Tensioning mechanism for truss boom, tensioning method and hoisting apparatus

Abstract

The present application relates to the field of engineering machinery, and provides a tensioning mechanism for a truss boom, a tensioning method and a hoisting apparatus. The tensioning mechanism comprises supporting rod assemblies, second connecting assemblies, first connecting assemblies, third connecting assemblies and driving assemblies. The two supporting rod assemblies are symmetrically arranged at the top of a truss boom. Each second connecting assembly is located between a free end of the corresponding supporting rod assembly and one end of the truss boom, and is used for limiting the position of the corresponding supporting rod assembly. Each first connecting assembly is located between the free end of the corresponding supporting rod assembly and the other end of the truss boom, and the supporting rod assemblies are connected to the truss boom by means of the connecting assemblies. The driving assemblies are used for changing the position of the supporting rod assemblies. According to the tensioning mechanism provided by the present application, the degree of tension of the first connecting assemblies is adjusted by means of a displacement mechanism, so that pre-tightening forces are generated on two sides of the truss boom, thereby improving the lateral stability of the truss boom, and then improving the bearing capacity of the truss boom.

Description

Tensioning mechanism, tensioning method and lifting equipment for truss boom Technical Field

[0001] The present application relates to the field of engineering machinery, and in particular to a tensioning mechanism, a tensioning method and a lifting device for a truss-type boom. Background Art

[0002] A crawler crane is a truss-type boom structure crane with a lifting arm, luffing device and slewing device installed on a walking crawler chassis.

[0003] Typically, a lifting device with a truss boom structure has a lower part and an upper part, and the lower part is rotatably connected to the upper part via a slewing device. One end of the truss boom is pivotally connected to one end of the upper part, and the other end of the truss boom is connected to the other end of the upper part via a luffing device. The walking mechanism of the lower part can be crawler-type or wheel-type. During hoisting, in addition to bearing the weight of the load, the boom is also affected by the external environment, such as the flatness of the ground, wind load, etc. The higher the height to be hoisted (such as wind power installation), the longer the boom is, and the greater the impact caused by external factors. Because the truss boom is provided with a luffing mechanism, the luffing mechanism is connected to the boom head by a pull plate or a pull rope in the luffing plane. When working, it is equivalent to fixing the degree of freedom of the boom head in the luffing plane, thereby improving the stability of the boom luffing plane, and then improving the carrying capacity of the luffing plane. Therefore, the load-bearing capacity of the luffing plane is much greater than that of the slewing plane (the luffing plane and the slewing plane are perpendicular to each other, the luffing plane is the plane on which the boom swings, and the direction perpendicular to the boom's luffing plane is understood to be lateral). However, due to the boom's weak lateral load-bearing capacity, the overall load-bearing capacity of the truss boom is weak, which in turn weakens the lifting capacity of the entire machine.

[0004] Summary of the Invention

[0005] The present application provides a tensioning mechanism for a truss-type boom, so as to solve the problem of insufficient load-bearing capacity of existing truss-type booms.

[0006] In a first aspect, the present application provides a tensioning mechanism for a truss boom, comprising a strut assembly, a second connecting assembly, a first connecting assembly, a third connecting assembly, and a drive assembly. Two strut assemblies are symmetrically arranged at the top of the truss boom. The second connecting assembly is located between the free end of the strut assembly and one end of the truss boom and is used to limit the position of the strut assembly. The first connecting assembly is located between the free end of the strut assembly and the other end of the truss boom and is used to connect to the displacement mechanism of the strut assembly. The strut assembly is connected to the truss boom via the third connecting assembly. The drive assembly is used to change the position of the strut assembly.

[0007] In a possible implementation, the tensioning mechanism further includes a mounting frame connected to the drive assembly and connecting the support rod assembly and the truss boom.

[0008] In one possible implementation, the drive assembly includes a first joint, a second joint, a first drive member, and a second drive member. The first joint is connected to the mounting bracket. The first end of the second joint is hingedly connected to the first joint. The first drive member is hingedly connected to the first joint and the second end of the second joint, and the first drive member is used to drive the second joint to rotate. The first end of the brace assembly is hingedly connected to the second joint, and the second drive assembly is hingedly connected to the brace assembly and the second joint, and the second drive member is used to drive the brace assembly to rotate.

[0009] In a possible implementation, the first joints corresponding to the two strut assemblies are an integrated structure.

[0010] In one possible implementation, the truss boom includes a lower arm at its distal end, and the strut assembly includes a strut having a first end provided with a locating groove located on a side of the strut facing away from the lower arm. When the strut is in an operating state, the second end of the second joint abuts against the sidewalls and bottom wall of the locating groove.

[0011] In one possible implementation, limit blocks are provided on both sides of the truss boom, the strut assembly includes a strut, and the limit blocks are connected to the truss boom through a connecting rod. When the strut is in a working state, the strut is located above the limit block, and the bottom surface of the first end of the strut abuts against the limit block.

[0012] In one possible implementation, the drive assembly further includes an intermediate support rod and a third drive member. The two intermediate support rods are symmetrically disposed at the front of the lattice boom and connected to corresponding first connecting assemblies. The second drive member is hingedly connected to the lattice boom and to one end of the intermediate support rod remote from the first connecting assembly.

