surface 2o, the weld can be formed on the outer edge of the rectangular protrusion and the inner edge of the oblong hole, so as to achieve a larger range of weld, which is conducive to improving the connection strength.

[0088] The first lap block 521 and the second lap block 522 as two end points of the continuous lap range will be more used for supporting working conditions in general, so the above structure is conducive to improving the lap reliability. The first transition lap block 523 includes a first support bar 523a extending in the stretching direction and at least one first reinforcing rib 523b arranged between the first support bar 523a and the web outer surface 2o of the inner side stretching leg. Such a structure not only forms a continuous lap fitting surface through the first support bar 523a, but also achieves the reinforcing effect through the first reinforcing rib 523b, and compared with the cross-sectional shape of the closed figure, the first transition lap block 523 consumes less material and weighs less.

[0089] In order to enable the front lap block 61 to smoothly enter or exit the lap starting position and / or the lap ending position relative to the first continuous lap block group 52, improve the smoothness of the leg stretching and contracting, and reduce the risk of jamming, in some embodiments, the front lap block 61 is provided with a transition chamfer in the stretching direction relative to the lap starting position and / or the lap ending position of the first continuous lap block group 52. The contact surface can be machined and / or smeared with grease as needed to ensure the smoothness of the contact surface movement.

[0090] Referring to FIG. 2, FIG. 4, FIG. 6-FIG. 9, in some embodiments, the second continuous lapping block group 62 comprises: a third lapping block 621 and a second transition lapping block 622. The third lapping block 621 is configured to lap with the rear lapping block 51 when the inner side retractable leg is in the allowed maximum extended position relative to the outer side retractable leg. The second transition lapping block 622 is located between the third lapping block 621 and the root of the outer side retractable leg, and is connected with the third lapping block 621, and the lapping surfaces of the third lapping block 621 and the second transition lapping block 622 are flush for lapping with the rear lapping block 51.

[0091] Here, the allowed maximum extended position can be, but is not limited to, the position where the inner side retractable leg is extended to the maximum stroke relative to the outer side retractable leg. When the allowed maximum extended position is set to the position where the inner side retractable leg is extended to the maximum stroke relative to the outer side retractable leg (i.e., the position where the inner side retractable leg is fully extended relative to the outer side retractable leg), a farther and larger range of leg span can be achieved.

[0092] Since the lapping surfaces of the third lapping block 621 and the second transition lapping block 622 are flush for lapping with the rear lapping block 51, the rear lapping block 51 can slide very smoothly between the third lapping block 621 and the second transition lapping block 622, so as to reduce or eliminate the shock during the retracting and extending action.

[0093] Referring to FIG. 2 and FIG. 4, in some embodiments, the cross-sectional shape of the third lapping block 621 in the vertical direction of the inner surface 2i of the web of the outer side retractable leg is a closed figure with a hole, such as a rectangular protrusion with a long circular hole as shown in FIG. 2 and FIG. 4. The cross-sectional shape of such a figure can make the welding seam formed on the outer edge of the rectangular protrusion and the inner edge of the long circular hole when the third lapping block 621 is welded on the inner surface 2i of the web, so as to achieve a larger range of welding seam, which is conducive to improving the connection strength.

[0094] The third lapping block 621 as an end point of the continuous lapping range is usually more used for supporting working conditions, so the above structure is conducive to improving the lapping reliability. The second transition lapping block 622 comprises a second support strip 622a extending in the retracting direction and at least one second reinforcing rib 622b arranged between the second support strip 622a and the outer surface 2o of the web of the inner side retractable leg. Such a structure not only forms a continuous lapping surface through the second support strip 622a, but also achieves a reinforcing effect through the second reinforcing rib 622b, and compared with the closed figure cross-sectional shape, the second transition lapping block 622 consumes less material and weighs less.

[0095] In order to enable the rear lapping block 51 to enter or exit the lapping start position and / or the lapping end position relative to the second continuous lapping block group 62 smoothly, improve the smoothness of the leg extension and retraction, and reduce the risk of jamming, in some embodiments, the rear lapping block 51 is provided with a transition chamfer in the extension and retraction direction relative to the lapping start position and / or the lapping end position of the second continuous lapping block group 62. The contact surface can also be machined or / and smeared with lubricating grease as needed to ensure the smoothness of the contact surface movement.

