CN-122009068-A - Liquid expansion forming type steel energy-absorbing box structure and manufacturing method thereof

CN122009068ACN 122009068 ACN122009068 ACN 122009068ACN-122009068-A

Abstract

The invention provides a liquid expansion forming type steel energy-absorbing box structure which is provided with a tubular structure with a convex octagonal cross section, wherein a plurality of inward concave induced deformation ribs are arranged on an upper top surface, a lower bottom surface and left and right vertical faces of the tubular structure, four inclined planes of the upper top surface, the lower bottom surface and the vertical faces are planes, larger load can be borne, a more stable and efficient force transmission path is formed under the cooperation of the induced deformation ribs, and a baffle plate is arranged inside the energy-absorbing box, so that the performance similar to that of a multicellular extruded aluminum energy-absorbing box can be provided, and the axial crushing force is effectively improved. The energy-absorbing box is fixed through the horizontal fixed sleeve when being inserted with the longitudinal beam, the integral strength of the joint can be greatly improved, deformation and damage of the end part of the longitudinal beam are prevented, and the maintenance cost after collision is reduced. The invention also provides a corresponding energy-absorbing box manufacturing method, optimizes the process flow, remarkably improves the production efficiency and reduces the material and labor costs.

Inventors

Chuang chao
RUAN SHANGWEN
CHENG PENGZHI
WANG JUNJIE
HE YIJIN
KONG XIANGQIAN

Assignees

航宇智造（北京）工程技术有限公司

Dates

Publication Date: 20260512
Application Date: 20260309

Claims (9)

1. A liquid expansion forming type steel energy-absorbing box structure is characterized in that a tubular structure with a convex octagonal cross section is adopted, and two openings of the tubular structure correspond to an anti-collision cross beam connecting end and a vehicle body longitudinal beam connecting end respectively; the upper top surface, the lower bottom surface and the left vertical elevation of the energy-absorbing box are respectively provided with a plurality of induced deformation ribs which are sunken towards the inside of the energy-absorbing box; at least one sleeve mounting hole is formed in the four inclined planes of the energy-absorbing box at a position close to the connecting end of the longitudinal beam, and the end part of the longitudinal beam is also provided with a corresponding sleeve mounting hole, so that the energy-absorbing box and the longitudinal beam can be inserted and fixed by inserting a fixing sleeve into the sleeve mounting hole and horizontally penetrating the energy-absorbing box and the longitudinal beam in the transverse direction; the energy-absorbing box is internally provided with a baffle plate which is vertically or horizontally arranged and divides the inner cavity of the energy-absorbing box into a left part, a right part, an upper part and a lower part which are corresponding to each other, and a plurality of induced deformation ribs and reinforcing ribs are arranged on the baffle plate in a staggered manner.
2. The structure of claim 1, wherein the energy-absorbing box and the longitudinal beam can be provided with no sleeve mounting hole, and the energy-absorbing box and the longitudinal beam are in butt joint and fixed with the end plate of the longitudinal beam by arranging a mounting plate at the opening of the connecting end of the longitudinal beam of the energy-absorbing box, so that the connecting mode of splicing the energy-absorbing box and the longitudinal beam is replaced.
3. The method of claim 1, wherein the insert-type fixing of the crash box to the side member is achieved by projection welding nuts at the mounting holes of the side members and using bolts instead of fixing the side members.
4. The energy absorber structure of claim 1, wherein the retaining sleeve is secured to the sleeve mounting hole by welding.
5. The structure of claim 1, wherein the spacer is fixed within the energy absorber by spot welding.
6. The method of claim 1, wherein the energy absorber comprises a medium strength steel or stainless steel.
7. The manufacturing method of the liquid expansion forming type steel energy-absorbing box is characterized by comprising the following steps of: step 1, selecting corresponding materials to manufacture pipe blanks according to design dimensions and performance indexes; step 2, placing the pipe blank into a mould to perform liquid expansion forming, so that the pipe blank is expanded and attached to the mould under the pressure of liquid medium filled in the inner cavity of the pipe blank to form a pipe fitting with a convex octagonal section, and a plurality of inward concave induced deformation ribs are formed on the upper top surface, the lower bottom surface and the left vertical elevation of the pipe fitting; step 3, taking out the pipe fitting with the liquid expansion from the die, performing laser cutting to obtain at least one energy-absorbing box single-piece structure and removing waste materials, and performing inclined plane perforating operation on the connecting end of the longitudinal beam of the energy-absorbing box, wherein the inclined plane perforating operation is used as a sleeve mounting hole for inserting and fixing a corresponding fixing sleeve when the connecting end is spliced with the longitudinal beam; Step 4, processing a partition plate, wherein a plurality of induced deformation ribs and reinforcing ribs are formed on the surface of the partition plate in a staggered manner; And 5, vertically or horizontally inserting the partition plate into the inner cavity of the energy-absorbing box, separating the inner cavity into a left part and a right part or an upper part and a lower part, and fixing the partition plate by spot welding to finish manufacturing the energy-absorbing box.
8. The method of claim 7, wherein the ramp tapping operation of step 3 is eliminated and a mounting plate is welded to the beam attachment port of the crash box for butt-securing with the end panel-mounted beam.
9. The method of claim 7, wherein after the sleeve mounting hole is formed by performing the inclined plane opening operation, a nut is fixed at the sleeve mounting hole by projection welding for replacing the fixed sleeve by using a bolt to realize the plug-in fixation of the energy absorption box and the longitudinal beam.