[0013] In one possible implementation, the truss boom includes a lower arm at its end, the first connecting assembly includes a first pull plate, two universal joints are provided at one end of the truss boom away from the lower arm, and the second end of the first pull plate is hinged to the corresponding universal joint.

[0014] In a possible implementation, the mounting frame is detachably connected to the truss boom, or is integrally formed with the truss boom.

[0015] In a second aspect, the present application further provides a tensioning method, which is based on any of the above tensioning mechanisms and includes:

[0016] The driving assembly drives the strut assembly to move to the open position, so that the second connecting assembly is in a tensioned state;

[0017] The displacement mechanism drives the first connecting assembly to be in a tensioned state.

[0018] In one possible implementation, the driving assembly driving the strut assembly to move to the open position includes:

[0019] The second driving member drives the brace assembly to rotate in a plane parallel to the truss boom so that the brace assembly is perpendicular to the truss boom;

[0020] The first driving member drives the second joint to rotate so that the support rod assembly moves to the open position.

[0021] In a possible implementation, the displacement mechanism includes a hoisting mechanism and a tightening mechanism, and the displacement mechanism drives the first connecting assembly to be in a tensioned state including:

[0022] The winch mechanism winds part of the wire rope around the winch mechanism;

[0023] The tightening mechanism drives the steel wire rope to move so that the first connecting assembly is in a tensioned state.

[0024] On the third aspect, the present application also provides a lifting equipment, including a lifting equipment body, an arm and the above-mentioned tensioning mechanism, and the arm is connected to the lifting equipment body and the tensioning mechanism.

[0025] The tensioning mechanism for a truss boom provided in the present application limits the position of the strut assembly through a second connecting assembly, changes the position of the strut assembly through a driving assembly, and adjusts the tensioning degree of the first connecting assembly through a displacement mechanism, so that a pre-tightening force is generated on both sides of the truss boom, thereby improving the lateral stability of the truss boom and further improving the load-bearing capacity of the truss boom. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] To more clearly illustrate the technical solutions of this application or the prior art, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are some embodiments of this application. Those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0027] FIG1 is a schematic structural diagram of a tensioning mechanism for a truss-type boom provided in one embodiment of the present application.

[0028] FIG2 is a schematic diagram of a partially enlarged structure of point A in FIG1 .

[0029] FIG3 is a schematic diagram of the three-dimensional structure of a support rod component provided in one embodiment of the present application.

[0030] FIG4 is a schematic diagram of the three-dimensional structure of the second joint provided in one embodiment of the present application.

[0031] FIG5 is a first schematic diagram of the state of a strut component of a tensioning mechanism for a truss-type boom provided in accordance with an embodiment of the present application.

[0032] FIG6 is a second schematic diagram of the state of a strut component of a tensioning mechanism for a truss-type boom provided in one embodiment of the present application.

[0033] FIG7 is a third schematic diagram of the state of a strut component of a tensioning mechanism for a truss-type boom provided in one embodiment of the present application.

[0034] FIG8 is a fourth schematic diagram of the state of a strut component of a tensioning mechanism for a truss-type boom provided in one embodiment of the present application.

[0035] FIG9 is a schematic structural diagram of an upper transition section provided in one embodiment of the present application.

[0036] FIG10 is a working state diagram of a tensioning mechanism for a truss-type boom provided in one embodiment of the present application.

[0037] FIG11 is a schematic diagram of the front structural view of a support rod component provided in one embodiment of the present application.

[0038] FIG12 is a schematic diagram of a partial structure of a tensioning mechanism of a truss-type boom provided in another embodiment of the present application.

[0039] FIG13 is a flow chart of a tensioning method provided in one embodiment of the present application.

[0040] FIG14 is a flow chart of a tensioning method provided in another embodiment of the present application.

[0041] FIG15 is a flow chart of a tensioning method provided in yet another embodiment of the present application.

[0042] Reference numerals:

[0043] 10. Boom; 11. Lower boom; 12. Universal joint;

[0044] 20. Mounting frame; 21. Upper transition section;

[0045] 31. First connecting assembly; 32. Support rod assembly; 33. Drive assembly;

[0046] 40. A second connection component;

[0047] 310, movable pulley; 311, steel wire rope; 312, first pull plate;

[0048] 320, support rod; 321, hoisting mechanism; 322, tightening mechanism; 323, first fixed pulley; 324, second fixed pulley;

[0049] 330, first joint; 331, second joint; 332, first driving member; 333, second driving member / third connecting assembly; 334, positioning groove; 336, intermediate support rod; 337, third driving member;

[0050] 410. Second pull plate; 411. Connecting piece. DETAILED DESCRIPTION

[0051] To make the objectives, technical solutions, and advantages of this application more clear, the technical solutions of this application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.

