阅读说明：本技术 一种变强度臂架 (Variable-strength arm support ) 是由 李长青 陈栋梁 赵瑞学 陈志灿 王志明 于 2021-06-29 设计创作，主要内容包括：本发明公开了一种变强度臂架,包括从臂头端开始依次相连的小截面加长节、过渡段和大截面加长节,所述小截面加长节各处截面相同,所述大截面加长节各处截面相同,所述过渡段与所述小截面加长节相连的一端与所述小截面加长节截面相同,所述过渡段与所述大截面加长节相连的一端与所述大截面加长节截面相同,所述小截面加长节包括小截面低强段和小截面高强段,所述小截面高强段相对于所述小截面低强段远离臂头端,所述截面加长节包括大截面低强段和大截面高强段,所述大截面高强段相对于所述大截面低强段远离臂头端。本发明提供的一种变强度臂架,能够减少不必要的强度冗余,同时能够进一步提升产品轻量化设计。(The invention discloses a variable-strength arm support which comprises a small-section lengthened section, a transition section and a large-section lengthened section which are sequentially connected from an arm head end, wherein the sections of the small-section lengthened section are the same, the sections of the large-section lengthened section are the same, one end of the transition section connected with the small-section lengthened section is the same as the section of the small-section lengthened section, one end of the transition section connected with the large-section lengthened section is the same as the section of the large-section lengthened section, the small-section lengthened section comprises a small-section low-strength section and a small-section high-strength section, the small-section high-strength section is far away from the arm head end relative to the small-section low-strength section, the section lengthened section comprises a large-section low-strength section and a large-section high-strength section, and the large-section high-strength section is far away from the arm head end relative to the large-section low-strength section. The variable-strength arm support provided by the invention can reduce unnecessary strength redundancy and further improve the light-weight design of products.)

1. A variable-strength arm support is characterized in that: include from the arm head end the consecutive little section extension section, changeover portion (3) and big section extension section, little section high-strength section (2) for the arm head end is kept away from in little section low-strength section (1), the intensity of little section low-strength section (1) is less than the intensity of little section high-strength section (2), the section extension section is including big section low-strength section (4) and big section high-strength section (5), big section high-strength section (5) for the arm head end is kept away from in big section low-strength section (4), the intensity of big section low-strength section (4) is less than the intensity of big section high-strength section (5), the intensity of changeover portion (3) is greater than the intensity of little section high-strength section (2) and be less than the intensity of big section low-strength section (4).

2. The variable strength boom of claim 1, wherein: the cross sections of the small-section lengthened section are the same, the cross sections of the large-section lengthened section are the same, one end, connected with the small-section lengthened section, of the transition section (3) is the same as the cross section of the small-section lengthened section, and one end, connected with the large-section lengthened section, of the transition section (3) is the same as the cross section of the large-section lengthened section.

3. The variable strength boom of claim 2, wherein: and reinforcing plates are arranged on the small-section high-strength section (2) and the large-section high-strength section (5).

4. The variable strength boom of claim 2, wherein: and reinforcing ribs are arranged on the small-section high-strength section (2) and the large-section high-strength section (5).

5. The variable strength boom of claim 2, wherein: the steel pipe specification of the small-section high-strength section (2) is larger than that of the small-section low-strength section (1), and the steel pipe specification of the large-section high-strength section (5) is larger than that of the large-section low-strength section (4).

6. The variable strength boom of claim 1, wherein: the transition section (3) adopts a multi-transition-joint structure.

7. The variable strength boom of claim 1, wherein: the small-section low-strength section (1) and the large-section low-strength section (4) are all multi-strength combinations and respectively comprise a low-strength section close to the arm head end and a high-strength section far away from the arm head end.

Technical Field

The invention relates to a variable-strength arm support, and belongs to the technical field of truss arms.

Background

The truss type arm support structure is an important component of a large crane, particularly a long arm and large-amplitude working condition, and the truss arm is generally applied by the structural advantages of large rigidity and light weight. The maximum length of a truss type arm support applied to the crane industry exceeds one hundred meters, the truss type arm support generally consists of three types of structural members, namely a transition structure, an extension section and an arm head, and the arm length is changed by applying different numbers of the extension sections.

In order to ensure the interchangeability of the lengthening sections of the truss arms, the section of the lengthening section of a product with the same ton grade is the same as the specification of a pipe, but under the same working condition, the bending moment born by each lengthening section is greatly different. The extension section close to the arm head bears smaller bending moment, while the extension section far away from the arm head bears larger bending moment. When in design, in order to ensure the bearing capacity of the arm support, the section of the lengthened section and the specification of the pipe are designed according to the larger bending moment bearing capacity, so that the design strength of the lengthened section of the arm head section is redundant, and the integral lightweight degree of the arm support is low.

