A calculation method for determining the load size of the truck crane outriggers

Abstract

The present invention provides a calculation method for determining the load size of a car crane outrigger, which belongs to the technical field of mechanical construction and comprises the following steps: S1, establishing a calculation model, G1 is the deadweight of the car crane, G2 is the deadweight of the turntable part, the weight of the boom is G3, the weight of the hanging object is F, the working amplitude of the boom is L, the distance between the front and rear outriggers is b, the lateral distance between the outriggers is a, the distance between the center of gravity of the car and the axis of the front outrigger is c, the four outriggers are A, B, C and D, and the load borne by the four outriggers is N A 、N B 、N C and N D ; S2, load calculation, calculate the outrigger reaction force N generated by the flatbed truck's deadweight A1 、N B1 、N C1 and N D1 , establish the equilibrium equation. It solves the problem that when the bearing capacity is poor or the floor is operated, the safety can only be provided by soil reinforcement and the lower part of the floor returning to the top, the error is huge, the advantage is excessively improved safety, resulting in great waste.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical construction, and in particular relates to a calculation method for determining the load size of a vehicle crane outrigger. Background Art

[0002] The existing technology often evaluates the ground bearing capacity through the experience of the crane driver. When the bearing capacity is poor or the floor is operated, safety can only be provided by reinforcing the soil and returning the lower part of the floor. The error is huge, and the advantage is excessively improved safety, resulting in great waste. In order to solve the load size of the outriggers of the truck crane on the ground during the lifting process, a convenient and simple calculation method for determining the load size of the outriggers of the truck crane is provided, so as to compare it with the ground bearing capacity and verify the safety of the lifting operation. Summary of the invention

[0003] The embodiment of the present invention provides a calculation method for determining the load size of the vehicle crane legs, which solves the problem that when encountering poor bearing capacity or floor operations, safety can only be provided by reinforcing the soil and returning the lower part of the floor, the error is very large, and the advantage is excessively improved safety, resulting in great waste.

[0004] In view of the above problems, the technical solution proposed by the present invention is:

[0005] The present invention provides a calculation method for determining the load size of a vehicle crane outrigger, comprising the following steps:

[0006] S1, establish the calculation model, G1 is the deadweight of the truck crane, G2 is the deadweight of the turntable, the weight of the boom is G3, the weight of the object is F, the working range of the boom is L, the distance between the front and rear legs is b, the lateral distance between the legs is a, the distance between the center of gravity of the truck and the axis of the front legs is c, the four legs are A, B, C and D, and the load borne by the four legs is N A 、N B 、N C and N D ;

[0007] S2, load calculation, calculate the outrigger reaction force N generated by the flatbed truck's deadweight A1 、N B1 、N C1 and N D1 , establish the equilibrium equation as follows:

[0008]

[0009]

[0010] The outrigger reaction force N generated by the deadweight of the turntable A2 、N B2 、NC2 and N D2 ,

[0011]

[0012] The reaction force of the outriggers borne by the boom and the weight is N A3 、N B3 、N C3 and N D3 , the deadweight of the boom and the load of the hanging objects can be directly converted into the gravity load and bending moment load acting on the center of the turntable, and the gravity load and bending moment load are calculated separately;

[0013] The gravity load is F z =G3+F

[0014] The bending moment load is

[0015] Calculate the outrigger reaction force N under the action of Fz A3F 、N B3F 、N C3F and N D3F ,

[0016]

[0017] S3, calculate M Z The outrigger reaction force under action N A3M 、M B3M 、N C3M and N D3M ,

[0018] The bending moment M Z Decomposed into bending moments M in the x and y directions Zx and M Zy , whose size is

[0019] M Zx =M Z cosθ

[0020] M Zy =M Z sinθ

[0021] First calculate the outrigger reaction force N generated by the bending moment in the x direction A3Mx 、N B3Mx 、N C3Mx and N D3Mx , distribute the bending moment according to the bending moment distribution method, the AB axis stiffness is to calculate the bending moment distribution coefficient μ of each leg respectively,

[0022]

[0023] The bending moment M distributed between the AB axis and the CD axis can be obtainedA-B and M C-D

[0024]

[0025] According to the moment balance of the AB axis and the CD axis and the vertical load balance, the following formula can be obtained:

[0026] N B3Mx +N A3Mx =0;

[0027] N C3Mx +N D3Mx =0;

[0028] To obtain,

[0029] Similarly, the outrigger reaction force N generated by the bending moment in the y direction can be obtained: A3My 、N B3My 、N C3Mt and N D3My ,

[0030]

[0031] Superimpose the above loads and substitute Fz and M Z The reaction force of the outriggers under the action of the weight and the boom can be obtained:

[0032]

[0033]

[0034] The final reaction force of the truck crane outriggers can be obtained by superimposing the loads. The specific formula is as follows:

[0035]

[0036] ≥0 means that there is no tension between the outrigger and the ground.

[0037] As a preferred technical solution of the present invention, in step S1, the load is N A 、N B 、N C and N D It mainly consists of 3 parts:

[0038] a. Load generated by the flatbed truck’s own weight;

[0039] b. Load generated by the deadweight of the turntable;

[0040] c. Loads generated by the boom and weight;

[0041] By calculating the outrigger loads under the above loads separately and performing algebraic superposition, the loads at each outrigger location can be found.

[0042] As a preferred technical solution of the present invention, in step S3, if a load is generated during the calculation, it means that the mobile crane may be in an unsafe state. The load on the leg part can be set to 0, and the moment and load balance formula can be used to re-check the safety of the mobile crane under working conditions.

[0043] As a preferred technical solution of the present invention, the load calculation formula of the truck crane, G1, G2, G3, a, b1, b2, b and c are constant values ​​of the attributes of the truck crane itself, and F and L are fixed parameters during the lifting operation. Therefore, it is only necessary to determine the weight and its running trajectory to determine the load change and extreme value of the truck crane legs.

[0044] Compared with the prior art, the beneficial effects of the present invention are:

[0045] (1) The present invention clarifies the bending moment distribution of the four legs of the truck crane through the bending moment distribution method;

[0046] (2) The present invention uses a load superposition method to superimpose the effects of the truck crane load, the transfer platform load, the boom load and the heavy load to obtain the total load of the outrigger when all loads act simultaneously;

[0047] (3) The present invention directly clarifies the load calculation formula for the four legs, which can be solved by directly substituting parameter values ​​to obtain the leg bearing capacity, and clarifies the requirement that the load is greater than 0, thus simply and clearly giving the safety performance requirements of the truck crane itself.

[0048] (4) The present invention can obtain calculated values ​​through the loads of the four legs, which can facilitate good mechanical comparison and verification with the bearing capacity of the working surface, and can effectively avoid excessive reinforcement and economic waste;

[0049] (5) The calculation parameters of the present invention are simple and the calculation formula is concise. The load of each leg can be directly calculated, which is convenient for checking the various working conditions of the mobile crane and the self-safety. The load size and position of the calculation result are clear and can be directly used to verify the bearing capacity of the site. When studying the lifting plan, the position of the mobile crane can be arranged and inspected more conveniently. The calculation formula can be changed according to the number of legs, and the applicability is good.

[0050] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A common schematic diagram of a vehicle hoisting operation condition is a calculation method for determining the load size of a vehicle crane outrigger disclosed in the present invention;

[0052] Figure 2 The invention discloses a schematic diagram of the change of the supporting leg bearing capacity and the boom angle under the action of a calculation method for determining the load size of the supporting legs of a vehicle crane. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0055] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0056] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0057] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0058] Embodiment 1

[0059] See attached Figure 1 As shown, the present invention provides a technical solution: a calculation method for determining the load size of the vehicle crane outrigger, comprising the following steps:

[0060] S1, establish the calculation model, G1 is the deadweight of the truck crane, G2 is the deadweight of the turntable, the weight of the boom is G3, the weight of the object is F, the working range of the boom is L, the distance between the front and rear legs is b, the lateral distance between the legs is a, the distance between the center of gravity of the truck and the axis of the front legs is c, the four legs are A, B, C and D, and the load borne by the four legs is N A 、N B 、N C and N D , the load is N A 、N B 、N C and N D It mainly consists of 3 parts:

[0061] a. Load generated by the flatbed truck’s own weight;

[0062] b. Load generated by the deadweight of the turntable;

[0063] c. Loads generated by the boom and weight;

