Crane load limiter and configuration method, configuration device

Abstract

This application discloses a crane load limiter and its configuration method and device. The crane load limiter includes a balance pulley, a wire rope, an eccentric shaft, a working spring, and a load sensor. The diameter of the balance pulley is determined based on the diameter of the wire rope. The diameter of the eccentric shaft is determined based on the force on the wire rope under rated lifting conditions, the support span of the balance pulley under rated lifting conditions, and the allowable stress of the eccentric shaft under rated lifting conditions. The parameters of the load sensor are determined based on the maximum measuring force calculated under the crane's rated lifting conditions. The mechanical parameters of the working spring are determined based on the crane's rated operating conditions, no-load conditions, and slack rope conditions. This application converts the actual load through the eccentric shaft, and the load sensor's measured value is converted into the actual value according to the design method, effectively reducing the working range of the load sensor and enabling the monitoring of larger loads without the need for specially customized sensors.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of cranes, in particular to a crane load limiter and a configuration method and device. BACKGROUND

[0002] Crane is frequently applied in engineering field. In production and application, vertical lifting of crane and horizontal movement of portal are generally used to realize extraction, transportation and unloading of materials.

[0003] In related technologies, load measurement of crane often adopts installation of load sensor on pulley shaft of fixed pulley block or balance pulley block to measure load of crane. In actual use, the above-mentioned measurement of load by installation of load sensor still has the following defects: (1) load sensor needs to be configured to monitor weight of object in real time in use. For large crane, load sensor selected is large and needs to be specially customized; (2) only whether crane is overloaded can be monitored and timely feedback is made, but timely feedback cannot be made for load mutation to zero caused by sudden situation, and the lifting mechanism of crane cannot be effectively protected; (3) if capacity of crane is large, hoisting is prone to be blocked. In the case of no overloading, the lifting mechanism after blocking is still working, and timely feedback cannot be made for the situation, which may cause fatal damage to core lifting parts of crane and even the whole crane, resulting in engineering accident.

[0004] Therefore, the above-mentioned technical problems in related technologies need to be solved. SUMMARY

[0005] The present application aims to solve one of the technical problems in related technologies. To this end, the present application provides a crane load limiter and a configuration method and device, which can reduce working range of load sensor and realize monitoring of large load.

[0006] According to an aspect of the present application, a crane load limiter is provided, which comprises a balance pulley, a steel wire rope, an eccentric shaft, a working spring and a load sensor,

[0007] The balance pulley is used to keep balance of load and the eccentric shaft, and diameter of the balance pulley is determined according to diameter of the steel wire rope;

[0008] The eccentric shaft is used to transmit gravity of load received by the load sensor according to preset proportion, and diameter of the eccentric shaft is determined according to stress of the steel wire rope in rated hoisting working condition, support span of the balance pulley in rated hoisting working condition and allowable stress of the eccentric shaft in rated hoisting working condition, and the preset proportion is determined by diameter of the eccentric shaft.

[0009] In one of the embodiments, the crane load limiter further comprises a slack rope switch and a balance lever, the slack rope switch controls the balance lever to cut off power supply when the load of the wire rope is less than the no-load weight, so that the crane stops working.

[0010] In one of the embodiments, the diameter of the balance pulley and the diameter of the wire rope satisfy the following relationship:

[0011] D1>18d1

[0012] Wherein, D1 is the diameter of the balance pulley, and d1 is the diameter of the wire rope.

[0013] In one of the embodiments, the diameter of the eccentric shaft, the stress of the wire rope under the rated lifting condition, the support span of the balance pulley under the rated lifting condition, and the allowable stress of the eccentric shaft under the rated lifting condition satisfy the following relationship:

[0014]

[0015] Wherein, D2 is the diameter of the eccentric shaft, Q 1为 The stress of the wire rope under the rated lifting condition, L is the support span of the balance pulley under the rated lifting condition, and σ is the allowable stress of the eccentric shaft under the rated lifting condition.