[0052] Known telescopic boom lifting equipment generally has a super-lifting mechanism detachably installed at one end of the telescopic boom close to the upper part of the vehicle, which enhances its lateral load-bearing capacity through the super-lifting mechanism, thereby improving the load-bearing capacity of the boom. The main differences between telescopic boom lifting equipment and truss-type lifting equipment include: the cross-section of the telescopic boom is usually a combination of an open rectangle and an arc, while the cross-section of the truss-type boom is usually a rectangle. Before lifting, the telescopic boom will be pre-varied to a predetermined position by the variable-length cylinder, and then the multi-section boom will be extended or retracted to the specified length before the lifting action is performed. Before the truss-type boom is lifted, a fixed-length boom will be pre-assembled on the ground, and then the boom will be pulled to the predetermined position by the variable-length device to perform the lifting. That is, there is a difference in the working principle of the variable-length mechanism of the above-mentioned two types of lifting equipment. If the super-lifting device in the telescopic boom lifting equipment (such as the wheeled telescopic boom) is installed in the truss-type boom, the following problems will arise. Because the telescopic boom first changes the boom angle before lifting, and then the boom is extended to a predetermined length, the multiple boom sections need to be extended or shortened to the predetermined length. Therefore, before lifting, the wire rope in the super-lifting device needs to be extended or shortened to the corresponding rope length according to the length of the telescopic boom. However, the truss boom is of a predetermined length, that is, the boom of a predetermined length is assembled first, and then the boom is changed to a predetermined position. This is one of the reasons why the super-lifting device used in the telescopic boom is not suitable for direct transfer to the truss boom. Specifically, to install the super-lifting device in the telescopic boom on the side of the truss boom, one end of the wire rope needs to be pulled out a long distance (tens or hundreds of meters). The wire rope will bend downward due to its own weight, making the actual disassembly and assembly of the super-lifting process extremely difficult. Auxiliary lifting equipment needs to be added, which greatly increases the operator's operating difficulty and installation cost.

[0053] The specific structure of the tensioning mechanism for the truss boom of the present application will be described below with reference to FIG. 1 to FIG. 11 .

[0054] As shown in Figure 1, the tensioning mechanism for the lattice boom includes a brace assembly 32, a second connecting assembly 40, a first connecting assembly 31, a third connecting assembly, and a drive assembly 33. Two brace assemblies 32 are symmetrically arranged on top of the lattice boom 10. The second connecting assembly 40 is located between the free ends of the brace assemblies 32 and one end of the lattice boom 10 and is used to limit the position of the brace assemblies 32. The second connecting assembly 40 is composed of a fixed-length rope or a pull plate.

[0055] The first connecting assembly 31 is located between the free end of the strut assembly 32 and the other end of the truss boom 10. The first connecting assembly 31 is used to connect to the displacement mechanism of the strut assembly 32. The strut assembly 32 is connected to the truss boom 10 via a third connecting assembly, and the drive assembly 33 is used to change the position of the strut assembly 32. The first connecting assembly 31 is composed of several pull plates of different or equal lengths connected in sequence by pins. To achieve the swing of the boom on the variable amplitude plane, two pull plates and corresponding pull plate holders are usually provided at the top of the boom. The pull plates are set in the holder at the top of the boom. The pull plates here can use the pull plates used in conjunction with the boom (factory-matched), which can reduce the cost of using the tensioning device. It is also possible to remanufacture a pull plate structure suitable for the tensioning device and place the remanufactured pull plate in the holder at the top of the original boom. To further enhance the use value of the remanufactured pull plates, the remanufactured pull plates are used in conjunction with the boom's own pull plates. However, because the pull plate is clamped in the holder at the top of the arm, a tensioning device is installed at the top of the arm to facilitate pulling the pull plate. Furthermore, to reduce the lateral force exerted by the pull plate on the tensioning device, the axis of the tensioning device and the axis of the pull plate are arranged in the same plane (not shown in the figure). Specifically, when the axis of the pull plate and the axis of the tensioning device are at an angle, the pull plate will exert a lateral force on the tensioning device due to its own weight. To reduce or eliminate the impact of lateral force on the tensioning device, it is necessary to increase the driving force output by the drive assembly 33.

[0056] The tensioning mechanism for a truss boom provided in this application uses a second connecting assembly 40 to limit the position of a strut assembly 32, a drive assembly 33 to change the position of the strut assembly 32, and a displacement mechanism to adjust the tension of the first connecting assembly 31, thereby generating a preload on both sides of the truss boom 10. Wind loads acting on the sides of a truss boom can cause lateral deformation of the boom, which in turn reduces its load-bearing capacity. The specific principles behind this mechanism can be found in patent CN101549835B. This preload can reduce the lateral deformation of the truss boom 10, thereby improving its lateral stability and, consequently, its load-bearing capacity.

[0057] In one embodiment of the present application, the truss boom 10 is formed by connecting multiple truss boom sections through pins.

[0058] In one embodiment of the present application, the tensioning mechanism for the truss boom further includes a mounting bracket 20, which is connected to the drive assembly 33. The mounting bracket 20 is detachably connected to the truss boom 10 via a pin. Of course, the mounting bracket 20 can also be integrally formed with the truss boom 10 to reduce the number of components, simplify the structure, and lower production costs.

[0059] In one embodiment of the present application, the mounting frame 20 is welded from multiple tubes, and the cross-section of the tubes is circular, but may also be rectangular, regular polygonal, or other shapes. The mounting frame 20 is a rectangular parallelepiped and is used to connect the two brace assemblies 32 to the truss boom 10. During use, only the mounting frame 20 needs to be connected to the truss boom 10, which simplifies the installation process and improves installation efficiency. The cross-sectional dimensions of the mounting frame 20 at both ends are substantially the same as the corresponding cross-sectional dimensions of the truss boom 10. The mounting frame 20 can be installed as part of the truss boom 10 at the rear end (i.e., 1 / 8 to 1 / 5 of the boom length) or near the middle of the boom (i.e., 1 / 2 of the boom length). The mounting frame 20 and the truss boom 10 are connected by a pin. Of course, the mounting frame 20 can also be integrated with the adjacent boom section, that is, the brace assembly 32 is directly mounted on the truss boom 10.