The truss arm of the existing product is basically divided into two or three lengthened sections to form a variable section design, and the structure of the arm support is optimized. The lengthened section close to the arm head is less stressed, and the strength is lower due to the adoption of a small-section design; the lengthened section far away from the arm head is stressed greatly, and the strength is high due to the adoption of a large-section design. The design has a certain effect on the light weight of the arm support, but the same section is designed according to the same specification of the pipe no matter the position is close to the front or the back, the unnecessary strength redundancy is caused, and the light weight degree is low.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a variable-strength arm support which can reduce unnecessary strength redundancy and can further improve the light-weight design of products.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

the utility model provides a variable strength cantilever crane, includes from the arm head end little cross-section extension section, changeover portion and the big cross-section extension section that links to each other in proper order, little cross-section high-strength section for the arm head end is kept away from to little cross-section low-strength section, the intensity of little cross-section low-strength section is less than the intensity of little cross-section high-strength section, cross-section extension section includes big cross-section low-strength section and big cross-section high-strength section, big cross-section high-strength section for the arm head end is kept away from to big cross-section low-strength section, the intensity of big cross-section low-strength section is less than the intensity of big cross-section high-strength section, the intensity of changeover portion is greater than the intensity of little cross-section high-strength section just is less than the intensity of big cross-section low-strength section.

The cross sections of the small-section lengthened section are the same, the cross sections of the large-section lengthened section are the same, the end, connected with the small-section lengthened section, of the transition section is the same as the cross section of the small-section lengthened section, and the end, connected with the large-section lengthened section, of the transition section is the same as the cross section of the large-section lengthened section.

And reinforcing plates are arranged on the small-section high-strength section and the large-section high-strength section.

And reinforcing ribs are arranged on the small-section high-strength section and the large-section high-strength section.

The steel pipe specification of the small-section high-strength section is larger than that of the small-section low-strength section, and the steel pipe specification of the large-section high-strength section is larger than that of the large-section low-strength section.

The transition section adopts a multi-transition-joint structure.

The low-strength section with the small cross section and the low-strength section with the large cross section are all multi-strength combinations and respectively comprise a low-strength section close to the arm head end and a high-strength section far away from the arm head end.

The invention has the beneficial effects that: according to the variable-strength arm support provided by the invention, the large-section lengthened section and the small-section lengthened section are further divided into the high-strength section and the low-strength section, the high-strength section and the low-strength section of the same section have the same section and are convenient to connect, the high-strength section is arranged at the farthest position away from the end of the arm of the same section, the stressed section is the largest in the same section and has the highest strength, the rest arm support sections with lower stress adopt the same low-strength design, the more refined variable-strength design of the arm support is realized, and the integral light-weight degree of the arm support is higher.

Drawings

Fig. 1 is a schematic view of the overall structure of a variable-strength boom of the present invention.

The reference numbers in the figures are as follows: 1-small section low-strength section; 2-a small-section high-strength section; 3-a transition section; 4-large section low-strength section; 5-large section high-strength section.

Detailed Description

The present invention is further described with reference to the accompanying drawings, and the following examples are only for clearly illustrating the technical solutions of the present invention, and should not be taken as limiting the scope of the present invention.

As shown in fig. 1, the invention provides a variable-strength arm support, which comprises a small-section elongated section, a transition section 3 and a large-section elongated section which are sequentially connected from an arm head end, wherein the sections of the small-section elongated section are the same, the sections of the large-section elongated section are the same, and the sections of a high-strength section and a low-strength section of the same section are the same, so that the connection is convenient. The end of the transition section 3 connected with the small section lengthening section is the same as the section of the small section lengthening section, and the end of the transition section 3 connected with the large section lengthening section is the same as the section of the large section lengthening section.

The small cross section lengthened section comprises a small cross section low-strength section 1 and a small cross section high-strength section 2, the small cross section high-strength section 2 is far away from the arm head end relative to the small cross section low-strength section 1, the cross section lengthened section comprises a large cross section low-strength section 4 and a large cross section high-strength section 5, and the large cross section high-strength section 5 is far away from the arm head end relative to the large cross section low-strength section 4. The high-strength section is arranged at the end of the arm furthest away from the same section, the stressed same-section lengthening section is the largest, the strength is the highest, and the rest arm support sections with lower stress adopt the same low-strength design.

The transition section adopts a multi-transition section structure. The small-section low-strength section and the large-section low-strength section are multi-strength combinations and respectively comprise a low-strength section close to the arm head end and a high-strength section far away from the arm head end.

The invention applies the equal-strength design mechanical principle, considers that the extension section of each section farthest from the arm head end bears the largest bending moment, and designs the part of the arm support independently, and the other arm support sections with lower stress adopt the same low-strength design, thereby realizing the more refined variable-strength design of the arm support, and the integral lightweight degree of the arm support is higher.

Specifically, the small-section high-strength section 2 and the large-section high-strength section 5 can be reinforced by adding a reinforcing plate; or reinforced by adding reinforcing ribs; or the specification of the steel pipe of the small-section high-strength section 2 is designed to be larger than that of the steel pipe of the small-section low-strength section 1, and the specification of the steel pipe of the large-section high-strength section 5 is designed to be larger than that of the steel pipe of the large-section low-strength section 4.

The above description is only of the preferred embodiments of the present invention, and it should be noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the invention and these are intended to be within the scope of the invention.