[0064] Calculate the outrigger loads under the above loads respectively and perform algebraic superposition to find the loads at each outrigger position;

[0065] S2, load calculation, calculate the outrigger reaction force N generated by the flatbed truck's deadweight A1 、N B1 、N C1 and N D1 , establish the equilibrium equation as follows:

[0066]

[0067] The outrigger reaction force N generated by the deadweight of the turntable A2 、N B2 、N C2 and N D2 ,

[0068]

[0069] The reaction force of the outriggers borne by the boom and the weight is N A3 、N B3 、N C3 and N D3 , the deadweight of the boom and the load of the hanging objects can be directly converted into the gravity load and bending moment load acting on the center of the turntable, and the gravity load and bending moment load are calculated separately;

[0070] The gravity load is F z =G3+F

[0071] The bending moment load is

[0072] Calculate the outrigger reaction force N under the action of Fz A3F 、N B3F 、N C3F and N D3F ,

[0073]

[0074] S3, calculate M Z The outrigger reaction force under action N A3M 、N B3M 、N C3M and N D3M ,

[0075] The bending moment M Z Decomposed into bending moments M in the x and y directions Zx and M Zy , whose size is

[0076] M Zx =M Z cosθ

[0077] M Zy =M Z sinθ

[0078] First calculate the outrigger reaction force N generated by the bending moment in the x direction A3Mx 、N B3Mx 、N C3Mx and N D3Mx , distribute the bending moment according to the bending moment distribution method, the AB axis stiffness is to calculate the bending moment distribution coefficient μ of each leg respectively,

[0079]

[0080] The bending moment M distributed between the AB axis and the CD axis can be obtained A-B and M C-D

[0081]

[0082] According to the moment balance of the AB axis and the CD axis and the vertical load balance, the following formula can be obtained:

[0083] N B3Mx +N A3Mx =0;

[0084] N C3Mx +N D3Mx =0;

[0085] To obtain,

[0086] Similarly, the outrigger reaction force N generated by the bending moment in the y direction can be obtained: A3My 、N B3My 、N C3My and N D3My ,

[0087]

[0088] Superimpose the above loads and substitute Fz and M Z The reaction force of the outriggers under the action of the weight and the boom can be obtained:

[0089]

[0090] The final reaction force of the truck crane outriggers can be obtained by superimposing the loads. The specific formula is as follows:

[0091]

[0092] ≥0 means that there is no tension between the outrigger and the ground.

[0093] The embodiment of the present invention is also implemented through the following technical solutions.

[0094] In an embodiment of the present invention, in step S3, if a load is generated during calculation, it means that the mobile crane may be in an unsafe state, and the load on the leg part can be set to 0, and the safety of the mobile crane under working conditions can be re-calculated using the bending moment and load balance formula.

[0095] In an embodiment of the present invention, according to the load calculation formula of the truck crane, G1, G2, G3, a, b1, b2, b and c are constant values ​​of the attributes of the truck crane itself, and F and L are fixed parameters during the lifting operation. Therefore, it is only necessary to determine the weight and its running trajectory to determine the load change and extreme value of the truck crane legs.

[0096] like Figure 2 As shown, taking an ordinary 25-ton truck crane as an example, the outrigger loads under working conditions of the truck crane are studied. G1, G2, G3, a, b1, b2, b and c are 260kN, 30kN, 10kN, 6.1m, 2.68m, 2.68m, 5.36m, 0.79m respectively. The weight of the hoisted object F is 40kN. The working range L=6m. The loads of each outrigger can be calculated using the calculation formula to obtain each angle.

[0097] In addition, the load parameters of this calculation model should be taken according to the manual of the truck crane and the actual situation; when calculating, it is advisable to calculate the load size of all legs at the same time, and check whether there is a situation where the leg load is less than 0; in order to avoid unexpected situations, the safety factor should be appropriately increased when verifying the bearing capacity of the working surface; when the truck crane is operating, it should be carried out strictly in accordance with national laws, regulations and construction plan requirements; when our company calculates, the 4 legs are calculated in the same way as the profile. If the actual truck crane legs are not uniform, the bending moment distribution of the legs can be redistributed and calculated according to their stiffness.