[0060] It should be noted here that, in Figure 1, the directions indicated by the front and rear arrows are the length directions of the truss boom 10, the directions indicated by the left and right arrows are the width directions of the truss boom 10, and the direction perpendicular to the planes where the two arrows are located is the up and down direction.

[0061] It should be noted here that the size of the mounting frame 20 refers to the length and width of the cross section of the mounting frame 20 , and the size of the truss boom 10 refers to the length and width of the cross section of the truss boom 10 .

[0062] Furthermore, in order to facilitate the connection between the mounting frame 20 and the truss boom 10, connectors are provided at both ends of the mounting frame 20, and the connectors are welded to the truss boom 10. The connectors are provided with connection holes and are connected to the truss boom 10 via fixed pins.

[0063] In one embodiment of the present application, as shown in FIG1 , two brace assemblies 32 are spaced apart at the top of the mounting frame 20 along the width direction of the truss boom 10. The brace assemblies 32 are adapted to switch between a working state and a mounted state. In the working state, the two brace assemblies 32 are located on either side of the truss boom 10, and both brace assemblies 32 form a predetermined angle with the axis of the truss boom 10. The working state is the deployed state of the brace assemblies 32. In the deployed state, the two brace assemblies 32 are located on either side of the truss boom 10, tightening the first connecting assembly 31 to generate a preload force on both sides of the truss boom 10. By providing the preload force, the overall ability of the truss boom 10 to resist lateral wind loads is improved, thereby enhancing the lateral stability of the boom and increasing the load-bearing capacity of the truss boom 10.

[0064] The predetermined angle in this embodiment is 90°, that is, the brace assembly 32 is perpendicular to the truss boom 10. Of course, the positional relationship between the brace assembly 32 and the truss boom 10 is not limited to this, and the predetermined angle can also be an acute angle or an obtuse angle.

[0065] Referring to Figure 2 , the brace assembly 32 includes brace rods 320. As shown in Figures 5 and 6 , in the installed state, the two brace assemblies 32 are located at the top of the lattice boom 10 and are parallel to the axis of the lattice boom 10. That is, the brace rods 320 are substantially parallel to the lattice boom 10. In this position, the first tension plate 312 of the lattice boom 10 is aligned with the outer tension plates of the lattice boom 10. This prevents the lattice boom 10 from being subjected to lateral forces from its own weight due to misalignment between the axis of the first tension plate 312 and the brace rods 320.

[0066] In one embodiment of the present application, as shown in Figures 3 and 4, the drive assembly 33 includes a first joint 330, a second joint 331, a first drive member 332, and a second drive member 333. The first joint 330 is connected to the mounting frame 20. For example, the first joint 330 is detachably connected to the mounting frame 20 to facilitate installation and removal of the strut assembly 32. Specifically, the first joint 330 is provided with at least two pin holes, and the mounting frame 20 is provided with a corresponding number of pin seats corresponding to the installation positions of the first joint 330. Pins are provided in the pin holes, and the first joint 330 is connected to the truss boom 10 via the pins.

[0067] The first joint 330 is a U-shaped bracket, which is clamped on one side of the truss boom 10. The first joint 330 is clamped on one side of the truss boom 10 and fixed with at least one pin, which effectively improves the connection strength between the first joint 330 and the truss boom 10.

[0068] Furthermore, because the truss boom 10 is welded from a circular tube, the truss boom 10 has relatively few fixing surfaces for securing the first joint 330. To increase the number of pin seats for securing the first joint 330, pin seats are provided on both sides of the truss boom 10. The pin seats are rectangular steel plates, with their fixing plates welded to the circular tube that constitutes the truss boom 10. The fixing plates are designed with through-holes, the same number of which matches the number of pin holes on the first joint 330. The positions of the through-holes correspond one-to-one with the positions of the pin holes on the first joint 330, and the pins are inserted into the pin holes and the through-holes.

[0069] Preferably, the thickness of the pin seat is the same as the width of the slot of the first joint 330. In this way, when the first joint 330 is stuck in the pin seat, the first joint 330 can limit the pin seat in the width direction of the truss arm 10, further improving the stability of the first joint 330.

[0070] As shown in Figures 3 and 4, the first end of the second joint 331 is pivotally connected to the first joint 330. Specifically, a connector with a pin hole is provided at the top of the first joint 330, and a connector with a pin hole is provided at the first end of the second joint 331. The connector at the top of the first joint 330 is connected to the connector at the first end of the second joint 331 via a pin. Preferably, at least two connectors are provided at intervals at the first end of the second joint 331, and at least two connectors are provided at intervals at the top of the first joint 330. The connectors at the top of the first joint 330 and the connectors at the first end of the second joint 331 are arranged alternately and connected by the same pin.

[0071] The first driving member 332 is hingedly connected to the first joint 330 and the second end of the second joint 331. Specifically, the first driving member 332 includes a first oil cylinder. The outer side of the first joint 330 (i.e., the side of the two first joints 330 facing away from each other) is provided with a connector with a pin hole. The second end of the second joint 331 is provided with a connector with a pin hole. The outer side of the first joint 330 is hingedly connected to the cylinder body of the first oil cylinder via a pin, and the second end of the second joint 331 is hingedly connected to the telescopic rod of the first oil cylinder via a pin.

