Halow antenna device applied to POS machine

Abstract

The utility model relates to a halo antenna device applied to a POS machine, which comprises a flexible circuit board, a coaxial cable, a connector and a main board which are connected in sequence, a gap is arranged on the flexible circuit board, and a place contact point on the gap is connected with a feed point contact point. Compared with the prior art, the flexible printed circuit board is provided with the gap, so that the performance peak value and the waveform bandwidth are balanced, and the influence of poor assembly consistency caused by difference of disassembly and assembly machines and mounting errors can be resisted to a certain extent; the ground contact point and the feed point contact point on the flexible circuit board are connected, so that the anti-interference capability is stronger; the flexible circuit board is mounted by adopting the plastic bracket far away from a metal part, so that the antenna performance is improved; the cable is wound along the plastic bracket, so that the interference of a battery of the POS machine is avoided to a certain extent; and the flexible circuit board is connected with the metal plate on the back surface of the screen through the conductive cloth, so that the waveform stability and the anti-interference capability of the antenna are greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of communication antennas, in particular to a halow antenna device applied to a POS machine. Background Art

[0002] With the rapid development of the communications industry, the communication functions of various IoT products have increased, and the number of internal antennas required for IoT products has also increased. However, for various IoT products, product performance and appearance are always the top priority, which leads to the stacking of internal components taking precedence over the antenna environment. When it is difficult to make major adjustments to the internal environment of the product, how to reasonably use the internal environment of the product to maximize the performance and stability of the antenna has become a challenge we must face.

[0003] At present, the antenna performance is generally improved by increasing the antenna radiation area and using unconventional grounding methods, while increasing the antenna's anti-interference ability, but this also requires the form of the antenna and the connection method with the motherboard. Especially for existing products such as POS machines, which have a long overall shape and a long screen, and have other low-frequency antennas and various cables inside, many internal devices will generate low-frequency co-frequency clutter, which can easily affect the performance of the halow antenna.

[0004] Therefore, how to design a halow antenna device with strong anti-interference performance and suitable for POS machines is a technical problem that needs to be solved. Utility Model Content

[0005] The purpose of the utility model is to provide a halow antenna device applied to a POS machine in order to overcome the defect of poor halow antenna performance of the POS machine in the prior art.

[0006] The purpose of the utility model can be achieved through the following technical solutions:

[0007] According to one aspect of the utility model, a halow antenna device applied to a POS machine is provided, comprising a flexible circuit board, a coaxial cable, a connector and a main board connected in sequence, wherein the flexible circuit board is provided with a gap, a ground contact point and a feed contact point, and the ground contact point and the feed contact point are connected.

[0008] As a preferred technical solution, the device also includes a plastic bracket, which is in the shape of an elongated strip and is installed on a side close to the POS screen and perpendicular to the POS screen. The flexible circuit board is installed on the plastic bracket, and the coaxial cable is wound along the plastic bracket.

[0009] As a preferred technical solution, the plastic bracket is the same length as the side close to the POS machine screen.

[0010] As a preferred technical solution, the distance between the position where the coaxial cable is connected to the flexible circuit board and one end of the plastic bracket is 20 mm.

[0011] As a preferred technical solution, the ground contact point and the feed contact point on the flexible circuit board are respectively located on both sides of the gap.

[0012] As a preferred technical solution, the flexible circuit board includes a flexible circuit board body and an ink layer, the ink layer wraps the flexible circuit board body and has an area larger than the flexible circuit board, and one of the two corners of the ink layer close to one side of the screen is not provided with a flexible circuit board.

[0013] As a preferred technical solution, the flexible circuit board is connected to the metal plate on the back of the POS machine screen through a conductive cloth.

[0014] As a preferred technical solution, the connector is connected to the mainboard via a microstrip line.

[0015] As a preferred technical solution, the length of the coaxial cable connecting the flexible circuit board and the connector is 200 mm.

[0016] As a preferred technical solution, the dimensions of the flexible circuit board are 65 mm in length and 15 mm in width.

[0017] Compared with the prior art, the utility model has the following beneficial effects:

[0018] 1) The utility model provides a slot in the flexible circuit board, which effectively improves the performance of the antenna. The length of the slot balances the performance peak and the waveform bandwidth, and can resist the influence of poor assembly consistency caused by differences in disassembly and assembly machines and mounting errors to a certain extent; and the ground contact point and the feed contact point on the flexible circuit board are connected, so the anti-interference ability is stronger; the slot is connected to the ground feed to achieve the anti-interference ability when operating in the 870MHz to 930MHz frequency band, and the performance is better;

[0019] 2) The utility model uses a plastic bracket to install the flexible circuit board, away from metal parts, which is conducive to improving antenna performance;

[0020] 3) The plastic bracket of the utility model is installed on the side close to the POS machine screen and perpendicular to the POS machine screen. The cable is wound along the plastic bracket to avoid interference from the POS machine battery to a certain extent. One of the two corners of the ink layer close to the screen side is not provided with a flexible circuit board, so that the more sensitive end of the antenna can avoid interference from the screen below.

[0021] 4) The flexible circuit board of the utility model is connected to the metal plate on the back of the screen through a conductive cloth, which greatly improves the waveform stability and anti-interference ability of the antenna, greatly reduces the impact of the low-frequency bands of other antennas and the low-frequency clutter generated by the various cables inside the product on the performance of the antenna, and effectively reduces the occurrence of antenna frequency deviation caused by slight differences in the placement of the coaxial cable during the assembly process. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the structure of a halow antenna device used in a POS machine according to the utility model;

[0023] Figure 2 This is the return loss diagram of the utility model;

[0024] The numbers in the figure show:

[0025] 1. Flexible circuit board, 10. Flexible circuit board body, 11. Ink layer, 101. Gap, 102. Location contact point, 103. Feed point contact point, 2. Coaxial cable, 3. Connector. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of them. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0027] like Figure 1 As shown, the utility model provides a halow antenna device applied to a POS machine, comprising a flexible circuit board 1, a coaxial cable 2, a connector 3 and a plastic bracket. The working frequency of the antenna device is 870M-930M Hz, and the working temperature is -30 to 70 degrees Celsius.