[0016] In one of the embodiments, the load sensor is used to measure the mass of the load, the parameters of the load sensor are determined according to the maximum measurement force calculated according to the rated lifting condition of the crane, and the parameters of the load sensor include the maximum measurement value of the load sensor, which is:

[0017]

[0018] Wherein, F1 is the maximum measurement value of the load sensor, S max is the maximum tension of the wire rope, p d is the eccentricity of the eccentric shaft, and P z is the total force arm.

[0019] In one of the embodiments, the mechanical parameters of the working spring are determined according to the rated condition, the no-load condition and the slack rope condition of the crane, and the mechanical parameters of the working spring include the stiffness, and the stiffness of the working spring is:

[0020]

[0021] h=h1-h n

[0022] Wherein, K1 is the stiffness of the working spring, P nP1 is the minimum load, h is the stroke of the working spring, h1 is the installation height of the working spring, h n is the working height of the working spring.

[0023] In one of the embodiments, the mechanical parameters of the working spring include the pitch, and the pitch of the working spring is:

[0024]

[0025] wherein t is the pitch of the working spring, n is the effective number of turns of the working spring, d is the diameter of the working spring, F j is the single-turn deformation of the working spring under the limit load.

[0026] According to an aspect of the embodiment of the present application, a configuration method of a crane load limiter is provided, and the method comprises:

[0027] determining the diameter of the steel wire rope according to the diameter of the balance pulley;

[0028] determining the diameter of the eccentric shaft according to the stress of the steel wire rope under the rated lifting working condition, the support span of the balance pulley under the rated lifting working condition, and the allowable stress of the eccentric shaft under the rated lifting working condition;

[0029] determining the parameters of the load sensor according to the maximum measurement force calculated according to the rated lifting working condition of the crane;

[0030] determining the mechanical parameters of the working spring according to the rated working condition, the no-load working condition, and the slack rope working condition of the crane.

[0031] In one of the embodiments, the method comprises:

[0032] determining the installation position of the electronic stroke switch according to the set stroke of the working spring.

[0033] According to an aspect of the embodiment of the present application, a crane load configuration device is provided, and the device comprises:

[0034] a steel wire rope diameter setting module, configured to determine the diameter of the steel wire rope according to the diameter of the balance pulley;

[0035] an eccentric shaft diameter setting module, configured to determine the diameter of the eccentric shaft according to the stress of the steel wire rope under the rated lifting working condition, the support span of the balance pulley under the rated lifting working condition, and the allowable stress of the eccentric shaft under the rated lifting working condition;

[0036] a load sensor setting module, configured to determine the parameters of the load sensor according to the maximum measurement force calculated according to the rated lifting working condition of the crane;

[0037] The working spring mechanical parameter setting module is configured to determine the mechanical parameters of the working spring according to the rated working condition, the empty load working condition and the slack rope working condition of the crane.

[0038] The crane load limiter provided by the embodiment of the application has the beneficial effects that the crane load limiter comprises a balance pulley, a steel wire rope, an eccentric shaft, a working spring and a load sensor, the diameter of the balance pulley is determined according to the diameter of the steel wire rope, the diameter of the eccentric shaft is determined according to the stress of the steel wire rope under the rated lifting working condition, the support span of the balance pulley under the rated lifting working condition and the allowable stress of the eccentric shaft under the rated lifting working condition, the parameters of the load sensor are determined according to the maximum measurement force calculated according to the rated lifting working condition of the crane, and the mechanical parameters of the working spring are determined according to the rated working condition, the empty load working condition and the slack rope working condition of the crane. The actual load is converted by the eccentric shaft, and the measurement value of the load sensor is converted into an actual value according to a design method, so that the working range of the load sensor is effectively reduced, and the monitoring of a large load is realized without the need of specially customized sensors.

[0039] Additional aspects and advantages of the application will be described in the following description, will become apparent from the following description, or will be learned. BRIEF DESCRIPTION OF DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description only constitute some embodiments of the application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0041] Figure 1 The overall structure schematic diagram of the crane load limiter provided by the embodiment of the application is shown in the figure;

[0042] Figure 2 The overall structure schematic diagram of the crane load limiter provided by the embodiment of the application is shown in the figure;

[0043] Figure 3 The flow chart of the crane load limiter configuration method provided by the embodiment of the application is shown in the figure;

[0044] Figure 4 The schematic diagram of the crane load limiter configuration device provided by the embodiment of the application is shown in the figure. DETAILED DESCRIPTION

[0045] In order to enable personnel in the technical field to better understand the scheme of the present application, the technical scheme in the embodiments of the present application will be clearly and completely described below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should fall within the scope of protection of the present application.

