A printed circuit board fixing structure

Abstract

A printed circuit board (PCB) fixing structure includes a pair of oppositely arranged side plates. At least one pair of fixing clips are symmetrically fixed to the opposite surfaces of the side plates. Each fixing clip consists of a resilient slot and mounting plates connected to both ends of the resilient slot. The width of the slot opening is smaller than the thickness of the PCB. The mounting plates are fixed to the inner walls of the side plates, and the PCB is inserted into the slot. This invention uses a dovetail-shaped resilient slot, which clamps both sides of the PCB tightly after insertion. During use, there is no elastic collision between the PCB and the slot, improving the reliability of the radio altimeter and extending its service life.

Description

Technical Field

[0001] This utility model belongs to the field of printed circuit board mounting technology, and particularly relates to a printed circuit board fixing structure. Background Technology

[0002] Radio altimeters are crucial instruments for measuring aircraft altitude, and their stability directly impacts flight safety. Existing radio altimeters (such as the Thomson AHV16 from France) contain multiple printed circuit boards (PCBs), which are fixed in place by rigid slots arranged side-by-side on a pair of side panels. After installation, gaps exist between the PCBs and the slots. During use, elastic collisions occur between the PCBs and slots, causing damage, cracking, and desoldering of fragile components on the PCBs (such as ceramic capacitors, crystal oscillators, and connector pins), directly affecting the reliability of the radio altimeter. Utility Model Content

[0003] This invention provides a printed circuit board fixing structure to overcome the shortcomings of the prior art.

[0004] The technical solution adopted by this utility model is: a printed circuit board fixing structure, including a pair of side plates arranged opposite each other, at least a pair of fixing clips symmetrically fixed on the opposite surfaces of the side plates, the fixing clips being composed of elastic slots and mounting plates connected to both ends of the elastic slots, the width of the slot opening of the elastic slot being less than the thickness of the printed circuit board, the mounting plates being fixed on the inner wall of the side plates, and the printed circuit board being inserted into the slot.

[0005] The fixing clip is made of an elastic sheet, with both ends of the elastic sheet serving as the mounting plates. A section of the elastic sheet between the mounting plates is symmetrically bent upwards on both sides to form a dovetail structure, creating an elastic slot. The two ends of the dovetail structure are expanded outwards into V-shaped ports. The printed circuit board is inserted through the V-shaped port, and the printed circuit board is clamped at the slot by the elastic deformation of the two side walls of the dovetail structure.

[0006] The top and both ends of the dovetail structure are provided with outward arc-shaped flanges.

[0007] The elastic sheet is a beryllium bronze strip, the included angle α between the bottom and side surfaces of the dovetail structure is 65±2°, and the width L of the groove is 1.3-1.5mm.

[0008] After the fixing clip is formed, it is first heated to 790±10°C and kept at that temperature for 25 to 30 minutes before being placed in water to cool.

[0009] The mounting plate has rivet holes, and the mounting plate is riveted and fixed to the side plate through the rivet holes.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] 1. This utility model adopts a dovetail-shaped elastic slot. After the printed circuit board is inserted, the two sides of the printed circuit board are clamped by the slot. During use, there will be no elastic collision between the printed circuit board and the slot, which improves the reliability of the radio altimeter and extends its service life.

[0012] 2. The two ends of the dovetail-shaped slot of this utility model are V-shaped ports, which facilitates the smooth insertion of the printed circuit board.

[0013] 3. The edge of the dovetail-shaped slot of this utility model has an outward-flared structure, which avoids the risk of scratching the printed circuit board. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of this utility model;

[0015] Figure 2 This is a schematic diagram of the structure of the fixing clip of this utility model;

[0016] Figure 3 This is a cross-sectional schematic diagram of the fixing clip of this utility model;

[0017] Figure 4 yes Figure 2 Enlarged view of a portion of point A in the middle;

[0018] Figure 5 This is a diagram showing the usage state of this utility model. Detailed Implementation

[0019] The following is in conjunction with the appendix Figure 1-5 The present invention will be described in detail with reference to specific embodiments.

[0020] A printed circuit board fixing structure includes a pair of side plates 5 arranged opposite each other. At least a pair of fixing clips 3 are symmetrically fixed on the opposite surfaces of the side plates 5. The fixing clips 3 are composed of elastic slots 1 and mounting plates 2 connected to both ends of the elastic slots 1. The width of the slot 1-1 of the elastic slot 1 is less than the thickness of the printed circuit board 4 by 1.5 mm. The mounting plates 2 are fixed on the inner wall of the side plates 5. The printed circuit board 4 is inserted into the slot 1-1.

