Aviation stud press-fitting method

Abstract

The invention provides an aviation stud press-fitting method, and belongs to the technical field of machinery. According to the aviation stud press-fitting method, a pre-pressing mold is included, the pre-pressing mold comprises an upper mold assembly, a lower mold assembly and a pressing assembly, the upper mold assembly comprises an upper driving part with an upper extrusion face, and a containing hole is formed in the center of the upper extrusion face; the lower die assembly comprises a floating part, an execution part and a lower driving part; the floating part is elastically connected with the lower driving part through an elastic piece to form an axial floating space; the floating component is provided with a sliding hole, and the execution component is fixedly connected to the lower driving component and penetrates through the sliding hole of the floating component to form a sliding pair. In the initial state, a compressible gap is reserved between the floating component and the lower driving component.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of machinery, in particular to an aviation stud press-fitting method. BACKGROUND

[0002] The stud is a common hardware in the aviation and electrical system, which is usually assembled with the product by press riveting to bear the function of fixed connection. The press-fitting process is as follows: first, the product is positioned and placed, then the stud is loaded into the product preset hole, and then the whole is placed into the lower die to carry out press riveting operation. The traditional press-fitting process is easily affected by stress, which leads to the deviation of the product surface flatness, and the stud end surface is higher than the sheet metal surface. If the press-fitting pressure is increased to improve the adhesion, the deformation problem of the thin plate product as shown in the accompanying drawings will be caused. Some products have strict requirements on the press riveting quality, which stipulates that the stud end surface should be lower than the product surface by 0-0.25mm, and the product should not be deformed obviously. For the thin-walled, multi-stud press-fitting and high-priced product, the unqualified single press riveting will cause significant quality loss. Figure 6 SUMMARY

[0003] The purpose of the present application is to solve the above-mentioned problems existing in the prior art, and to provide an aviation stud press-fitting method.

[0004] The purpose of the present application can be realized by the following technical scheme:

[0005] An aviation stud press-fitting method, comprising a pre-pressing die, the pre-pressing die comprising:

[0006] an upper die assembly comprising an upper driving part with an upper extrusion surface, the upper extrusion surface being provided with a receiving hole at the center;

[0007] a lower die assembly comprising a floating part, an executing part and a lower driving part; the floating part is elastically connected with the lower driving part through an elastic member to form an axial floating space; the floating part is provided with a sliding hole, and the executing part is fixedly connected with the lower driving part and penetrates through the sliding hole of the floating part to form a sliding pair; wherein, in the initial state, a compressible gap is reserved between the floating part and the lower driving part;

[0008] The method comprises the following steps:

[0009] S1, positioning the stud into the sliding hole of the lower die assembly, and providing axial support by the executing part;

[0010] S2, sleeving the corresponding hole of the aluminum plate on the outer edge of the stud;

[0011] S3, pressing the upper die assembly and the lower die assembly to make the aluminum plate in pre-pressing contact with the upper extrusion surface of the upper die assembly and the floating part, and the upper end of the stud enters the receiving hole for positioning; the pre-pressing force is in the range of 600-700 PSI; ​

[0012] S4, the driving execution component continues to go up, and the stud is pressed into the aluminum plate to a target depth, so that the end surface of the stud is lower than the surface of the product by not more than 0.25 mm.

[0013] In the aviation stud press-fitting method, the floating component has a pre-pressing surface arranged in parallel with the lower surface of the upper die, so that the pressure is uniformly distributed.

[0014] In the aviation stud press-fitting method, the lower driving component is provided with at least two guide columns, the floating component has a guide hole, the guide column is in sliding fit with the guide hole of the floating component, the guide columns are symmetrically arranged on both sides of the execution component, and a limiting part is arranged at the end of the guide column; the limiting part is used to constrain the floating stroke.

[0015] In the aviation stud press-fitting method, the end of the guide column has a bolt part, the bolt part is threadedly connected with the lower driving component, and the guide column is used to control the maximum floating stroke of the floating component.

