Lightweight sheet metal rack and forming method thereof

Abstract

The invention provides a light-weight sheet metal rack and a forming method thereof. The sheet metal rack comprises a surrounding frame side plate, a transition part, a supporting plate, a reinforcing aluminum plate and a pressing rivet nut. The integral riveting tool is adopted, the riveting sequence is optimized, high-precision forming of the metal plate rack is achieved, and the key precision of the rack can be within + / -0.1 mm. Compared with a similar machining part assembling and forming mode, the cost is reduced by more than 90% (12,000 yuan), and the weight is reduced by more than 50% (6.1 Kg).

Description

Technical Field

[0001] This invention relates to the field of sheet metal design and forming technology, and in particular to a lightweight sheet metal frame and its forming method. Background Technology

[0002] As the mounting carrier for complex electronic equipment components, the precision of the rack directly determines the stability and reliability of the component's electrical performance, thus affecting the overall antenna performance. Due to the high precision requirements for rack forming, racks have traditionally been assembled from machined parts, resulting in heavy and costly machined racks. With the development of complex electronic equipment towards higher mobility and intensified industry competition, higher demands are being placed on lightweight and low-cost component manufacturing.

[0003] To achieve lightweight design and reduce production costs, the industry typically uses low-cost forming methods such as sheet metal. However, for medium and large-sized complex sheet metal frame parts, the riveting accuracy is usually at the millimeter level, which does not meet the high-precision assembly requirements of complex electronic equipment components.

[0004] Therefore, there is an urgent need to invent a lightweight design and low-cost, high-precision sheet metal forming method to meet the demand for low-cost and lightweight development of complex electronic equipment. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies, this invention proposes a lightweight sheet metal frame and its forming method; this invention is achieved through the following scheme:

[0006] A lightweight sheet metal frame includes side panels, transition pieces, support plates, reinforcing aluminum plates, and rivet nuts. The side panels include a front panel, a rear panel, a left panel, and a right panel, all formed by bending aluminum plates. The transition pieces are aluminum profiles used to rivet the side panels together. The support plates are installed on the inner sides of the left and right panels, and are equipped with reference holes and rivet nuts to ensure assembly accuracy. The reinforcing aluminum plates are riveted to the four outer corners of the left and right panels to enhance the overall structural strength.

[0007] Preferably, the aluminum plate has a thickness of 3mm and an accuracy of ±0.1mm.

[0008] Preferably, the spacing accuracy between the reference hole of the support plate and the left and right plates is ±0.2mm; the accuracy between the positioning holes of the left plate is ±0.1mm; the accuracy between the positioning holes of the left and right plates is ±0.1mm; the accuracy between the positioning holes of the two support plates is ±0.3mm; and the accuracy between the positioning holes of the left plate 2 and the support plate 3 is ±0.2mm.

[0009] This invention also proposes a method for forming a lightweight sheet metal frame, comprising the following steps:

[0010] (1) Assemble the front side panel and two transition pieces using a single-piece tooling to form component 1, and assemble the rear side panel and two transition pieces using a single-piece tooling to form component 2;

[0011] (2) Using riveting fixtures, install 4 reinforcing plates at the four corners of the left side plate and 4 reinforcing plates at the four corners of the right side plate, and then preassemble the left side plate, right side plate, component 1 and component 2.

[0012] (3) Use riveting fixtures for positioning to rivet the left side plate to the support plate and the right side plate to the support plate;

[0013] (4) Use riveting fixtures for positioning, and use a drilling template to drill reference holes for the support plate. The hole position accuracy is ±0.1mm.

[0014] (5) Install a press-fit nut on the support plate 3. The accuracy of the press-fit nut hole is ±0.2mm.

[0015] Preferably, after step (5), the method further includes removing the sheet metal frame from the riveting fixture, measuring the dimensional accuracy of the sheet metal frame, and ensuring that the spacing accuracy between the reference hole of the support plate and the left and right plates is ±0.2mm; the accuracy between the positioning holes of the left plate is ±0.1mm; the accuracy between the positioning holes of the left and right plates is ±0.1mm; the accuracy between the positioning holes of the two support plates is ±0.3mm; and the accuracy between the positioning holes of the left plate 2 and the support plate 3 is ±0.2mm.