[0072] The first driving member 332 is used to drive the second joint 331 to rotate, thereby realizing the rotation of the strut assembly 32 relative to the first joint 330. The first driving member 332 includes a first oil cylinder. When the first oil cylinder is extended, the two second joints 331 approach each other. When the length of the first oil cylinder reaches its maximum value, the second joints 331 are in a vertical state and perpendicular to the truss boom 10. At this time, the strut assembly 32 is in an installed state. When the first oil cylinder is shortened, the two second joints 331 move away from each other. When the length of the first oil cylinder reaches its minimum value, the second joints 331 are in a horizontal state and perpendicular to the truss boom 10. At this time, the strut assembly 32 is in a working state.

[0073] The first end of the strut assembly 32 is hinged to the second joint 331, that is, the first end of the strut 320 is hinged to the second joint 331. Specifically, the end of the first end of the strut 320 is provided with a connector with a pin hole, and one side of the second joint 331 (that is, the side of the strut 320 facing the lower arm 11) is provided with a connector with a pin hole. The connector at the first end of the strut 320 is hinged to the connector on the side of the second joint 331 via a pin.

[0074] The second driving member 333 is hinged to the strut assembly 32 and the second joint 331, and is used to drive the strut assembly 32 to rotate. Specifically, the second driving member 333 includes a second oil cylinder, a connector with a pin hole is provided on one side of the first end of the strut 320 (i.e., the side of the strut 320 facing the lower arm 11), a connector with a pin hole is provided on one side of the second joint 331 (i.e., the side of the second joint 331 facing the lower arm 11), the telescopic rod of the second oil cylinder is hinged to the connector on one side of the second joint 331, and the cylinder body of the second oil cylinder is hinged to the connector on one side of the strut 320.

[0075] When the second cylinder's telescopic rod is shortened, the second end of the strut 320 approaches the lattice boom 10. When the second cylinder's telescopic rod reaches its minimum length, the strut 320 becomes substantially parallel to the lattice boom 10, facilitating assembly and transportation. When the second cylinder's telescopic rod is extended, the second end of the strut 320 moves away from the lattice boom 10. When the second cylinder's telescopic rod reaches its maximum length, the strut 320 becomes perpendicular to the lattice boom 10.

[0076] When the strut assembly 32 switches from the installation state to the working state, the second oil cylinder is first extended, and the strut 320 changes to a perpendicular position with respect to the truss boom 10 within the rotation plane of the truss boom 10. The first oil cylinder is then controlled to shorten, causing the second joint 331 to change its angle within the amplitude variation plane of the truss boom 10. Compared to the prior art, the tensioning mechanism for the truss boom of the present application is provided with two joints, which respectively control the angle change of the strut 320 within different planes of the truss boom 10, allowing the strut assembly 32 to move in multiple directions, thereby improving the flexibility of the strut assembly 32 and enhancing the product's competitiveness.

[0077] In a preferred embodiment of the present application, the first joints 330 corresponding to the two strut assemblies 32 are integrally formed, i.e., the two drive assemblies 33 share one first joint 330. This structural design reduces the number of components, simplifies the structure, reduces production costs, and improves assembly efficiency.

[0078] In a preferred embodiment of the present application, when the strut 320 is in operation, since the weight of the strut 320 is primarily borne by the hinge point between the first end of the second joint 331 and the first joint 330, as well as the first oil cylinder, in order to reduce the force acting on the first oil cylinder in operation, limit blocks (not shown) are provided on both sides of the truss boom 10. The limit blocks are connected to the truss boom 10 via connecting rods so that the limit blocks maintain a certain distance from the truss boom 10, thereby avoiding interference between the limit blocks and the first oil cylinder. When the strut 320 is in operation, the strut 320 is located above the limit blocks, and the bottom surface of the first end of the strut 320 abuts against the limit blocks. Part of the weight of the strut 320 is borne by the limit blocks, thereby reducing the pressure on the first oil cylinder and extending the service life of the first oil cylinder.

[0079] In a preferred embodiment of the present application, as shown in FIG3 , a positioning groove 334 is provided at the first end of the strut assembly 32, that is, a positioning groove 334 is provided at the first end of the strut 320, and the positioning groove 334 is located on the side of the strut 320 facing away from the lower arm 11. In the working state, the second end of the second joint 331 abuts against the bottom wall of the positioning groove 334. Specifically, the positioning groove 334 is a rectangular groove, and the positioning groove 334 is provided along the length direction of the strut 320. An opening is provided on one side of the positioning groove 334 so that the first end of the second joint 331 can enter the positioning groove 334. The other side of the positioning groove 334 has a side wall, and when the strut 320 is in the working state, the second end of the second joint 331 abuts against the side wall of the positioning groove 334.

[0080] When the strut 320 is in operation, the second end of the second joint 331 abuts against the bottom wall of the positioning groove 334. Although the first connecting assembly 31 applies a forward pulling force to the second strut 320, the second end of the second joint 331 acts as a limiter on the strut 320, preventing the strut 320 from rotating forward. At this time, the second oil cylinder only needs to apply a very small force to the strut 320 to ensure that the strut 320 remains balanced. This design can extend the service life of the second oil cylinder. At the same time, because the second end of the second joint 331 abuts against the side wall of the positioning groove 334, the side wall of the positioning groove 334 can bear part of the weight of the strut 320 in the vertical direction, reducing the force acting on the hinge point between the first end of the strut assembly 32 and the second joint 331.