[0046] The terms "first", "second", "third", and "fourth" and the like in the description and in the claims of the present application and the drawings are used to distinguish different objects, rather than to describe a particular order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to the process, method, product or device.

[0047] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor does it necessarily refer to a separate or alternative embodiment in isolation or in combination with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with each other.

[0048] Crane is frequently applied in engineering field. In production application, the extraction, transportation and unloading of materials are generally realized through vertical lifting of the crane and horizontal movement of the portal.

[0049] In the related art, the load measurement of the crane often adopts the installation of a load sensor on the sheave shaft of a fixed pulley set or a balanced pulley set to measure the load of the crane. This kind of load measurement by installing a load sensor still has the following defects in the actual use process: (1) a load sensor needs to be configured to monitor the weight of the object in real time during use. For large cranes, the selected load sensor is large and needs to be specially customized; (2) only whether the crane is overloaded can be monitored and timely feedback is made, but timely feedback cannot be made for the case that the load suddenly becomes zero due to a sudden situation, and the hoisting mechanism of the crane cannot be effectively protected; (3) if the capacity of the crane is large, the hoisting is easy to be blocked, and in the case that there is no overload, the hoisting mechanism after being blocked is still working, and timely feedback cannot be made for such a situation, which may cause fatal damage to the core hoisting part of the crane, even the entire crane, and lead to an engineering accident.

[0050] In order to solve the above technical problems, the crane load limiter is provided.

[0051] Figure 1 A crane load limiter provided in the embodiment of the present application has the overall structure as shown in the figure, Figure 2 A crane load limiter provided in the embodiment of the present application has the overall structure as shown in the figure, the balance pulley and bearing seat position as shown in the figure, Figure 1 And Figure 2 In the figure: 101 is a steel wire rope, 102 is a bearing seat, 103 is a balance pulley, 104 is an eccentric shaft, 105 is a balance bar, 106 is an electronic travel switch, 107 is a compression spring, 107 is a load sensor, 108 is a steel wire rope, 201 is a bearing seat, and 202 is a balance pulley. As shown in the figure, Figure 1 And Figure 2 The crane load limiter includes a balance pulley, a steel wire rope, an eccentric shaft, a working spring and a load sensor. The diameter of the balance pulley is determined according to the diameter of the steel wire rope. The diameter of the eccentric shaft is determined according to the stress of the steel wire rope under the rated lifting working condition, the support span of the balance pulley under the rated lifting working condition and the allowable stress of the eccentric shaft under the rated lifting working condition. The parameters of the load sensor are determined according to the maximum measurement force calculated according to the rated lifting working condition of the crane. The mechanical parameters of the working spring are determined according to the rated working condition, the no-load working condition and the slack rope working condition of the crane. In the embodiment, the crane load limiter further includes a slack rope switch and a balance bar. The slack rope switch controls the balance bar to cut off the power supply when the load of the steel wire rope is less than the no-load weight, so that the crane stops working.

[0052] It should be noted that the center of the eccentric shaft in the embodiment is not at the center of the axis. The non-eccentric shaft can only drive the workpiece to rotate, but the eccentric shaft can transmit rotation and has the function of transmitting revolution. In addition, the load sensor in the embodiment is a sensitive device specially used for monitoring the load connection and disconnection of the power supply device output end. The load sensor is a general type device and can be applied to any power transformation device. Since a group of direct current power supply is required during work, it is most convenient to use it in an inverter with direct current power supply, which can directly use the direct current power supply. The basic function is to directly control the power supply on-off of the oscillation circuit in the inverter by using the load sensor, so as to realize automatic start and stop and achieve the purpose of energy saving. In the embodiment, the load sensor is arranged on the body of the crane and is used for measuring the tension of the platform connected with the steel wire rope.