[0098] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0099] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of protection of the present disclosure. The attached method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0100] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0101] Those skilled in the art will also appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments herein can all be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above around their functions. Whether such functions are implemented as hardware or software depends on specific applications and the design constraints imposed on the entire system. A skilled person can implement the described functions in an alternative manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of the present disclosure.

[0102] The steps of the method or algorithm described in conjunction with the embodiments herein may be directly embodied as hardware, a software module executed by a processor, or a combination thereof. The software module may be located in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a mobile disk, a CD-ROM, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and the storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and the storage medium may also be present in a user terminal as discrete components.

[0103] For software implementation, the techniques described in this application can be implemented with modules (e.g., procedures, functions, etc.) that perform the functions described in this application. These software codes can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or outside the processor. In the latter case, it is coupled to the processor in a communication manner via various means, which are well known in the art.

[0104] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

Claims

1. A calculation method for determining the load size of a truck crane outrigger, characterized in that: The following steps are involved: S1, establish the calculation model, G1 is the deadweight of the truck crane, G2 is the deadweight of the turntable, the weight of the boom is G3, the weight of the object is F, the working range of the boom is L, the distance between the front and rear legs is b, the lateral distance between the legs is a, the distance between the center of gravity of the truck and the axis of the front legs is c, the four legs are A, B, C and D, and the reaction force produced by the four legs is N A 、N B 、N C and N D ; S2, load calculation, calculate the outrigger reaction force N generated by the flatbed truck's deadweight A1 、N B1 、N C1 and N D1 , establish the equilibrium equation as follows: The outrigger reaction force N generated by the deadweight of the turntable A2 、N B2 、N C2 and N D2 , The reaction force of the outriggers borne by the boom and the weight is N A3 、N B3 、N C3 and N D3 , the deadweight of the boom and the load of the hanging objects can be directly converted into the gravity load and bending moment load acting on the center of the turntable, and the gravity load and bending moment load are calculated separately; The gravity load is F z =G3+F The bending moment load is Calculate the outrigger reaction force N under the action of Fz A3F 、N B3F 、N C3F and N D3F , S3, calculate M Z The outrigger reaction force under action N A3M 、N B3M 、N C3M and N D3M , The bending moment M Z Decomposed into bending moments M in the x and y directions Zx and M Zy , whose size is M Zx =M Z cosθ M Zy =M Z sinθ First calculate the outrigger reaction force N generated by the bending moment in the x direction A3Mx 、N B3Mx 、N C3Mx and N D3Mx , distribute the bending moment according to the bending moment distribution method, and calculate the bending moment distribution coefficient μ of each leg respectively, The bending moment M distributed between the AB axis and the CD axis can be obtained A-B and M C-D According to the moment balance of the AB axis and the CD axis and the vertical load balance, the following formula can be obtained: N B3Mx +N A3Mx =0; N C3Mx +N D3Mx =0; To obtain, Similarly, the outrigger reaction force N generated by the bending moment in the y direction can be obtained: A3My 、N B3My 、N C3My and N D3My , Superimpose the above loads and substitute Fz and M Z The reaction force of the outriggers under the action of the weight and the boom can be obtained: The final reaction force of the truck crane outriggers can be obtained by superimposing the loads. The specific formula is as follows: ≥0 means that there is no tension between the outrigger and the ground.

2. A calculation method for determining the load size of a truck crane outrigger according to claim 1, characterized in that: In step S1, the load is N A 、N B 、N C and N D It mainly consists of 3 parts: a. Load generated by the flatbed truck’s own weight; b. Load generated by the deadweight of the turntable; c. Loads generated by the boom and weight; By calculating the outrigger loads under the above loads separately and performing algebraic superposition, the loads at each outrigger location can be found.

3. A calculation method for determining the load size of a truck crane outrigger according to claim 2, characterized in that: In step S3, if a load is generated during the calculation, it means that the mobile crane may be in an unsafe state. The load on the leg can be set to 0, and the safety of the mobile crane under working conditions can be recalculated using the bending moment and load balance formula.

4. A calculation method for determining the load size of a truck crane outrigger according to claim 1, characterized in that: According to the load calculation formula of the truck crane, G1, G2, G3, a, b1, b2, b and c are constant values ​​of the truck crane itself, and F and L are fixed parameters during the lifting operation. Therefore, it is only necessary to determine the weight and its running trajectory to determine the load change and extreme value of the truck crane legs.

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