[0081] In a preferred embodiment of the present application, as shown in Figures 1 and 2, the strut assembly 32 further includes a displacement mechanism, which includes a hoisting mechanism 321 and a tightening mechanism 322. The two ends of the strut 320 are welded from metal plates, and the middle portion of the strut 320 is welded from a circular tube. The middle portion of the strut 320 is hollowed out to provide installation space for the hoisting mechanism 321 and the tightening mechanism 322. The first end of the strut 320 is hinged to the drive assembly 33, that is, the first end of the strut 320 is hinged to one side of the second joint 331. The hoisting mechanism 321 is disposed inside the strut 320 and connected to the first connecting assembly 31. The hoisting mechanism 321 is used to wind and release the wire rope 311. To facilitate the entry and exit of the wire rope 311, an opening is provided on the side of the strut 320 facing the lower arm 11, through which the wire rope 311 enters and exits the strut 320. The hoisting mechanism 321 includes a motor and a roller. The roller rotates with the inner wall of the support rod 320. The motor is connected to the roller and is used to drive the roller to rotate to control the winding and release of the wire rope 311.

[0082] The tightening mechanism 322 is disposed within the support rod 320 and connected to the first connecting assembly 31. The tightening mechanism 322 is used to adjust the tension of the first connecting assembly 31. Specifically, the tightening mechanism 322 includes a cylinder, the cylinder body of which is connected to the inner wall of the support rod 320, and the cylinder's telescopic rod is connected to the second end of the wire rope 311. The cylinder controls the tension of the wire rope 311 by extending and contracting. Of course, the specific type of tightening mechanism 322 is not limited to this; it can also be an electric push rod or other linear drive mechanism.

[0083] In a preferred embodiment of the present application, as shown in FIG2 , the first connecting assembly 31 includes a movable pulley 310, a wire rope 311, and a first pull plate 312. The wire rope 311 is wound around the movable pulley 310. The first end of the wire rope 311 is connected to the hoisting mechanism 321, and the second end of the wire rope 311 is connected to the tightening mechanism 322. That is, the second end of the wire rope 311 is connected to the telescopic rod of the oil cylinder. The first end of the first pull plate 312 is hinged to the movable pulley 310. Specifically, the movable pulley 310 is provided with a connector that is rotatably connected to the movable pulley 310, and the connector is connected to the first end of the first pull plate 312. The second end of the first pull plate 312 is connected to the end of the truss boom 10 away from the lower boom 11. When the truss boom 10 is subjected to wind load, the truss boom 10 will bend. However, due to the presence of the tensioning mechanism and the pre-tightening force, the bending deformation of the truss boom 10 can be greatly limited, thereby improving the lateral bearing capacity of the truss boom 10.

[0084] In a preferred embodiment of the present application, referring to Figure 12 , the tensioning mechanism for the lattice boom further includes intermediate support rods 336 and a third drive member 337. Two intermediate support rods 336 are symmetrically arranged at the front of the lattice boom 10, spaced a certain distance from the brace assembly 32 along the axis of the lattice boom 10, and connected to corresponding first connecting assemblies 31. Specifically, one end of each intermediate support rod 336 is hinged to the top of the lattice boom 10, allowing the two intermediate support rods 336 to rotate within the luffing plane. The other ends of the two intermediate support rods 336 are connected to the two first connecting assemblies 31 in a one-to-one manner.

[0085] The third drive member 337 is hingedly connected to the lattice boom 10 and one end of the intermediate support rod 336 away from the first connecting assembly 31. Specifically, the third drive member 337 is located on the side where the two intermediate support rods 336 are close to each other. The third drive member 337 includes a third oil cylinder. The cylinder bodies of the two third oil cylinders are hingedly connected to the lattice boom 10. The telescopic rods of the two third oil cylinders are hingedly connected to one end of the corresponding intermediate support rod 336. By controlling the extension and retraction of the two third oil cylinders, the angle between the two intermediate support rods 336 can be controlled. In a preferred embodiment of the present application, the tensioning mechanism for the lattice boom also includes a mounting base (not shown in the figure). The mounting base is connected to the top of the lattice boom 10. One end of the two intermediate support rods 336 is hingedly connected to the mounting base. The cylinder bodies of the two third oil cylinders are hingedly connected to the mounting base. The telescopic rods of the two third oil cylinders are hingedly connected to one end of the corresponding intermediate support rod 336.

[0086] In a preferred embodiment of the present application, as shown in Figures 4, 7, and 8, a hook is provided on the second joint 331 to facilitate the fixation of the movable pulley 310. The movable pulley 310 is hung on the hook to fix the movable pulley 310. When in use, the movable pulley 310 is removed from the hook and moved forward to connect with the first pull plate 312.

[0087] Referring to Figure 9, in one embodiment of the present application, two universal joints 12 are provided at the end of the truss boom 10 away from the lower boom 11, and the second ends of the two first tension plates 312 are articulated to the two universal joints 12 in a one-to-one correspondence. By using the universal joints 12 to connect the second ends of the first tension plates 312 to the end of the truss boom 10 away from the lower boom 11, the first tension plates 312 can be deployed synchronously with the struts 320 as the angle between the struts 320 and the truss boom 10 changes.