[0053] In the embodiment, the diameter of the balance pulley is greater than the diameter of the steel wire rope, and the diameter of the balance pulley and the diameter of the steel wire rope satisfy the following inequality:

[0054] D1>18d1

[0055] D1 / d1>18, wherein D1 is the diameter of the balance pulley, and d1 is the diameter of the steel wire rope. It should be noted that the diameter of the balance pulley needs to be at least 18 times greater than the diameter of the steel wire rope, because the balance pulley itself occupies a certain volume, and the steel wire rope will drive the rotation of the balance pulley when sliding in the balance pulley, so that the balance pulley can keep stable operation.

[0056] In the embodiment, the diameter of the eccentric shaft, the stress of the steel wire rope under the rated lifting working condition, the supporting span of the balance pulley under the rated lifting working condition, and the allowable stress of the eccentric shaft under the rated lifting working condition satisfy the following inequality:

[0057]

[0058] wherein D2 is the diameter of the eccentric shaft, Q1 is the stress of the steel wire rope under the rated lifting working condition, l is the supporting span of the balance pulley under the rated lifting working condition, and sigma is the allowable stress of the eccentric shaft under the rated lifting working condition.

[0059] In the embodiment, the parameters of the load sensor include the maximum measurement value of the load sensor, and the maximum measurement value of the load sensor is:

[0060]

[0061] wherein F1 is the maximum measurement value of the load sensor, S max is the maximum tension of the steel wire rope, p d is the eccentricity of the eccentric shaft, and P z is the total force arm.

[0062] The working spring in the embodiment includes an end and tight flat type cylindrical helical compression spring, the mechanical parameters of the working spring include stiffness, and the stiffness of the working spring is:

[0063]

[0064] h=h1-h n

[0065] wherein K1 is the stiffness of the working spring, P n is the maximum load, P1 is the minimum load, h is the stroke of the working spring, h1 is the installation height of the working spring, and h n is the working height of the working spring. In addition, the mechanical parameters of the working spring include pitch, and the pitch of the working spring is:

[0066]

[0067] Wherein, t is the pitch of the working spring, n is the effective number of turns of the working spring, d is the diameter of the working spring, F j is the single-turn deformation of the working spring under the limit load.

[0068] The application also discloses a configuration method of a crane load limiter, Figure 3 A flowchart of a configuration method of a crane load limiter provided by an embodiment of the application is shown in Figure 3 The configuration method of the crane load limiter specifically comprises the following steps:

[0069] S301, determining the diameter of the steel wire rope according to the diameter of the balance pulley.

[0070] S302, determining the diameter of the eccentric shaft according to the stress of the steel wire rope under the rated lifting working condition, the supporting span of the balance pulley under the rated lifting working condition and the allowable stress of the eccentric shaft under the rated lifting working condition.

[0071] S303, determining the parameters of the load sensor according to the maximum measurement force calculated under the rated lifting working condition of the crane.

[0072] S304, determining the mechanical parameters of the working spring according to the rated working condition, the no-load working condition and the slack rope working condition of the crane.

[0073] Exemplarily, the embodiment of the crane is specifically described by taking the crane applied in production as an example, and the embodiment is specifically as follows:

[0074] Suppose that the lifting rated capacity of a crane is 1250kN, the self weight of the lifting appliance is 130kN, the pulley set ratio is 6, the drum is a double drum, and the lifting mechanism efficiency is 0.92. The maximum tension of the steel wire rope is:

[0075]

[0076] The diameter of the galvanized steel wire rope is selected to be 34mm.

[0077] Step one, determining the diameter of the balance pulley according to the diameter d1 of the steel wire rope of the lifting mechanism, that is, D1>18d1=612mm, so the diameter of the balance pulley can be selected to be 630mm according to the diameter of the steel wire rope;

[0078] Step two, the stress of the steel wire rope under the rated lifting working condition of the steel wire rope is Q1=Smax=125kN, the supporting span of the balance pulley is L=320mm, the material of the eccentric shaft is 45 steel, the allowable stress is σ=150Mpa, the diameter D2 of the eccentric shaft is determined, and the diameter is 150mm, so that:

[0079]

[0080] Step three, according to the rated lifting conditions of the lifting mechanism to calculate the maximum measured force:

[0081]

[0082] Select the maximum measured force of the load cell to be 20kN;

[0083] Step four, according to the rated working condition, the empty load condition, and the loose rope condition, respectively, to design the mechanical parameters and geometric parameters of the working spring.