[0021] The fixing clip 3 is made of elastic sheet material. The two ends of the elastic sheet material serve as the mounting plate 2. A section of the elastic sheet material between the mounting plates 2 is symmetrically bent upwards on both sides to form a dovetail structure to form an elastic slot 1. The two ends of the dovetail structure are expanded outwards to form V-shaped ports 1-2. The printed circuit board 4 is inserted from the V-shaped port 1-2. Through the elastic deformation of the two side walls of the dovetail structure, the printed circuit board 4 is clamped at the slot 1-1.

[0022] In the above embodiments, the elastic sheet is preferably a 0.2 mm thick beryllium bronze strip (QBe2-CY), the included angle α between the bottom and side surfaces of the dovetail structure is 65±2°, and the width L of the groove 1-1 is 1.3-1.5 mm. Furthermore, after the fixing clip 3 is formed, it undergoes solution heat treatment, i.e., it is first heated to 790±10°C and held at that temperature for 25-30 minutes before being cooled in water. After heat treatment, the beryllium bronze fixing clip achieves excellent shaping without deformation, while its strength, hardness, and toughness are significantly enhanced.

[0023] Furthermore, the mounting plate 2 is provided with a riveting hole 2-1, and the mounting plate 2 is riveted and fixed to the side plate 5 through the riveting hole 2-1.

[0024] Furthermore, the top and both ends of the dovetail structure are provided with outwardly curved flanges 1-3, which avoids the risk of scratching the printed circuit board.

[0025] For specific application examples, see Figure 5 (Radio Altimeter) First, apply a layer of silicone 3140 to the bottom surface of the mounting plate 2, then rivet it to the side plate 5 through the rivet hole 2-1. After riveting, place it horizontally for 24 hours to allow the silicone 3140 to solidify, thus bonding the fixing clip 3 to the side plate 5. This reduces the risk of breakage at the junction (neck) of the dovetail slot 1 and the mounting plate 2 during use. Then, install the side plate with the fixing clip into the radio altimeter's housing. Finally, insert the printed circuit board 4 from the top of the housing along the V-shaped port into the slot 1-1, clamping both sides of the printed circuit board 4 with the slot 1-1. This overcomes the elastic collision problem caused by gaps in the prior art, reduces the risk of damage, cracking, and desoldering of fragile components (such as ceramic capacitors, crystal oscillators, and connector pins) on the printed circuit board 4, improves the reliability of the radio altimeter, and extends its service life.

[0026] The above embodiments are merely preferred embodiments of the present utility model and are not intended to limit the scope of implementation of the present utility model. Therefore, all equivalent variations made based on the content described in the claims of the present utility model should be included within the scope of the claims of the present utility model.

Claims

1. A printed circuit board fixing structure, characterized in that: The device includes a pair of side plates (5) arranged opposite to each other. At least one pair of fixing clips (3) are symmetrically fixed on the opposite surfaces of the side plates (5). The fixing clips (3) are composed of elastic slots (1) and mounting plates (2) connected to both ends of the elastic slots (1). The width of the slot (1-1) of the elastic slots (1) is smaller than the thickness of the printed circuit board (4). The mounting plates (2) are fixed on the inner wall of the side plates (5). The printed circuit board (4) is inserted into the slot (1-1).

2. The printed circuit board fixing structure according to claim 1, characterized in that: The fixing clip (3) is made of elastic sheet material. The two ends of the elastic sheet material serve as the mounting plate (2). A section of elastic sheet material between the mounting plates (2) is symmetrically bent upwards on both sides to form a dovetail structure to form an elastic slot (1). The two ends of the dovetail structure are expanded outwards to form V-shaped ports (1-2). The printed circuit board (4) is inserted from the V-shaped port (1-2). Through the elastic deformation of the two side walls of the dovetail structure, the printed circuit board (4) is clamped at the slot (1-1).

3. The printed circuit board fixing structure according to claim 2, characterized in that: The top and both ends of the dovetail structure are provided with outward arc-shaped flanges (1-3).

4. A printed circuit board fixing structure according to claim 2 or 3, characterized in that: The elastic sheet is a beryllium bronze strip, the included angle α between the bottom and side surfaces of the dovetail structure is 65±2°, and the width L of the groove (1-1) is 1.3-1.5mm.

5. A printed circuit board fixing structure according to claim 4, characterized in that: After the fixing clip (3) is formed, it is first heated to 790±10° and kept warm for 25 to 30 minutes before being placed in water to cool.

6. The printed circuit board fixing structure according to claim 1, characterized in that: The mounting plate (2) has a riveting hole (2-1), and the mounting plate (2) is riveted to the side plate (5) through the riveting hole (2-1).

Images