[0096] Figure 10 is a schematic diagram of the internal structure of a three-stage extension and retraction leg and an extension and retraction driving mechanism in some embodiments of the leg extension and retraction structure according to the present disclosure. Figure 11 is a schematic diagram of the structure of the embodiment shown in Figure 10 in a fully retracted state.

[0097] In order to realize the extension and retraction operation of the leg extension and retraction structure, in some embodiments, the leg extension and retraction structure further comprises an extension and retraction driving mechanism. The extension and retraction driving mechanism is used to drive the extension and retraction of the multi-stage extension and retraction leg 20 itself and the extension and retraction of the multi-stage extension and retraction leg 20 relative to the fixed leg 10. Here, the extension and retraction driving mechanism comprises at least one stage of a piston cylinder. For example, the extension and retraction driving mechanism comprises a single stage of a piston cylinder, or comprises two or more stages of a piston cylinder. The piston cylinder can be driven by hydraulic oil, or can be driven by pneumatic or electric means.

[0098] According to the above embodiments of the leg extension and retraction structure, the relative extension and retraction lengths of the multi-stage extension and retraction leg and the extension and retraction driving mechanism cooperate with each other to realize more kinds of extension and retraction lengths, and meet the working conditions of various leg spans.

[0099] Referring to Figures 10 and 11, in some embodiments, the multi-stage extension and retraction leg 20 comprises a first-stage extension and retraction leg 21, a second-stage extension and retraction leg 22, and a third-stage extension and retraction leg 23. The extension and retraction driving mechanism comprises a first piston cylinder 31, a second piston cylinder 32, and a mechanical traction transmission mechanism 40.

[0100] The first-stage extension and retraction leg 21 is telescopically arranged in the fixed leg 10. The fixed leg 10 has an internal space, and the first-stage extension and retraction leg 21 is at least partially arranged in the internal space and can move in the extension direction of the first-stage extension and retraction leg 21 within the internal space, thereby realizing extension or retraction relative to the internal space of the fixed leg 10.

[0101] The second-stage extension and retraction leg 22 is telescopically arranged in the first-stage extension and retraction leg 21. The first-stage extension and retraction leg 21 has an internal space, and the second-stage extension and retraction leg 22 is at least partially arranged in the internal space and can move in the extension direction of the second-stage extension and retraction leg 22 within the internal space, thereby realizing extension or retraction relative to the internal space of the first-stage extension and retraction leg 21.

[0102] The third telescopic leg 23 is telescopically arranged in the second telescopic leg 22. The second telescopic leg 22 has an inner space, and the third telescopic leg 23 is at least partially arranged in the inner space of the second telescopic leg 22 and is movable in the extension direction of the third telescopic leg 23 in the inner space of the second telescopic leg 22, so as to realize extension or retraction relative to the inner space of the second telescopic leg 22.

[0103] The first piston cylinder 31 is fixedly connected to one end of the fixed leg 10 and connected to the other end of the first telescopic leg 21, and is configured to drive the first telescopic leg 21 to telescopically extend or retract relative to the fixed leg 10. The first piston cylinder 31 can be a hydraulic cylinder or an air cylinder, and the telescopic extension or retraction of the first piston cylinder 31 drives the telescopic extension or retraction of the first telescopic leg 21 relative to the fixed leg 10.

[0104] The second piston cylinder 32 is fixedly connected to one end of the first telescopic leg 21 and connected to the other end of the second telescopic leg 22, and is configured to drive the second telescopic leg 22 to telescopically extend or retract relative to the first telescopic leg 21. The second piston cylinder 32 can be a hydraulic cylinder or an air cylinder, and the telescopic extension or retraction of the second piston cylinder 32 drives the telescopic extension or retraction of the second telescopic leg 22 relative to the first telescopic leg 21.

[0105] The mechanical traction transmission mechanism 40 is arranged on the second telescopic leg 22 and the third telescopic leg 23, and is configured to drive the third telescopic leg 23 to telescopically extend or retract relative to the second telescopic leg 22 by mechanical traction under the driving of the second telescopic leg 22. The mechanical traction transmission mechanism 40 drives the third telescopic leg 23 by mechanical traction under the driving of the second telescopic leg 22, compared with the prior art which drives the telescopic leg by three oil cylinders, the mechanical traction transmission mechanism can reduce the use of oil cylinders, related pipelines and valve groups, which is beneficial to save space, improve reliability and usability, reduce cost and improve leg performance.