[0084] It needs to be explained that when the rated load, the force of the steel wire rope on the balance pulley:

[0085]

[0086] When empty, the force of the steel wire rope on the balance pulley:

[0087]

[0088] When the rope is loose, the force of the steel wire rope on the balance pulley (only including the weight of the steel wire rope)

[0089]

[0090] The eccentric moment generated by the steel wire rope:

[0091] M max = 2S2P z = 2x11.77x20 = 470.8KN·mm

[0092] M min = 2S3P z = 2x2.26x20 = 90.4KN·mm

[0093] Force at the end of the balance bar:

[0094]

[0095]

[0096] Set the spring travel h = 5mm, the spring adopts the end tight grinding flat cylindrical spiral compression spring, the material is 60Si2Mn cold rolling, each end supports a circle, the maximum load Pn = 1.0kN, the minimum load P1 = 0.2kN. The initial calculation of spring stiffness: K1 = (Pn-P1) / h = 160N / mm;

[0097] The primary spring parameters are as follows: spring material diameter d2=8 mm, spring center diameter D2=38 mm, spring stiffness K'=737 N / mm, calculated spring effective number of turns n=K' / K1=4.6, according to the standard number of turns table for compression springs, n=4.5 is selected, total number of turns n1=n+2=6.5, spring stiffness K1=K' / n=163.8 N / mm;

[0098] The spring pitch is as follows: according to the table, the single-turn deformation under the working limit load is fj=3.7, the deformation under the working limit load is Fj=nfj=4.5*3.7=16.65 mm, and the pitch t=Fj / n+d2=3.7+8=11.7 mm;

[0099] The spring free height is as follows: H0=nt+1.5d=4.5*11.7+1.5*8=64.65 mm, and 65 mm is taken;

[0100] The spring installation height is as follows: H1=H0-P1 / K1=65-200 / 163.8=63.8 mm

[0101] The spring working height is as follows: Hn=H0-Pn / K1=65-1000 / 163.8=58.9 mm

[0102] The spring working stroke is as follows: H=H1-Hn=4.9 mm

[0103] The spring helix angle is as follows: a=arctan(t / pD)=5.6°

[0104] The spring unwound length is as follows: L=pDn / cos a=779.3 mm

[0105] The spring compressed length is as follows: HB=(n+1.5)d=48 mm

[0106] The spring compressed load is as follows: PB=K1(H0-HB)=2785 N

[0107] According to the above calculation results, the parameters of the crane load limiter of the application are designed, and the actual load is converted.

[0108] The crane load limiter provided in the application has the following advantages: the actual load is converted by an eccentric shaft, and the measured value of the load sensor is converted into an actual value according to the design method, effectively reducing the working range of the load sensor, realizing the monitoring of a larger load without the need for special customization of the sensor; while monitoring whether the crane hoisting weight is overloaded, timely feedback can be made to the situation where the load suddenly changes to zero due to sudden situations, effectively protecting the hoisting mechanism of the crane; feedback can be made at the moment when the hoisting mechanism is blocked, protecting the core components of the hoisting mechanism and avoiding engineering accidents.

[0109] The application also provides a crane load configuration device, which comprises Figure 4 as shown in the figure, the device comprises:

[0110] A steel wire rope diameter setting module 401 is configured to determine the diameter of the steel wire rope according to the diameter of the balance pulley.

[0111] An eccentric shaft diameter setting module 402 is configured to determine the diameter of the eccentric shaft according to the stress of the steel wire rope under a rated lifting working condition, the support span of the balance pulley under the rated lifting working condition, and the allowable stress of the eccentric shaft under the rated lifting working condition.

[0112] A load sensor setting module 403 is configured to determine the parameters of the load sensor according to the maximum measured force calculated according to the rated lifting working condition of the crane.

[0113] A working spring mechanical parameter setting module 404 is configured to determine the mechanical parameters of the working spring according to the rated working condition, the no-load working condition, and the slack rope working condition of the crane.