Description

Liquid expansion forming type steel energy-absorbing box structure and manufacturing method thereof Technical Field The invention belongs to the technical field of manufacturing of automobile body structural components, and particularly relates to a liquid expansion molding steel energy-absorbing box structure and a manufacturing method thereof. Background At present, as an important component part in the front collision protection structure of the automobile, the front collision protection structure is mainly manufactured by adopting two modes of steel stamping welding or aluminum extrusion, and various related process links still have some problems, such as the defects of unstable local deformation structure easily caused by the influence of discontinuous connection and arc welding heat when arc welding is carried out on a steel sheet metal part, and the beat of the arc welding process is relatively low. The energy absorption efficiency of the corresponding energy absorption box product is weaker due to the self characteristics of steel, the energy absorption box is generally only used on low-weight and low-cost vehicle types, the performance of the extruded aluminum energy absorption box is greatly improved compared with that of the steel energy absorption box, but the manufacturing cost and the processing difficulty of the extruded aluminum energy absorption box are difficult to reduce at the present stage, the number of working procedures in production is large, and the carbon emission level is extremely high. In the aspect of structural design, compared with the traditional rectangular section structure, the recently-occurring polygonal structure energy-absorbing box has obvious advantages in terms of force transmission efficiency, energy-absorbing efficiency and the like, a certain improvement space still exists, such as the front anti-collision structure patent application CN202511827676.2 of the automobile in front of the applicant, the energy-absorbing box is connected with a longitudinal beam of the automobile through a mounting end plate at the rear part, the problem that the connecting end of the longitudinal beam is more easily influenced by collision and deformed is possibly caused along with the improvement of the energy-absorbing collapse performance of the energy-absorbing box, and if the longitudinal beam is manufactured by adopting a high-strength process and materials, the longitudinal beam cannot be repaired in a sheet metal mode with lower cost after being deformed, and only the whole replacement can be carried out, so that the potential maintenance cost of the automobile is definitely pushed up. Therefore, how to further improve the structure and the manufacturing process of the energy absorption box, and reduce the production and use costs while improving the performance of the energy absorption box is a technical problem which needs to be solved in the field. Disclosure of Invention In view of the above, the invention provides a liquid expansion formed steel energy-absorbing box structure, which adopts a tubular structure with a convex octagon section, and two openings of the tubular structure correspond to an anti-collision cross beam connecting end and a vehicle body longitudinal beam connecting end respectively; the upper top surface, the lower bottom surface and the left vertical elevation of the energy-absorbing box are respectively provided with a plurality of induced deformation ribs which are sunken towards the inside of the energy-absorbing box; at least one sleeve mounting hole is formed in the four inclined planes of the energy-absorbing box at a position close to the connecting end of the longitudinal beam, and the end part of the longitudinal beam is also provided with a corresponding sleeve mounting hole, so that the energy-absorbing box and the longitudinal beam can be inserted and fixed by inserting a fixing sleeve into the sleeve mounting hole and horizontally penetrating the energy-absorbing box and the longitudinal beam in the transverse direction; the energy-absorbing box is internally provided with a baffle plate which is vertically or horizontally arranged and divides the inner cavity of the energy-absorbing box into a left part, a right part, an upper part and a lower part which are corresponding to each other, and a plurality of induced deformation ribs and reinforcing ribs are arranged on the baffle plate in a staggered manner. Furthermore, the sleeve mounting holes can be omitted from the energy absorption boxes and the longitudinal beams, and the mounting plates are arranged at the openings of the connecting ends of the longitudinal beams of the energy absorption boxes and are in butt joint and fixation with the end plates of the longitudinal beams, so that the connecting mode of splicing the energy absorption boxes and the longitudinal beams is replaced. Furthermore, the nut is welded at the sleeve mounting hole through projection welding, and bolts are