[0016] In the aviation stud press-fitting method, a counterbore is arranged around the guide hole, and the limiting part is arranged in the counterbore.

[0017] In the aviation stud press-fitting method, in the initial state, the execution component is retracted into the sliding hole, so that the sliding hole and the execution component form a containing cavity, and the end of the stud can enter the containing cavity.

[0018] In the aviation stud press-fitting method, the execution component can be adjusted to protrude from the sliding hole port by 0-0.25 mm.

[0019] In the aviation stud press-fitting method, the thickness of the aluminum plate is greater than 1 mm.

[0020] In the aviation stud press-fitting method, the elastic member is one of a spring and an elastic gasket.

[0021] Compared with the prior art, the application has the following advantages:

[0022] In the present application, the upper extrusion surface of the upper driving component is in contact with the upper surface of the aluminum plate, and the upper end of the stud enters the accommodation hole in the center of the upper extrusion surface, realizing the radial secondary positioning of the stud; the upper die continuously descends to apply a pre-pressure of 600-700 PSI, pushing the floating component to compress the elastic element and slide axially along the execution component until the reserved gap is eliminated. During this process, the pre-pressure makes the aluminum plate fully adhere to the floating component and the upper extrusion surface, which corrects the relative positional deviation of the aluminum plate and the stud on the one hand, and releases the residual stress of the aluminum plate itself on the other hand, avoiding deformation caused by stress concentration in the subsequent press-fitting process. The execution component continuously ascends along the sliding pair in a rigid pushing manner to press the stud into the to-be-pressed hole of the aluminum plate; since the pre-pressing stage has realized the accurate positioning of the aluminum plate and the stud, the pre-pressure has uniformized the stress distribution of the plate material, reducing the subsequent press-fitting reaction force, and the stud can be smoothly pressed along the preset axis until the stud end surface is below the target depth of 0-0.25mm of the aluminum plate surface, completing the press-fitting operation. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is the structure diagram of the pre-pressing die in the present application on the aluminum plate;

[0024] Figure 2 is the exploded schematic diagram of the pre-pressing die in the present application;

[0025] Figure 3 is the flow step schematic diagram in step S1 in the present application;

[0026] Figure 4 is the flow step schematic diagram in step S2 in the present application;

[0027] Figure 5 is the pre-pressing step flow schematic diagram in step S3 in the present application;

[0028] Figure 6 is the flow step schematic diagram in step S4 in the present application;

[0029] Figure 7 is the schematic diagram of embodiment 1 and embodiment 2 in the present application;

[0030] Figure 8 is the schematic diagram of embodiment 3, embodiment 4 and embodiment 5 in the present application;

[0031] In the figure,

[0032] 100, stud; 200, aluminum plate;

[0033] 2. Pre-compression mold; 21. Upper mold assembly; 211. Upper extrusion surface; 212. Accommodating hole; 22. Lower mold assembly; 221. Floating component; 2211. Sliding hole; 22111. Accommodating cavity; 2212. Pre-compression surface; 2213. Guide hole; 2214. Countersunk hole; 222. Actuating component; 223. Lower drive component; 2231. Guide post; 22311. Bolt part; 2232. Limiting part; 224. Elastic element; 225. Compression gap. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0035] like Figures 1 to 6 As shown, a method for press-fitting an aircraft stud 100 includes a pre-pressing mold 2, which comprises an upper mold assembly 21 and a lower mold assembly 22. The upper mold assembly 21 includes an upper drive component with an upper extrusion surface 211, the upper extrusion surface 211 having a receiving hole 212 at its center. The lower mold assembly 22 includes a floating component 221, an actuating component 222, and a lower drive component 223. The floating component 221 is elastically connected to the lower drive component 223 via an elastic element 224 to form an axial floating space. The floating component 221 has a sliding hole 2211, and the actuating component 222 is fixed to the lower drive component 223 and passes through the sliding hole 2211 of the floating component 221 to form a sliding pair. In the initial state, a compressible gap 225 is reserved between the floating component 221 and the lower drive component 223.