[0114] It can be seen that the content in the method embodiment is applicable to the device embodiment, the device embodiment specifically implements the same functions as the method embodiment, and achieves the same beneficial effects as the method embodiment.

[0115] In some alternative embodiments, the functions / operations mentioned in the block diagram can not occur in the order mentioned in the operation diagram. For example, depending on the functions / operations involved, two blocks shown in succession can actually be performed at substantially the same time or the blocks can sometimes be performed in reverse order. In addition, the embodiments presented and described in the flowcharts of the present application are provided by way of example, with the purpose of providing a more comprehensive understanding of the technology. The disclosed method is not limited to the operations and logical flows presented herein. Alternative embodiments are contemplated in which the order of various operations is changed and in which sub-operations described as part of larger operations are independently performed.

[0116] Furthermore, although the present application is described in the context of functional modules, it is understood that one or more of the functions and / or features can be integrated in a single physical device and / or software module, or one or more functions and / or features can be implemented in separate physical devices or software modules. It is also understood that a detailed discussion of the actual implementation of each module is unnecessary to an understanding of the present application. Rather, the actual implementation is within the routine skill of engineers familiar with the property, function and internal relationships of the various functional modules disclosed herein. Accordingly, the present application is not limited to the specific details of the functional modules described herein. Rather, it is understood that the skilled artisan, using ordinary skill in the art, can implement the application as taught in the claims without undue experimentation. It is also understood that the particular concepts disclosed are merely illustrative and that the scope of the present application is defined by the appended claims and their equivalents.

[0117] If the functions are implemented in software, the functions can be stored in or implemented as one or more computer program products. The computer program product can be stored in a computer readable medium, which can include, but is not limited to, RAM, ROM, electrically programmable ROM (EPROM or EEPROM), flash memory, or a magnetic or optical card, or any suitable device used for storing a computer program and data. The computer program product can also be propagated via an electric signal or an optical signal transmitted via an electromagnetic carrier.

[0118] The logic and / or steps represented in the flowcharts and / or otherwise described herein, for example, can be embodied in non-transitory computer-readable media, which can be executed by an instruction execution system, apparatus, or device such as a computer-based system, processor, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. In the context of this specification, a "computer-readable medium" can be any means that can contain, store, communicate, propagate or transport the program for use by or in connection with the instruction execution system, apparatus, or device.

[0119] More specific examples (a non-exhaustive list) of the computer-readable medium include the following: an electrical connection (electronic) having one or more wires, a portable computer diskette (magnetic), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can also be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, for example, via optical scanning of the paper or other medium, then compiled, interpreted, or otherwise processed in a suitable manner, if necessary, and then stored in a computer memory.

[0120] It should be understood that throughout the application, where a process or method is described, the process or method can be embodied in hardware, software, firmware, or any combination thereof. Where the process or method is embodied in software, the software can be stored in a memory and executed by a suitable instruction execution system. For example, if embodied in hardware, and in another embodiment, the hardware can include any or a combination of the following: discrete logic circuitry having logic gates for implementing logic functions upon data signals, application specific integrated circuitry designed to perform an individual function or a combination of multiple functions, a programmable gate array (PGA), a field programmable gate array (FPGA), and / or the like.

[0121] In the above-description of various embodiments of the present application, no distinction is made between the use of the terms "about" and "approximately." It is to be understood that the terms "about" and "approximately" can be used interchangeably herein to generally refer to a range of numbers that one of skill in the art would consider equivalent to the recited value (e.g., having the same function or result). In some embodiments, "about" can indicate an acceptable quality, rotation, and / or quantity. In certain

[0122] While the embodiments of the present application have been shown and described with reference to various embodiments thereof, it will be understood that various additions, modifications and substitutions can be made by those skilled in the art to the embodiments without departing from the spirit and scope of the present application as defined in the accompanying claims and their equivalents.