[0028] The flexible circuit board 1 is connected to the metal plate on the back of the POS machine screen through a conductive cloth. The flexible circuit board 1 includes a flexible circuit board body 10 and an ink layer 11. The ink layer 11 wraps the flexible circuit board body 10 and has an area larger than the flexible circuit board 1. The ink layer 11 is attached to the side of the plastic bracket. One of the two corners of the ink layer 11 close to the screen side is not provided with the flexible circuit board 1. The size of the flexible circuit board 1 is 65 mm long and 15 mm wide. A slit 101 is provided on the flexible circuit board body 10, and a ground contact point 102 and a feed contact point 103 are provided. The ground contact point 102 and the feed contact point 103 are located on both sides of the slit 101. The slit 101 is centered on the position where the ground contact point 102 and the feed contact point 103 are located, and extends to both sides of the flexible circuit board 1. The method of extending from the center to both sides facilitates the control of the length of the slit 101. The ground contact point 102 and the feed contact point 103 are connected. The opening of the slit 101 on the flexible circuit board 1 will affect the relationship between the performance peak and bandwidth of the antenna. If the slit 101 is too long, the bandwidth will be too wide and the peak value will be insufficient. If the slit 101 is too short, the peak value will be very high but the bandwidth will be insufficient. The efficiency values ​​at different frequencies are shown in Table 1:

[0029] Table 1 Frequency and efficiency comparison values

[0030] Frequency(MHz) Efficiency(dB) 860 -6.64 870 -5.43 880 -4.76 890 -4.57 900 -4.54 910 -4.57 920 -5.04 930 -5.64 940 -6.32 950 -6.98

[0031] The coaxial cable 2 connects the flexible circuit board 1 and the connector 3. The structure of the coaxial cable 2 from the inside to the outside is: core wire, dielectric layer, braided layer and protective layer. The braided layer and the core wire are connected to each other through the flexible circuit board 1. The length of the coaxial cable 2 is 200mm, and the length of the coaxial cable 2 from the flexible circuit board 1 to one end of the plastic bracket (i.e., the corner of the POS machine) is 20mm.

[0032] Connector 3 is connected to the main board via a microstrip line.

[0033] The plastic bracket is in the shape of a long strip, installed on a side close to the POS screen and perpendicular to the POS screen, and has the same length as the screen on this side. The flexible circuit board 1 is installed on the plastic bracket, and the coaxial cable 2 is wound along the plastic bracket.

[0034] like Figure 2 The figure shows the return loss of different frequencies when the utility model is working. The horizontal axis in the figure is frequency (unit: MHz), and the vertical axis is the return loss depth (unit: dB). Under normal circumstances, the antenna efficiency is higher at the frequency point where the return loss is deeper. For example, the frequency of point 1 in the figure is 870MHz, the depth is -6dB, and the frequency of point 2 is 930MHz, and the depth is also -6dB. It can be seen that the waveform of the antenna has not deviated.

[0035] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the utility model, and these modifications or replacements should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A halow antenna device applied to a POS machine, characterized in that: The invention comprises a flexible circuit board (1), a coaxial cable (2), a connector (3) and a main board which are connected in sequence. The flexible circuit board (1) is provided with a slit (101), a ground contact point (102) and a feed contact point (103). The ground contact point (102) and the feed contact point (103) are connected.

2. A halow antenna device for POS terminal according to claim 1, characterized in that: The device also comprises a plastic bracket, which is in the shape of a long strip and is installed on a side close to and perpendicular to the POS machine screen. The flexible circuit board (1) is installed on the plastic bracket, and the coaxial cable (2) is wound along the plastic bracket.

3. A halow antenna device for POS terminal according to claim 2, characterized in that: The plastic bracket has the same length as the side close to the POS machine screen.

4. The halow antenna device used in a POS terminal according to claim 3, characterized in that: The distance between the position where the coaxial cable (2) is connected to the flexible circuit board (1) and one end of the plastic bracket is 20 mm.

5. The halow antenna device used in a POS machine according to claim 1, characterized in that: The ground contact point (102) and the feed contact point (103) on the flexible circuit board (1) are respectively located on two sides of the gap (101).

6. The halow antenna device used in a POS terminal according to claim 1, characterized in that: The flexible circuit board (1) comprises a flexible circuit board body (10) and an ink layer (11), wherein the ink layer (11) wraps the flexible circuit board body (10) and has an area larger than the flexible circuit board (1), and the flexible circuit board (1) is not arranged at one of the two corners of the ink layer (11) close to one side of the screen.

7. The halow antenna device used in a POS terminal according to claim 1, characterized in that: The flexible circuit board (1) is connected to the metal plate on the back of the POS machine screen via a conductive cloth.

8. The halow antenna device used in a POS machine according to claim 1, characterized in that: The connector (3) is connected to the mainboard via a microstrip line.

9. The halow antenna device used in a POS terminal according to claim 1, characterized in that: The length of the coaxial cable (2) connecting the flexible circuit board (1) and the connector (3) is 200 mm.

10. The halow antenna device used in a POS machine according to claim 1, characterized in that: The dimensions of the flexible circuit board (1) are 65 mm in length and 15 mm in width.

Images