[0016] Compared with the prior art, the significant advantages of this invention are:

[0017] The lightweight sheet metal frame of this invention is formed by riveting together a large number of sheet metal and profile parts, which is lighter and less expensive than the assembly of traditional machined parts.

[0018] The lightweight sheet metal frame of this invention achieves high forming accuracy through riveting fixtures and high-precision forming process technology.

[0019] A lightweight, low-cost frame was designed. By employing an integral riveting fixture and optimizing the riveting sequence, high-precision forming of the sheet metal frame is achieved, with key frame accuracy reaching within ±0.1mm. Compared to similar machined parts assembly methods, the cost is reduced by more than 90% (12,000 yuan), and the weight is reduced by more than 50% (6.1 kg). Attached Figure Description

[0020] Figure 1 Axonometric view of a lightweight sheet metal frame;

[0021] Figure 2 Top view of a lightweight sheet metal frame;

[0022] Figure 3 Side sectional view of a lightweight sheet metal frame;

[0023] Figure 4 This is a schematic diagram of the installation of a single-piece riveting fixture;

[0024] Figure 5 This is a schematic diagram of the frame and riveting fixture installation;

[0025] Figure 6 Flowchart of the frame riveting sequence;

[0026] Figure 7 A schematic diagram showing the stress distribution of a lightweight sheet metal frame under vertical vibration.

[0027] Figure 8 This is a schematic diagram showing the stress distribution of a lightweight sheet metal frame under lateral impact. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings.

[0029] Combination Figures 1-3 This invention discloses a lightweight sheet metal frame, comprising side panels, transition pieces, support plates, reinforcing aluminum plates, and rivet nuts. The side panels include a front panel 1, a rear panel 6, a left panel 2, and a right panel 8, all formed by bending 3mm thick aluminum plates with a forming accuracy controlled within ±0.1mm. The transition piece 5 is an aluminum profile used to rivet the four side panels together. The support plates 3 are respectively installed on the inner sides of the left panel 2 and the right panel 8, and the support plates 3 are provided with reference holes and rivet nuts 4 to ensure assembly accuracy. The reinforcing aluminum plates 7 are respectively riveted to the four corners of the outer side of the left panel 2 and the four corners of the outer side of the right panel 8 to strengthen the overall structural strength.

[0030] Combination Figures 1-3 The lightweight sheet metal frame of the present invention has the following forming accuracy control: the spacing accuracy between the reference hole of the support plate 3 and the left side plate 2 and the right side plate 8 is A±0.2mm; the accuracy between the positioning holes of the left side plate 2 is B±0.1mm; the accuracy between the positioning holes of the left side plate 2 and the right side plate 8 is C±0.1mm; the accuracy between the positioning holes of the two support plates 3 is D±0.3mm; and the accuracy between the positioning holes of the left side plate 2 and the support plate 3 is E±0.2mm.

[0031] Combination Figures 7-8The lightweight sheet metal frame of this invention was simulated under impact and random vibration dynamics. The specific simulation results are as follows: Under vertical random vibration, the maximum stress of the frame is 121.7 MPa; the impact condition is set as a sawtooth wave impact acceleration of 12g and a pulse duration of 11 ms. Transient impact analysis was performed on the frame in three directions. Under transverse vertical impact, the maximum stress of the frame is 122.3 MPa. The maximum stresses under both impact and random vibration are lower than the yield strength of 145 MPa, meeting the usage requirements.

[0032] Combination Figures 1-6 The lightweight sheet metal frame forming method of the present invention is as follows:

[0033] (1) The front panel 1 and two transition pieces 5 are assembled into component 1 using single-piece tooling, and the rear panel 6 and two transition pieces 5 are assembled into component 2 using single-piece tooling.

[0034] Riveting fixtures are used to ensure the outer edge spacing accuracy is ±0.1mm, and TOX riveting machines are used to rivet, effectively ensuring riveting quality and efficiency;

[0035] (2) Use riveting fixtures to pre-assemble the left side plate 2, right side plate 8, and 8 aluminum plates 7 with the above-formed components 1 and 2. In the natural state, use a feeler gauge to check that the gap between the lower surface of the side plate and the fixture is less than 0.05mm. Padded and pressed firmly to reduce stress deformation caused by clamping.

[0036] Use a riveting gun for trial riveting to confirm the riveting quality. If necessary, adjust the riveting distance of the riveting gun to complete the riveting process.