[0106] 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 second telescopic leg 22, the traction member is wound around the guide rotating member, and the two ends of the traction member are respectively connected to the second telescopic leg 22 and the third telescopic leg 23.

[0107] The second telescopic leg 22 and the third telescopic leg 23 are connected. The traction member cooperates with the guide rotating member to enable the telescopic action of the second telescopic leg 22 to be transmitted to the third telescopic leg 23 to drive the movement of the third telescopic leg 23.

[0108] Referring to FIGS. 10 and 11, in some embodiments, the mechanical traction transmission mechanism 40 is a rope transmission mechanism, the guide rotating member is a pulley set in the rope transmission mechanism, and the traction member is a traction rope set in the rope transmission mechanism.

[0109] Specifically, the pulley block can include a first pulley 41 arranged at the tail of the second telescopic leg 22 and a second pulley 42 arranged at the root of the second telescopic leg 22. The traction rope block can include a first traction rope 43 and a second traction rope 44. One end of the first traction rope 43 is fixedly connected to the root of the third telescopic leg 23, and the other end is fixedly connected to the tail of the first 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 third telescopic leg 23, and the other end is fixedly connected to the tail of the first telescopic leg 21 after passing through the second pulley 42.

[0110] When the second telescopic leg 22 is telescoped, the first pulley 41 and the second pulley 42 fixedly connected to the second telescopic leg 22 are synchronously moved, and the first traction rope 43 and the second traction rope 44 are both connected at one end to the tail of the first telescopic leg 21 and at the other end to the root of the third telescopic leg 23, so that the third telescopic leg 23 can be telescoped at twice the movement stroke of the second telescopic leg 22. Moreover, the setting of the two groups of traction ropes and pulleys can realize the driving effect of the mechanical traction type transmission mechanism 40 on the third telescopic leg 23 in the extension direction and the retraction direction.

[0111] Referring to FIG. 10, when it is necessary to extend the telescopic leg structure, the first piston cylinder 31 is elongated to drive the first telescopic leg 21 to extend from the inside of the fixed leg 10; the second piston cylinder 32 is elongated to drive the second telescopic leg 22 to extend from the inside of the first telescopic leg 21, and simultaneously drive the third telescopic leg 23 to extend from the inside of the second telescopic leg 22 through the rope block transmission mechanism.

[0112] Referring to FIG. 11, the first piston cylinder 31 is retracted to drive the first telescopic leg 21 to retract into the fixed leg 10; the second piston cylinder 32 is retracted to drive the second telescopic leg 22 to retract into the first telescopic leg 21, and simultaneously drive the third telescopic leg 23 to retract into the second telescopic leg 22 through the rope block transmission mechanism.

[0113] The first piston cylinder 31 and the second piston cylinder 32 can be configured to be synchronously telescoped, independently telescoped, or sequentially telescoped. The third telescopic leg 23 and the second telescopic leg 22 are synchronously retracted through the connection of the rope block transmission mechanism.

[0114] 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 telescopic leg 21 through a screw rod 45 with adjustable length, and / or the other end of the traction member is connected to the third telescopic leg 23 through a screw rod 45 with adjustable length.

[0115] In order to reduce the influence of the longer traction member in the mechanical traction transmission mechanism 40 under the action of gravity on the extension and retraction of the third telescopic leg, in some embodiments, the mechanical traction transmission mechanism 40 is located on the lower side of the first piston cylinder 31 and the second piston cylinder 32.

[0116] Referring to FIG. 10, 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 first telescopic leg 21 and passes through the root of the second telescopic leg 22, and the first telescopic leg 22 is internally provided with a first roller 221 for rollably supporting the cylinder barrel 31t of the first piston cylinder 31. In this way, the first piston cylinder 31 can be stably rollably supported by the first roller 221 during the extension and retraction of the first piston cylinder 31.

[0117] Similarly, referring to FIG. 10, 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 the third telescopic leg 23 is internally provided with a second roller 231 for rollably supporting the cylinder barrel 32t of the second piston cylinder 32. In this way, the second piston cylinder 32 can be stably rollably supported by the second roller 231 during the extension and retraction of the second piston cylinder 32.

[0118] Referring to the rope transmission mechanism in the foregoing embodiments, in other embodiments, the mechanical traction transmission mechanism 40 can be a chain and sprocket transmission mechanism, the guide rotating member is a sprocket set of the chain and sprocket transmission mechanism, and the traction member is a chain set of the chain and sprocket transmission mechanism.