[0036] The method includes the following steps:

[0037] S1. Position the stud 100 into the sliding hole 2211 of the lower mold assembly 22, with axial support provided by the actuating component 222;

[0038] S2. Fit the corresponding hole of the aluminum plate 200 onto the outer edge of the stud 100;

[0039] S3, the upper mold assembly 21 and the lower mold assembly 22 are pressed together, so that the aluminum plate 200 is in pre-pressed contact with the upper extrusion surface 211 of the upper mold assembly 21 and the floating component 221. At the same time, the upper end of the stud 100 enters the receiving hole 212 for positioning. The pre-pressure range is 600-700 PSI. The pre-pressure will gradually increase when the floating component 221 and the actuating component 222 are compressed.

[0040] S4, the driving execution component 222 continues to go up, and the stud 100 is pressed into the aluminum plate 200 to the target depth, ensuring that the end surface of the stud 100 is not more than 0.25mm below the surface of the product.

[0041] In this application, the upper extrusion surface 211 of the upper driving component is in contact with the upper surface of the aluminum plate 200, and the upper end of the stud 100 enters the accommodation hole 212 in the center of the upper extrusion surface 211, realizing the radial secondary positioning of the stud 100; the upper die continues to go down to apply a pre-pressure of 600-700PSI, pushing the floating component 221 to compress the elastic element 224 and slide along the axis of the execution component 222 until the reserved gap is eliminated. During this process, the pre-pressure makes the aluminum plate 200 fully adhere to the floating component 221 and the upper extrusion surface 211, which on the one hand corrects the relative position deviation of the aluminum plate 200 and the stud 100, and on the other hand releases the residual stress of the aluminum plate 200 itself through uniform pre-pressing, avoiding deformation caused by stress concentration in the subsequent press-fitting process. The driving execution component 222 continues to go up along the sliding pair to press the stud 100 into the hole to be pressed in the aluminum plate 200 in a rigid pushing manner; because the accurate positioning of the aluminum plate 200 and the stud 100 has been realized in the pre-pressing stage, the stud 100 can be smoothly pressed along the preset axis until the end surface of the stud 100 is 0-0.25mm below the surface of the aluminum plate 200, and the press-fitting work is completed.

[0042] Specifically, the floating component 221 has a pre-pressing surface 2212, which is arranged parallel to the lower pressing surface of the upper die, so that the pressure is uniformly distributed.

[0043] The pre-pressing surface 2212 of the floating component 221 is arranged parallel to the lower pressing surface of the upper die, so that the pressure applied by the mold is uniformly conducted along the contact surface of the aluminum plate 200, and the aluminum plate 200 can always maintain a horizontal posture during the pre-pressing process, ensuring that the hole to be pressed in the aluminum plate 200 is accurately aligned with the axis of the stud 100, avoiding the problem of stud 100 press-fitting deviation caused by the inclination of the aluminum plate 200,

[0044] Specifically, the lower driving component 223 is equipped with at least two guide columns 2231, and the floating component 221 has guide holes 2213, and the guide columns 2231 and the guide holes 2213 of the floating component 221 are in sliding fit; the guide columns 2231 are symmetrically distributed on both sides of the execution component 222, and the end of the guide column 2231 is provided with a limiting portion 2232; the limiting portion 2232 is used to constrain the floating stroke.

[0045] The guide posts 2231 symmetrically distributed on both sides of the execution component 222 and the floating component 221 guide hole 2213 form a sliding fit, providing precise guide constraint for the axial floating of the floating component 221, avoiding the radial deviation or tilt of the floating component 221 during pre-pressing and press-fitting, ensuring that the stud 100 is always pressed into the aluminum plate 200 along the preset axis, further improving the control accuracy of the stud 100 end face depth tolerance.