[0088] In a preferred embodiment of the present application, as shown in Figures 9 and 10, an upper transition section 21 is provided at one end of the truss boom 10 away from the lower boom 11. The upper transition section 21 is welded from multiple tubes. The cross-section of the tubes is circular, but can also be rectangular, regular polygonal, or other shapes. The upper transition section 21 is a rectangular parallelepiped. The dimensions of the upper transition section 21 are the same as those of the truss boom 10. The upper transition section 21 can be installed at the front end of the truss boom 10 as part of the truss boom 10. Two universal joints 12 are rotatably provided on the upper transition section 21, and the two universal joints 12 are spaced apart along the width direction of the upper transition section 21.

[0089] In a preferred embodiment of the present application, referring back to FIG2 , a first fixed pulley 323 and a second fixed pulley 324 are provided at the second end of the support rod 320. The first fixed pulley 323 is used to guide the first end of the wire rope 311 and is rotatably connected to the second end of the support rod 320 via a rotating shaft. The first end of the wire rope 311 passes around the first fixed pulley 323 and is then wound around the winch structure. The second end of the wire rope 311 passes around the second fixed pulley 324 and is connected to the take-up mechanism 322.

[0090] During the deployment of the strut 320, the hoisting mechanism 321 rotates to release the wire rope 311, causing the first pull plate 312 to be in a relaxed state. After the strut 320 reaches the operating state, the hoisting mechanism 321 rotates to tighten the wire rope 311, causing the first pull plate 312 to be in a taut state. The hoisting mechanism 321 then stops operating and controls the hydraulic cylinder to extend and retract, tightening the wire rope 311 through the hydraulic cylinder, so that the tension of the first pull plate 312 reaches the desired level.

[0091] As shown in Figures 1, 2, and 7, the strut assembly 32 also includes two second connecting assemblies 40, one corresponding to each of the two struts 320. The second connecting assembly 40 includes a second plate 410 and a connecting member 411. The connecting member 411 extends along the width of the lower boom 11 and is hinged to the lower boom 11 via a pin. The first end of the second plate 410 is hinged to the connecting member 411. To simplify the structure, the two second plates 410 are hinged to the same connecting member 411. Specifically, the first end of one second plate 410 is hinged to one end of the connecting member 411, and the first end of the other second plate 410 is hinged to the other end of the connecting member 411. The second end of the second plate 410 is hinged to the second end of the strut 320. When the strut 320 is folded, the second plate 410 is fixed to the rod bracket at the rear end of the truss boom 10.

[0092] Referring to FIG13 , the present application further provides a tensioning method, which is based on the tensioning mechanism of any of the above embodiments and includes:

[0093] In step S100 , the driving assembly 33 drives the strut assembly 32 to move to the open position, so that the second connecting assembly 40 is in a tensioned state.

[0094] When the second connecting assembly 40 is in the tensioned state, the second connecting assembly 40 limits the position of the brace assembly 32. The second connecting assembly 40 applies a backward pulling force to the brace assembly 32 to prevent the brace assembly 32 from moving forward when the truss boom 10 is subjected to force during use.

[0095] In step S200 , the displacement mechanism drives the first connecting assembly 31 to be in a tensioned state.

[0096] After the displacement mechanism drives the first connecting assembly 31 to be in a tensioned state, the first connecting assembly 31 is in a taut state, and the first connecting assembly 31 applies a pulling force forward to the strut assembly 32 so that the forces on both sides of the strut assembly 32 are balanced.

[0097] 14 , in a preferred embodiment of the present application, the driving assembly driving the strut assembly 32 to move to the open position includes:

[0098] S110 , the second driving member 333 drives the strut assembly 32 to rotate in a plane parallel to the truss boom 10 , so that the strut assembly 32 is perpendicular to the truss boom 10 .

[0099] Specifically, during the extension of the second cylinder, the second cylinder drives the strut 320 to rotate around the hinge point between the first end of the strut 320 and the second joint 331, so that the strut assembly 32 can rotate in a plane parallel to the truss boom 10. When the second cylinder is extended to its maximum length, the strut assembly 32 is perpendicular to the truss boom 10.

[0100] S120: The first driving member 332 drives the second joint 331 to rotate, so that the support rod assembly 32 moves to the open position.

[0101] Specifically, during the shortening of the first cylinder, the first cylinder drives the second joint 331 to rotate around the hinge point between the first end of the second joint 331 and the first joint 330, so as to realize the rotation of the strut assembly 32 within the amplitude variation plane. When the length of the first cylinder reaches the minimum length, the strut assembly 32 moves to the open position.

[0102] 15 , in a preferred embodiment of the present application, the displacement mechanism includes a hoisting mechanism 321 and a tightening mechanism 322 . The displacement mechanism drives the first connecting assembly 31 to be in a tensioned state, including:

[0103] S210, the hoisting mechanism 321 winds part of the steel wire rope 311 of the first connecting assembly 31 around the hoisting mechanism 321;

[0104] S220, the tightening mechanism 322 drives the steel wire rope 311 to move, so that the first connecting assembly 31 is in a tensioned state.