[0119] Specifically, referring to the rope transmission mechanism shown in FIGS. 10 and 11, the pulley is replaced by a sprocket, and the traction rope is replaced by a chain. That is, the sprocket set includes a first sprocket and a second sprocket, the first sprocket is arranged at the tail of the second telescopic leg 22, the second sprocket is arranged at the root of the second telescopic leg 22, the chain set includes a first chain and a second chain, one end of the first chain is fixedly connected to the root of the third telescopic leg 23, the other end of the first chain is fixedly connected to the tail of the first telescopic leg 21 after passing around the first sprocket, one end of the second chain is fixedly connected to the root of the third telescopic leg 23, and the other end of the second chain is fixedly connected to the tail of the first telescopic leg 21 after passing around the second sprocket.

[0120] Referring to FIGS. 1, 10 and 11, in some embodiments, the leg telescopic structure further comprises a vertical leg 80. The vertical leg 80 is arranged at the tail of the multi-stage telescopic leg 20 and is configured to realize the supporting effect in the vertical direction. The vertical leg 80 can comprise a leg, a bottom support part and a vertical piston cylinder. The vertical leg 80 can realize stable support of the bottom support part to the ground through the extension of the vertical piston cylinder, and realize the recovery of the vertical leg 80 through the retraction of the vertical piston cylinder, thereby reducing the occupied space. The fixed leg 10, the first-stage telescopic leg 21, the second-stage telescopic leg 22 and the third-stage telescopic leg 23 can be arranged horizontally, while the vertical leg 80 is arranged vertically, thereby forming a stable and reliable L-shaped support structure.

[0121] Referring to FIGS. 10 and 11, 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, and the cylinder barrel 31t of the first piston cylinder 31 is fixedly connected to the first-stage telescopic leg 21 and passes through the root of the second-stage telescopic leg 22, and the first-stage telescopic leg 21 is provided with a first roller 221 inside the second-stage telescopic leg 22 for rolling support of the cylinder barrel 31t of the first piston cylinder 31. In this way, the first piston cylinder 31 can realize stable rolling support of the cylinder barrel 31t through the first roller 221 during the telescopic process.

[0122] Referring to FIGS. 10 and 11, in some embodiments, the piston cylinder end 32r of the second piston cylinder 32 is fixedly connected to the root of the first-stage telescopic leg 21, and the cylinder barrel 32t of the second piston cylinder 32 is fixedly connected to the second-stage telescopic leg 22 and passes through the root of the third-stage telescopic leg 23, and the second-stage telescopic leg 22 is provided with a second roller 231 inside the third-stage telescopic leg 23 for rolling support of the cylinder barrel 32t of the second piston cylinder 32. In this way, the second piston cylinder 32 can realize stable rolling support of the cylinder barrel 32t through the second roller 231 during the telescopic process.

[0123] Referring to the rope transmission mechanism in the foregoing embodiments, in other embodiments, the mechanical traction transmission mechanism 40 can be a chain and sprocket transmission mechanism, the guide rotating member is a sprocket set in the chain and sprocket transmission mechanism, and the traction member is a chain set in the chain and sprocket transmission mechanism.

[0124] Specifically, referring to the rope-and-block transmission mechanism shown in FIGS. 10 and 11, the pulleys are replaced by sprockets, and the traction ropes are replaced by chains. That is, the sprocket set includes a first sprocket and a second sprocket, the first sprocket is arranged at the tail of the second telescopic leg 22, and the second sprocket is arranged at the root of the second telescopic leg 22. The chain set includes a first chain and a second chain, one end of the first chain is fixedly connected to the root of the third telescopic leg 23, and the other end is fixedly connected to the tail of the first telescopic leg 21 after passing around the first sprocket, and one end of the second chain is fixedly connected to the root of the third telescopic leg 23, and the other end is fixedly connected to the tail of the first telescopic leg 21 after passing around the second sprocket.

[0125] FIG. 12 is a schematic diagram of the hydraulic control principle of the first piston cylinder and the second piston cylinder in some embodiments of the telescopic leg structure according to the present disclosure. FIG. 13 is a schematic diagram of the configuration of the hydraulic control circuit shown in FIG. 12 on the telescopic leg structure.