[0046] At the same time, this design makes the pressure transmission path stable and controllable during the pre-pressing stage, ensuring that the pre-pressing force is accurately applied to the aluminum plate 200 at a maximum stroke of 600-700 PSI, avoiding excessive extrusion of other pressure marks on the surface of the aluminum plate 200.

[0047] Specifically, the end of the guide post 2231 has a bolt part 22311, and the bolt part 22311 is threadedly connected with the lower driving component 223, wherein the guide post 2231 is used to control the maximum floating stroke of the floating component 221.

[0048] The guide post 2231 is threadedly connected with the lower driving component 223 through the end bolt part 22311, and the depth of the guide post 2231 screwed into the lower driving component 223 can be adjusted by rotating the guide post 2231, thereby accurately changing the maximum floating stroke of the floating component 221. At the same time, different elastic members 224 with different elastic strengths can be replaced. This design can adapt to different press-fitting process requirements without the need to replace the entire mold component, greatly improving the versatility and process adjustment efficiency of the mold.

[0049] Specifically, a counterbore 2214 is arranged around the guide hole 2213, and the limiting part 2232 is arranged in the counterbore 2214.

[0050] The embedded design of the counterbore 2214 can completely accommodate the limiting part 2232 of the guide post 2231, avoiding interference between the limiting part 2232 and the aluminum plate 200 and the upper mold assembly 21.

[0051] Specifically, in the initial state, the execution component 222 is retracted into the sliding hole 2211, so that the sliding hole 2211 and the execution component 222 form a containing cavity 22111, and the end of the stud 100 can enter the containing cavity 22111.

[0052] In the initial state, the execution component 222 is retracted into the sliding hole 2211 to form a containing cavity 22111, and the end of the stud 100 can be directly embedded in the containing cavity 22111. The inner wall of the containing cavity 22111 and the outer wall of the stud 100 form a radial limiting constraint, ensuring that the axis of the stud 100 is accurately aligned with the axis of the sliding hole 2211 and the upper mold containing hole 212, thereby avoiding the problem of deviation and tilting of the stud 100 during press-fitting from the source.

[0053] Specifically, the execution component 222 can adjust the extension of the sliding hole 2211 port 0-0.25mm.

[0054] The execution component 222 can adjust the extension of the sliding hole 2211 port 0-0.25mm, and the adjustment stroke fully corresponds to the technical requirement that the end surface of the stud 100 needs to be 0-0.25mm lower than the surface of the product. By accurately setting the extension amount of the execution component 222, the final depth of the stud 100 pressed into the aluminum plate 200 can be directly controlled, the quantitative regulation of the pressing depth is realized, and the product core size tolerance is guaranteed to meet the standard from the structural design level.

[0055] Specifically, the thickness of the aluminum plate 200 is greater than 1mm.

[0056] Specifically, the elastic member 224 is one of a spring and an elastic gasket.

[0057] As shown in Figure 7 and Figure 8 Embodiment 1 and Embodiment 2 are the cases of the stud 100 pressed into the aluminum plate 200 without pre-pressing, and Embodiment 3, Embodiment 4 and Embodiment 5 are the cases of the stud 100 pressed into the aluminum plate 200 through the pre-pressing mold 2.

[0058] Embodiment 1 is Figure 1 the left side pressing trace in FIG. 1, Embodiment 2 is Figure 1 the right side pressing trace in FIG. 1, Embodiment 3 is Figure 2 the uppermost side pressing trace in FIG. 1, Embodiment 4 is Figure 2 the middle pressing trace in FIG. 1, and Embodiment 5 is Figure 2 the lowermost side pressing trace in FIG. 1.

[0059] Pre-pressing pressure PSI Whether the deformation pressing depth / mm

[0060]

[0061] According to the table, it can be obviously seen that after pre-pressing by the pre-pressing mold 2, the stress at the position of the stud 100 can be effectively eliminated, so that the deformation at the position can be avoided.