[0037] (3) Using riveting fixtures for positioning, the left side plate 2 is riveted to the support plate 3 and the right side plate 8 is riveted to the support plate 3 to form a shape;

[0038] (4) The positioning is achieved by using riveting fixtures and drilling templates to drill the reference holes of the support plate 3. The accuracy of the hole position is measured to be within ±0.1mm.

[0039] (5) Install the rivet nut 4 on the support plate 3, and re-measure the rivet nut hole to ensure that the accuracy is within ±0.2mm;

[0040] (6) Remove the frame from the riveting fixture, re-measure the dimensional accuracy, and confirm that A±0.2mm, B±0.1mm, C±0.1mm, D±0.3mm, and E±0.2mm.

[0041] Example 1:

[0042] The rack of a complex electronic equipment assembly component adopts this design scheme, which reduces the cost of a single rack by more than 90% (12,000 yuan), the cumulative cost reduction by 1.2 million yuan, the weight of a single component by 50% (6.1 kg), the cumulative weight reduction by 610 kg, and the molding accuracy can reach ±0.1 mm, ensuring the stability and reliability of the component's electrical performance.

[0043] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications, additions, or similar substitutions to the described specific embodiments without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A lightweight sheet metal frame, characterized in that, The system includes a frame side panel, a transition piece (5), a support plate (3), a reinforcing aluminum plate (7), and a rivet nut (4). The frame side panel includes a front side panel (1), a rear side panel (6), a left side panel (2), and a right side panel (8), all of which are formed by bending aluminum plates. The transition piece (5) is an aluminum profile, which is used to rivet the frame side panels together. The support plate (3) is installed on the inner side of the left side panel (2) and the right side panel (8), respectively. The support plate (3) is provided with a reference hole and a rivet nut (4) to ensure assembly accuracy. The reinforcing aluminum plate (7) is riveted to the four corners of the outer side of the left side panel (2) and the four corners of the outer side of the right side panel (8) to strengthen the overall structural strength.

2. The lightweight sheet metal frame according to claim 1, characterized in that, The aluminum plate is 3mm thick with a precision of ±0.1mm.

3. The lightweight sheet metal frame according to claim 1, characterized in that, The spacing accuracy between the reference hole of the support plate (3) and the left plate (2) and the right plate (8) is ±0.2mm; the accuracy between the positioning holes of the left plate (2) is ±0.1mm; the accuracy between the positioning holes of the left plate (2) and the right plate (8) is ±0.1mm; the accuracy between the positioning holes of the two support plates (3) is ±0.3mm; and the accuracy between the positioning holes of the left plate 2 and the support plate 3 is ±0.2mm.

4. A method for forming a lightweight sheet metal frame as described in any one of claims 1-3, characterized in that, Includes the following steps: (1) Assemble the front side panel (1) and two transition pieces (5) using a single piece of tooling to form component 1, and assemble the rear side panel (6) and two transition pieces (5) using a single piece of tooling to form component 2; (2) Using riveting fixtures, install 4 reinforcing plates (7) at the four corners of the left side plate (2) and 4 reinforcing plates (7) at the four corners of the right side plate (8), and then pre-assemble the left side plate (2), right side plate (8), component 1 and component 2. (3) Using a riveting fixture for positioning, the left side plate (2) is riveted to the support plate (3), and the right side plate (8) is riveted to the support plate (3) to form a shape; (4) Use riveting fixtures for positioning, and use a drilling template as a support plate (3) to drill reference holes with a hole position accuracy of ±0.1mm; (5) Install the rivet nut (4) on the support plate 3. The accuracy of the rivet nut hole is ±0.2mm.

5. The method for forming a lightweight sheet metal frame according to claim 4, characterized in that, After step (5), the sheet metal frame is removed from the riveting fixture, and the dimensional accuracy of the sheet metal frame is measured to ensure that the spacing accuracy between the reference hole of the support plate (3) and the left side plate (2) and the right side plate (8) is ±0.2mm; the accuracy between the positioning holes of the left side plate (2) is ±0.1mm; the accuracy between the positioning holes of the left side plate (2) and the right side plate (8) is ±0.1mm; the accuracy between the positioning holes of the two support plates (3) is ±0.3mm; and the accuracy between the positioning holes of the left side plate 2 and the support plate 3 is ±0.2mm.

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