[0126] Referring to FIGS. 12 and 13, in some embodiments, the telescopic drive mechanism further includes a hydraulic control system, which includes a hydraulic pump 71, a hydraulic oil tank 72, a first directional valve 74, a throttle valve 75, a check valve 76, a second directional valve 77, and a third directional valve 78. The hydraulic pump 71 is in communication with an oil inlet of the first directional valve 74 through an oil inlet oil line, the hydraulic oil tank 72 is in communication with an oil return of the first directional valve 74 through an oil return oil line, one working oil port of the first directional valve 74 is in communication with the rodless chamber of the first piston cylinder 31 and the second piston cylinder 32, and the other working oil port is in communication with the rod chamber of the first piston cylinder 31 and the second piston cylinder 32. The second directional valve 77 is arranged on the hydraulic oil line between the first directional valve 74 and the rodless chamber of the second piston cylinder 32, the third directional valve 78 is arranged on the hydraulic oil line between the first directional valve 74 and the rod chamber of the first piston cylinder 31, and the throttle valve 75 and the check valve 76 are connected in parallel and in series on the hydraulic oil line between the first directional valve 74 and the rod chamber of the first piston cylinder 31.

[0127] In FIGS. 12 and 13, the second directional valve 77 and the third directional valve 78 can each be an electromagnetic valve having a first working position and a second working position. In the first working position, the connected oil line is bidirectional, and in the second working position, the connected oil line is unidirectional.

[0128] When the first reversing valve 74 is switched to the left position shown in Fig. 12, the hydraulic pump 71 pumps pressure oil into the rodless chamber of the first piston cylinder 31 through the inside oil passage of the cylinder rod, and pushes the first piston cylinder 31 to extend. The oil in the rod chamber of the first piston cylinder 31 is pushed out and in turn pushes away the one-way conduction structure inside the second reversing valve 77 and the one-way valve 76, and then flows back to the hydraulic oil tank 72 through the first reversing valve 74. When the first piston cylinder 31 extends to the end, the third reversing valve 78 is switched to the bidirectional conduction position, and the pressure oil flowing to the rodless chamber of the first piston cylinder 31 flows smoothly into the rodless chamber of the second piston cylinder 32 through the third reversing valve 78, and then pushes the second piston cylinder 32 to extend. The second piston cylinder 32 flows back to the hydraulic oil tank 72 through the one-way valve 76 and the first reversing valve 74.

[0129] Here, the way to determine that the first piston cylinder 31 extends to the end can be observation by an operator, or collection by a position detection switch or displacement sensor, which will not be described here. In Fig. 13, the third reversing valve 78 can be arranged on the primary telescopic leg 21.

[0130] When the first reversing valve 74 is switched to the right position shown in Fig. 12, the hydraulic pump 71 pumps pressure oil into the rod chamber of the second piston cylinder 32 through the throttle valve 75 (such as a damping hole), and pushes the second piston cylinder 32 to retract. The oil in the rodless chamber of the second piston cylinder 32 is pushed out and pushes away the one-way conduction structure inside the third reversing valve 78, and then flows back to the hydraulic oil tank 72 through the first reversing valve 74. When the second piston cylinder 32 retracts to the end, the second reversing valve 77 is switched to the bidirectional conduction position, and the pressure oil flows smoothly into the rod chamber of the first piston cylinder 31 through the second reversing valve 77, and then pushes the first piston cylinder 31 to retract. The oil in the rodless chamber of the first piston cylinder 31 flows back to the hydraulic oil tank 72 through the first reversing valve 74.

[0131] Here, the way to determine that the second piston cylinder 32 retracts to the end can be observation by an operator, or collection by a position detection switch or displacement sensor, which will not be described here.

[0132] Compared with the hydraulic control system using sequence valves, the present embodiment cancels the sequence valves, and uses electromagnetic reversing valves with one-way conduction and bidirectional conduction positions, and uses the one-way conduction function to realize sequence extension and retraction. In this way, the number of valve groups in the system is reduced, and the problem of being unable to sequence extension and retraction in the whole life cycle is completely solved.

[0133] In FIGS. 12 and 13, the hydraulic control system can further include a relief valve 73, the inlet and outlet of which are connected to the oil inlet line and the oil return line, respectively, to achieve a relief protection function. In addition, referring to FIG. 13, in some embodiments, the hydraulic control system further includes a drag chain mechanism 79 for dragging the hydraulic pipes and electrical harnesses of the fixed outrigger 10 to the second piston cylinder 32.