[0105] Since the stroke of the oil cylinder is short, before the oil cylinder stretches the wire rope 311, the existing start-up winch mechanism 321 is rotated, and part of the wire rope 311 is wound around the winch mechanism 321, so that the wire rope 311 is tensioned, and then the oil cylinder is controlled to shorten, so that the wire rope 311 is further stretched to reach a tensioned state.

[0106] The present application also provides a lifting equipment, which includes a lifting equipment body, a truss boom 10 and a tensioning mechanism for the truss boom according to any one of the above embodiments, wherein the truss boom 10 is connected to the lifting equipment body and the tensioning mechanism for the truss boom.

[0107] It should be noted here that the lifting equipment may be a crawler crane or a wheeled lattice boom crane, or other types of lifting equipment.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A tensioning mechanism for a truss boom, characterized in that: include: A brace assembly (32), wherein two brace assemblies (32) are symmetrically arranged on the top of the truss boom (10); a second connecting assembly (40) located between the free end of the brace assembly (32) and one end of the truss boom (10) and used to limit the position of the brace assembly (32); a first connecting assembly (31), located between the free end of the brace assembly (32) and the other end of the truss boom (10), and used for connecting to the displacement mechanism of the brace assembly (32); a driving assembly (33) for changing the position of the strut assembly (32); A third connecting assembly (333), the support rod assembly (32) is connected to the driving assembly (33) via the third connecting assembly (333).

2. The tensioning mechanism according to claim 1, characterized in that: Also includes: A mounting frame (20) is connected to the driving assembly (33), and the mounting frame (20) is connected to the support rod assembly (32) and the truss boom (10).

3. The tensioning mechanism according to claim 2, characterized in that: The drive assembly (33) comprises: A first joint (330) connected to the mounting frame (20); a second joint (331), wherein a first end of the second joint (331) is hingedly connected to the first joint (330); a first driving member (332) hingedly connected to the first joint (330) and the second end of the second joint (331), the first driving member (332) being used to drive the second joint (331) to rotate; A second driving member (333), the first end of the support rod assembly (32) is hinged to the second joint (331), and the second driving member (333) is hinged to the support rod assembly (32) and the second joint (331); the second driving member (333) is used to drive the support rod assembly (32) to rotate.

4. The tensioning mechanism according to claim 3, characterized in that: The first joint (330) correspondingly connected to the two support rod assemblies (32) is an integrated structure.

5. The tensioning mechanism according to claim 3, characterized in that: The truss-type boom (10) includes a lower arm (11) located at its end, and the strut assembly (32) includes a strut (320). A positioning groove (334) is provided at the first end of the strut (320). The positioning groove (334) is located on the side of the strut (320) facing away from the lower arm (11). When the strut (320) is in a working state, the second end of the second joint (331) abuts against the side wall and bottom wall of the positioning groove (334).

6. The tensioning mechanism according to claim 3, characterized in that: Limit blocks are provided on both sides of the truss boom (10); the strut assembly (32) includes a strut (320); the limit blocks are connected to the truss boom (10) via a connecting rod; when the strut (320) is in a working state, the strut (320) is located above the limit blocks, and the bottom surface of the first end of the strut (320) abuts against the limit blocks.

7. The tensioning mechanism according to any one of claims 1 to 6, characterized in that: The drive assembly (33) further comprises: The middle support rod (336), two of the middle support rods (336) are symmetrically arranged on the truss The front part of the boom (10) is connected to the corresponding first connecting assembly (31); and The third driving member (337) is hinged to the truss-type boom (10) and one end of the intermediate support rod (336) away from the first connecting assembly (31).

8. The tensioning mechanism according to claim 5, characterized in that: The truss boom (10) includes a lower boom (11) at its end, the first connecting assembly (31) includes a first pull plate (312), and two universal joints (12) are provided at one end of the truss boom (10) away from the lower boom (11), and the second end of the first pull plate (312) is hinged to the corresponding universal joint (12).

9. The tensioning mechanism according to claim 2, characterized in that: The mounting frame (20) and the truss-type boom (10) are detachably connected or integrally formed.

10. A tensioning method, the tensioning method being based on the tensioning mechanism according to any one of claims 1 to 9, characterized in that: The tensioning method comprises: The driving assembly (33) drives the support rod assembly (32) to move to an open position, so that the second connecting assembly (40) is in a tensioned state; The displacement mechanism drives the first connecting assembly (31) to be in a tensioned state.

11. The tensioning method according to claim 10, characterized in that: The driving assembly (33) drives the strut assembly (32) to move to the open position, comprising: The second driving member (333) drives the brace assembly (32) to rotate in a plane parallel to the truss boom (10) so that the brace assembly (32) is perpendicular to the truss boom (10); The first driving member (332) drives the second joint (331) to rotate, so that the support rod assembly (32) moves to an open position.

12. The tensioning method according to claim 10, characterized in that: The displacement mechanism comprises a hoisting mechanism (321) and a tightening mechanism (322), and the displacement mechanism drives the first connecting component (31) to be in a tensioned state, comprising: The hoisting mechanism (321) winds a portion of the steel wire rope (311) around the hoisting mechanism (321); The tightening mechanism (322) drives the steel wire rope (311) to move, so that the first connecting assembly (31) is in a tensioned state.

13. A lifting equipment, characterized in that: It comprises a lifting equipment body, a truss boom (10) and a tensioning mechanism according to any one of claims 1 to 9, wherein the truss boom (10) is connected to the lifting equipment body and the tensioning mechanism.

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