[0123] The above embodiments are only used to illustrate the technical solutions of the present application, not limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. Crane load limiter, characterized in that The crane load limiter comprises a counterweight pulley, a wire rope, an eccentric shaft, a working spring and a load sensor, The counterweight pulley is used to keep the balance of the load and the eccentric shaft, and the diameter of the counterweight pulley is determined according to the diameter of the wire rope; The eccentric shaft is used to transfer the gravity of the load to the load sensor in a preset proportion, so that the load sensor can determine the load of the wire rope; the diameter of the eccentric shaft is determined according to the stress of the wire rope under the rated lifting condition, the support span of the counterweight pulley under the rated lifting condition and the allowable stress of the eccentric shaft under the rated lifting condition, and the preset proportion is determined by the diameter of the eccentric shaft; the working spring is arranged between the eccentric shaft and the load sensor; The crane load limiter further comprises a loose rope switch and a balance bar, and the loose rope switch controls the balance bar to cut off the power supply when the load of the wire rope is less than the empty load weight, so that the crane stops working.

2. Crane load limiter according to claim 1, characterized in that The diameter of the counterweight pulley and the diameter of the wire rope satisfy the following relationship: D1>18d1 Wherein, D1 is the diameter of the counterweight pulley, and d1 is the diameter of the wire rope.

3. Crane load limiter according to claim 1, characterized in that The diameter of the eccentric shaft and the stress of the wire rope under the rated lifting condition, the support span of the counterweight pulley under the rated lifting condition and the allowable stress of the eccentric shaft under the rated lifting condition satisfy the following relationship: Wherein, D2 is the diameter of the eccentric shaft, Q1 is the stress of the wire rope under the rated lifting condition, L is the support span of the counterweight pulley under the rated lifting condition, and sigma is the allowable stress of the eccentric shaft under the rated lifting condition.

4. The crane load limiter of claim 1, wherein, The load sensor is used to measure the mass of the load, and the parameters of the load sensor are determined according to the maximum measurement force calculated according to the rated lifting condition of the crane, and the parameters of the load sensor include the maximum measurement value of the load sensor, and the maximum measurement value of the load sensor is: where F1 is the maximum measurement of the load sensor, S max is the maximum tension of the wire rope, p d is the eccentricity of the eccentric shaft, P z is the total arm.

5. The crane load limiter of claim 1, wherein, The mechanical parameters of the working spring are determined according to the rated condition, the empty load condition and the loose rope condition of the crane, and the mechanical parameters of the working spring include the stiffness, and the stiffness of the working spring is: Wherein, K1 is the stiffness of the working spring, P n is the maximum load, P1 is the minimum load, h is the stroke of the working spring, h1 is the installation height of the working spring, h n is the working height of the working spring.

6. The crane load limiter of claim 1, wherein, The mechanical parameters of the working spring include the pitch, and the pitch of the working spring is: wherein t is the pitch of the working spring, n is the effective number of turns of the working spring, d is the diameter of the working spring, F j is the single-turn deformation of the working spring at the limit load.

7. A method of configuring a load limiter for a crane, for configuring a load limiter for a crane as claimed in any one of claims 1-6, characterized in that, The method comprises: determining the diameter of the wire rope according to the diameter of the counterweight pulley; determining the diameter of the eccentric shaft according to the stress of the wire rope under the rated lifting condition, the support span of the counterweight pulley under the rated lifting condition and the allowable stress of the eccentric shaft under the rated lifting condition; determining the parameters of the load sensor according to the maximum measurement force calculated according to the rated lifting condition of the crane; determining the mechanical parameters of the working spring according to the rated condition, the empty load condition and the loose rope condition of the crane.

8. A method of configuring a crane load limiter according to claim 7, characterized in that, The method comprises: determining the installation position of the electronic stroke switch according to the setting stroke of the working spring.

9. Arrangement for configuring a crane load limiter according to any one of claims 1-6, characterized in that, The device comprises: a wire rope diameter setting module for determining the diameter of the wire rope according to the diameter of the counterweight pulley; The eccentric shaft diameter setting module is configured to determine the diameter of the eccentric shaft according to the force of the steel wire rope under the rated lifting working condition, the support span of the balance pulley under the rated lifting working condition, and the allowable stress of the eccentric shaft under the rated lifting working condition. The load sensor setting module is configured to determine the parameters of the load sensor according to the maximum measurement force calculated according to the rated lifting working condition of the crane. The working spring mechanical parameter setting module is configured to determine the mechanical parameters of the working spring according to the rated working condition, the no-load working condition and the slack rope working condition of the crane.

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