[0134] The outrigger telescopic structure of the above embodiments can be used in various engineering machinery devices requiring the use of outriggers, such as cranes, concrete pump trucks, etc. In one aspect of the present disclosure, a crane is also provided, which includes the outrigger telescopic structure of any of the above embodiments.

[0135] So far, the 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. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein according to the above description.

[0136] Although some specific embodiments of the present disclosure have been described in detail through examples, those skilled in the art should understand that the above examples are only for illustration, not for limiting the scope of the present disclosure. Those skilled in the art should understand that the above embodiments can be modified or some technical features can be replaced equivalently 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 telescopic leg structure, comprising: a fixed leg (10); and a multi-stage telescopic leg (20) telescopically arranged in the fixed leg (10) and adjustable in total length in a telescopic direction by telescoping; wherein an overlap block cooperation structure is provided between adjacent stages of the multi-stage telescopic leg (20), the overlap block cooperation structure comprising a first overlap block group (50) on an outer web surface (2o) of an inner telescopic leg of the adjacent stages and a second overlap block group (60) on an inner web surface (2i) of an outer telescopic leg of the adjacent stages, the first overlap block group (50) and the second overlap block group (60) being cooperatively overlapped at any position between a maximum allowed extended position and a set extended position of the inner telescopic leg relative to the outer telescopic leg. The first overlap block group (50) comprises a rear overlap block (51) and a first continuous overlap block group (52) arranged in the telescopic direction, and the second overlap block group (60) comprises a front overlap block (61) and a second continuous overlap block group (62) arranged in the telescopic direction, the rear overlap block (51) being located at a position adjacent to a root of the inner telescopic leg on the outer web surface (2o) and cooperatively overlapped with the second continuous overlap block group (62) on the inner web surface (2i) of the outer telescopic leg, and the front overlap block (61) being located at a position adjacent to a tail of the outer telescopic leg on the inner web surface (2i) and cooperatively overlapped with the first continuous overlap block group (52) on the outer web surface (2o) of the inner telescopic leg.

2. The leg retraction structure according to claim 1, wherein, The front overlap block (61) is located above the first continuous overlap block group (52), and the rear overlap block (51) is located above the second continuous overlap block group (62).

3. The leg retraction structure of claim 2, wherein, The first continuous overlap block group (52) is located between the rear overlap block (51) and the tail of the inner telescopic leg and has a first overlap range that is continuous in the telescopic direction, the length of the first overlap range in the telescopic direction being greater than the length of the front overlap block (61) in the telescopic direction.

4. The leg retraction structure according to claim 2 or 3, wherein, The first continuous overlap block group (52) comprises:

5. The leg retraction structure of claim 4, wherein, a first overlap block (521) configured to cooperatively overlap with the front overlap block (61) when the inner telescopic leg is at the set extended position relative to the outer telescopic leg; a second overlap block (522) configured to cooperatively overlap with the front overlap block (61) when the inner telescopic leg is at the maximum allowed extended position relative to the outer telescopic leg; and ​ A first transition lap piece (523) is located between the first lap piece (521) and the second lap piece (522), and two ends of the first transition lap piece (523) in the telescopic direction are connected with the first lap piece (521) and the second lap piece (522) respectively, and the lap faces of the first lap piece (521), the first transition lap piece (523) and the second lap piece (522) are flush with each other for lap joint with the front lap piece (61).

6. The legging structure of claim 5, wherein, The set extended position is a position where the inner telescopic leg is extended N times of the maximum stroke relative to the outer telescopic leg, and N satisfies 0≤N≤3 / 4, and the allowable maximum extended position is a position where the inner telescopic leg is extended the maximum stroke relative to the outer telescopic leg.

7. The leg retraction structure according to claim 5 or 6, wherein, The first lap piece (521) and the second lap piece (522) have a closed figure in a vertical direction of a web outer surface (2o) of the inner telescopic leg, the first transition lap piece (523) includes a first support strip (523a) extending in the telescopic direction and at least one first reinforcing rib (523b) arranged between the first support strip (523a) and the web outer surface (2o) of the inner telescopic leg.

8. The legging structure of any of claims 4-7, wherein, The front lap piece (61) is provided with a transition chamfer at a lap starting position and / or a lap ending position of the first continuous lap piece group (52) in the telescopic direction.