[0062] It should be noted that all directional indications in the embodiments of the present application, such as up, down, left, right, front, back, etc., are only used to explain the relative position relationship, movement condition, etc. between components in a certain specific posture, as shown in the drawings, and if the specific posture changes, the directional indications also change accordingly.

[0063] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Meanwhile, the word "and / or" throughout the text means including three solutions; for example, "A and / or B" includes solution A, solution B, or a solution that simultaneously satisfies A and B. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0064] All of the above components are general standard parts or components known to those skilled in the art. Their structure and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0065] The specific embodiments described herein are merely illustrative examples of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the invention or exceeding the scope defined by the appended claims.

Claims

1. A method for press-fitting aircraft studs, characterized in that, Includes a pre-compression mold (2), said pre-compression mold (2) comprising: The upper die assembly (21) includes an upper drive component having an upper extrusion surface (211) and a receiving hole (212) at the center of the upper extrusion surface (211). The lower mold assembly (22) includes a floating component (221), an actuating component (222), and a lower drive component (223). The floating component (221) is elastically connected to the lower drive component (223) through an elastic element (224) to form an axial floating space. The floating component (221) has a sliding hole (2211). The actuating component (222) is fixed to the lower drive component (223) and passes through the sliding hole (2211) of the floating component (221) to form a sliding pair. In the initial state, a compressible gap (225) is reserved between the floating component (221) and the lower drive component (223). The method includes the following steps: S1. Position the stud (100) into the sliding hole (2211) of the lower mold assembly (22), with axial support provided by the actuating component (222); S2. Fit the corresponding hole of the aluminum plate (200) onto the outer edge of the stud (100); S3, the upper mold assembly (21) and the lower mold assembly (22) are pressed together, so that the aluminum plate (200) is in pre-pressed contact with the upper extrusion surface (211) of the upper mold assembly (21) and the floating part (221), and at the same time, the upper end of the stud (100) enters the receiving hole (212) for positioning. The pre-pressure range is 600-700 PSI. S4. Drive the actuator (222) to continue moving upward, pressing the stud (100) into the aluminum plate (200) to the target depth, ensuring that the end face of the stud (100) is no more than 0.25mm below the product surface.

2. The aircraft stud press-fitting method according to claim 1, characterized in that, The floating component (221) has a pre-pressing surface (2212), which is arranged parallel to the lower pressing surface of the upper mold to ensure uniform pressure distribution.

3. The aircraft stud press-fitting method according to claim 1, characterized in that, The lower drive component (223) is equipped with at least two guide posts (2231), and the floating component (221) has a guide hole (2213). The guide posts (2231) are slidably engaged with the guide hole (2213) of the floating component (221). The guide posts (2231) are symmetrically distributed on both sides of the actuator (222), and the ends of the guide posts (2231) are provided with limiting parts (2232). The limiting parts (2232) are used to constrain the floating stroke.

4. The aircraft stud press-fitting method according to claim 3, characterized in that, The end of the guide post (2231) has a bolt portion (22311), which is threadedly connected to the lower drive component (223), wherein the guide post (2231) is used to control the maximum floating stroke of the floating component (221).

5. The aircraft stud press-fitting method according to claim 1, characterized in that, A countersunk hole (2214) is provided around the guide hole (2213), and the limiting part (2232) is provided inside the countersunk hole (2214).

6. The aircraft stud press-fitting method according to claim 1, characterized in that, In the initial state, the actuating component (222) is retracted into the sliding hole (2211) so that the sliding hole (2211) and the actuating component (222) form a receiving cavity (22111) and the end of the stud (100) can enter the receiving cavity (22111).

7. The aircraft stud press-fitting method according to claim 1, characterized in that, The actuator (222) can be adjusted to extend 0-0.25mm from the port of the sliding hole (2211).

8. The method for press-fitting aircraft studs according to claim 1, characterized in that, The thickness of the aluminum plate (200) is greater than 1 mm.

9. The method for press-fitting aircraft studs according to claim 1, characterized in that, The elastic element (224) is one of a spring or an elastic washer.

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