9. The legging retraction structure according to any one of claims 2-8, wherein, The second continuous lap piece group (62) is located between the front lap piece (61) and the root of the outer telescopic leg, and has a second lap range which is continuous in the telescopic direction, and the length of the second lap range in the telescopic direction is greater than the length of the rear lap piece (51) in the telescopic direction.

10. The leg retraction structure of claim 9, wherein, The second continuous lap piece group (62) includes: A third lap piece (621) configured to lap joint with the rear lap piece (51) when the inner telescopic leg is in the allowable maximum extended position relative to the outer telescopic leg; and A second transition lap piece (622) located between the third lap piece (621) and the root of the outer telescopic leg and connected with the third lap piece (621), and the lap faces of the third lap piece (621) and the second transition lap piece (622) are flush with each other for lap joint with the rear lap piece (51).

11. The legging structure of claim 10, wherein, The allowable maximum extended position is a position where the inner telescopic leg is extended the maximum stroke relative to the outer telescopic leg.

12. The leg retraction structure according to claim 10 or 11, wherein, The third lap piece (621) has a closed figure in a vertical direction of a web inner surface (2i) of the outer telescopic leg, and the second transition lap piece (622) includes a second support strip (622a) extending in the telescopic direction and at least one second reinforcing rib (622b) arranged between the second support strip (622a) and the web outer surface (2o) of the inner telescopic leg.

13. The legging retraction structure according to any one of claims 9-12, wherein, The rear lap block (51) is provided with a transition chamfer at the lap starting position and / or the lap ending position of the second continuous lap block group (62) in the telescopic direction.

14. The telescoping leg structure of any of claims 1-13, wherein, Further comprising: a telescopic driving mechanism for driving the telescoping of the multi-stage telescopic leg (20) itself and the telescoping of the multi-stage telescopic leg (20) relative to the fixed leg (10); wherein the telescopic driving mechanism comprises at least one piston cylinder.

15. The legging retraction structure of claim 14, wherein, The multi-stage telescopic leg (20) comprises: a first-stage telescopic leg (21) telescopically arranged in the fixed leg (10); a second-stage telescopic leg (22) telescopically arranged in the first-stage telescopic leg (21); and a third-stage telescopic leg (23) telescopically arranged in the second-stage telescopic leg (22); wherein the telescopic driving mechanism comprises: a first piston cylinder (31) fixedly connected at one end to the fixed leg (10) and connected at the other end to the first-stage telescopic leg (21), configured to drive the telescoping of the first-stage telescopic leg (21) relative to the fixed leg (10); a second piston cylinder (32) fixedly connected at one end to the first-stage telescopic leg (21) and connected at the other end to the second-stage telescopic leg (22), configured to drive the telescoping of the second-stage telescopic leg (22) relative to the first-stage telescopic leg (21); and a mechanical traction transmission mechanism (40) arranged in the second-stage telescopic leg (22) and the third-stage telescopic leg (23), configured to drive the telescoping of the third-stage telescopic leg (23) relative to the second-stage telescopic leg (22) through mechanical traction under the driving of the second-stage telescopic leg (22).

16. The legging structure of claim 15, wherein, 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 is arranged on the second-stage telescopic leg (22), the traction member is wound around the guide rotating member and connected at both ends to the second-stage telescopic leg (22) and the third-stage telescopic leg (23) respectively.

17. The legging retraction structure of claim 16, wherein, The mechanical traction transmission mechanism (40) is a rope transmission mechanism, the guide rotating member is a pulley set in the rope transmission mechanism, and the traction member is a traction rope set in the rope transmission mechanism.

18. The legging retraction structure of claim 17, wherein, The pulley set comprises a first pulley (41) arranged at the tail of the second-stage telescopic leg (22) and a second pulley (42) arranged at the root of the second-stage telescopic leg (22), and the traction rope set comprises a first traction rope (43) and a second traction rope (44), one end of the first traction rope (43) is fixedly connected to the root of the third-stage telescopic leg (23), the other end is fixedly connected to the tail of the first-stage telescopic leg (21) after being wound around the first pulley (41), and one end of the second traction rope (44) is fixedly connected to the root of the third-stage telescopic leg (23), the other end is fixedly connected to the tail of the first-stage telescopic leg (21) after being wound around the second pulley (42).

19. The legging retraction structure of claim 16, wherein, The mechanical traction transmission mechanism (40) is a chain and sprocket transmission mechanism, the guide rotating part is a sprocket set in the chain and sprocket transmission mechanism, and the traction part is a chain set in the chain and sprocket transmission mechanism.

20. The legging retraction structure of claim 19, wherein, The sprocket set includes a first sprocket and a second sprocket, the first sprocket is arranged at the tail of the second telescopic leg (22), and the second sprocket is arranged at the root of the second telescopic leg (22); the chain set includes a first chain and a second chain, one end of the first chain is fixedly connected with the root of the third telescopic leg (23), and the other end of the first chain is fixedly connected with the tail of the first telescopic leg (21) after passing through the first sprocket; one end of the second chain is fixedly connected with the root of the third telescopic leg (23), and the other end of the second chain is fixedly connected with the tail of the first telescopic leg (21) after passing through the second sprocket.

21. The telescoping leg structure of any of claims 16-20, wherein, One end of the traction part is connected with the first telescopic leg (21) through an adjustable length screw rod (45), and / or the other end of the traction part is connected with the third telescopic leg (23) through an adjustable length screw rod (45).

22. The telescoping leg structure of any of claims 15-21, wherein, The mechanical traction transmission mechanism (40) is located at the lower side of the first piston cylinder (31) and the second piston cylinder (32).

23. The telescoping leg structure of any of claims 15-22, wherein, The first piston cylinder (31) and the second piston cylinder (32) are configured to be synchronously telescopic, independently telescopic or sequentially telescopic.

24. The telescoping leg structure of any of claims 15-23, wherein, The piston cylinder end (31r) of the first piston cylinder (31) is fixedly connected with the root of the fixed leg (10), the cylinder barrel (31t) of the first piston cylinder (31) is fixedly connected with the first telescopic leg (21) and passes through the root of the second telescopic leg (22), and the first roller (221) is arranged in the second telescopic leg (22) to rollingly support the cylinder barrel (31t) of the first piston cylinder (31).

25. The legging retraction structure of any of claims 15-24, wherein, The piston cylinder end (32r) of the second piston cylinder (32) is fixedly connected with the root of the first telescopic leg (21), the cylinder barrel (32t) of the second piston cylinder (32) is fixedly connected with the second telescopic leg (22) and passes through the root of the third telescopic leg (23), and the second roller (231) is arranged in the third telescopic leg (23) to rollingly support the cylinder barrel (32t) of the second piston cylinder (32).

26. The telescoping leg structure of any of claims 15-25, wherein, The telescopic drive mechanism further comprises a hydraulic control system, which comprises a hydraulic pump (71), a hydraulic oil tank (72), a first reversing valve (74), a throttle valve (75), a one-way valve (76), a second reversing valve (77) and a third reversing valve (78), the hydraulic pump (71) is communicated with an oil inlet of the first reversing valve (74) through an oil inlet oil path, the hydraulic oil tank (72) is communicated with an oil return port of the first reversing valve (74) through an oil return oil path, one working oil port of the first reversing valve (74) is communicated with a rodless cavity of the first piston cylinder (31) and the second piston cylinder (32), and the other working oil port is communicated with a rod cavity of the first piston cylinder (31) and the second piston cylinder (32), the second reversing valve (77) is arranged on a hydraulic oil path between the first reversing valve (74) and the rodless cavity of the second piston cylinder (32), the third reversing valve (78) is arranged on a hydraulic oil path between the first reversing valve (74) and the rod cavity of the first piston cylinder (31), the throttle valve (75) and the one-way valve (76) are connected in parallel and connected in series on the hydraulic oil path between the first reversing valve (74) and the rod cavity of the first piston cylinder (31).

27. The legging retraction structure of claim 26, wherein, The second reversing valve (77) and the third reversing valve (78) are both solenoid valves, the solenoid valves have a first working position and a second working position, and in the first working position, the connected oil path is bidirectional, and in the second working position, the connected oil path is unidirectional.

28. The leg retraction structure of claim 26 or 27, wherein, The hydraulic control system further comprises: A drag chain mechanism (79) is used to drag the hydraulic pipeline and the electrical wire harness of the second piston cylinder (32) to the fixed leg (10).

29. The telescopic leg structure according to any one of claims 1-28, further comprising: A vertical leg (80) is arranged at the tail of the multi-stage telescopic leg (20) and is configured to realize the support function in the vertical direction.

30. A crane, comprising: The telescopic leg structure according to any one of claims 1-29.

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