Low-profile input coil and metal detector

Abstract

The application discloses a low-space-occupying input coil and a metal detector. The low-space-occupying input coil comprises at least two groups of coil groups, any coil group of the at least two groups of coil groups comprises a first receiving coil, a second receiving coil and a transmitting coil, the first receiving coil, the second receiving coil and the transmitting coil of any coil group are located on a first circuit board of the same layer, and adjacent coil groups of the at least two groups of coil groups are arranged on adjacent first circuit boards. The low-space-occupying input coil can be adapted to a smaller circuit board, so that the metal detector configured with the low-space-occupying input coil can have a longer detection distance and a larger detection range.

Description

Technical Field

[0001] This invention relates to basic electrical devices, and more specifically, to a space-saving input coil and metal detector. Background Technology

[0002] As metal detectors are used in increasingly diverse applications, their input coils require greater detection distance and range. Existing receiving coils are typically designed on the same layer of a circuit board, and the number of turns in the receiving coil is limited, resulting in relatively weak output voltage signal strength and limiting the detection distance and range for metals. Furthermore, to obtain a sufficiently strong output voltage signal, the circuit board area is usually large, which is detrimental to product miniaturization. Summary of the Invention

[0003] One object of the present invention is to provide an input coil and a metal detector with a low footprint.

[0004] According to a first aspect of the present invention, a space-saving input coil is provided, the input coil comprising at least two coil groups, each of the at least two coil groups comprising a first receiving coil, a second receiving coil, and a transmitting coil, wherein the first receiving coil, the second receiving coil, and the transmitting coil of any coil group are all located on a first circuit board on the same layer, and adjacent coil groups of the at least two coil groups are disposed on adjacent first circuit boards.

[0005] Optionally, the first receiving coil of one of the adjacent coil groups is electrically connected to the first receiving coil of another adjacent coil group, and the second receiving coil of one of the adjacent coil groups is electrically connected to the second receiving coil of another adjacent coil group.

[0006] Optionally, the tail end of the first receiving coil of the first coil group in the at least two coil groups is electrically connected to the head end of the first receiving coil of the second coil group in the at least two coil groups, and the tail end of the second receiving coil of the first coil group in the at least two coil groups is electrically connected to the head end of the second receiving coil of the second coil group in the at least two coil groups.

[0007] The tail end of the first receiving coil of the i-th coil group in the at least two coil groups is electrically connected to the head end of the first receiving coil of the (i+1)-th coil group in the at least two coil groups, and the tail end of the second receiving coil of the i-th coil group in the at least two coil groups is electrically connected to the head end of the second receiving coil of the (i+1)-th coil group in the at least two coil groups.

[0008] The tail end of the first receiving coil of the last coil group in the at least two coil groups is electrically connected to the tail end of the second receiving coil of the last coil group in the at least two coil groups; wherein i is an integer and greater than 0.

[0009] Optionally, the winding direction of the first receiving coil of any coil group is the same as the winding direction of the second receiving coil of any coil group.

[0010] Optionally, the first receiving coil of any coil group surrounds the second receiving coil of any coil group, and the second receiving coil of any coil group surrounds the transmitting coil of any coil group.

[0011] Optionally, the projections of any two coil groups in the at least two coil groups on the coil winding axis coincide.

[0012] Optionally, the first end of the first receiving coil of any coil group is located outside the first receiving coil, the tail end of the first receiving coil of any coil group is located inside the first receiving coil, the first end of the second receiving coil of any coil group is located outside the second receiving coil, and the tail end of the second receiving coil of any coil group is located inside the second receiving coil.

[0013] Optionally, the first receiving coil of any coil group has its start and end points located on the target side of the transmitting coil of any coil group, and the second receiving coil of any coil group has its start and end points located on the target side of the transmitting coil of any coil group.

[0014] According to a second aspect of the invention, a metal detector is provided, which includes a space-saving input coil as described in the first aspect.

[0015] Optionally, the metal detector includes multiple layers of first and second circuit boards, with adjacent first circuit boards spaced apart, and the second circuit boards spaced apart on the first side of the last layer of first circuit boards. The second circuit boards are used to house other devices in the metal detector.

[0016] According to one embodiment of this disclosure, the input coil provided in this application can increase the output signal strength of the input coil within the same circuit board area, which is beneficial for improving the detection distance and detection range of the metal under test. Since the output signal strength of the receiving coil is significantly increased, the area of ​​the circuit board can be appropriately reduced, thereby decreasing the product size.

[0017] Other features and advantages of the invention will become clear from the following detailed description of exemplary embodiments of the invention with reference to the accompanying drawings. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the invention and, together with their description, serve to explain the principles of the invention.

[0019] Figure 1 This is a structural block diagram of a low-space-occupancy input coil according to an embodiment of this application.

[0020] Figure 2 This is a schematic diagram of the coil group on the first layer circuit board in an embodiment of this application.

[0021] Figure 3 This is a schematic diagram of the coil group on the second layer circuit board in an embodiment of this application.

[0022] Figure 4 This is a schematic diagram of the coil group on the third layer circuit board in an embodiment of this application.

[0023] Figure 5 This is a layout diagram of the first and second circuit boards of the metal detector according to an embodiment of this application. Detailed Implementation

[0024] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention.

[0025] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0026] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0027] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0028] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0029] This application provides a low-space-occupancy input coil, which includes at least two coil groups. Each of the at least two coil groups includes a first receiving coil, a second receiving coil, and a transmitting coil. The first receiving coil, the second receiving coil, and the transmitting coil of any coil group are all located on a first circuit board on the same layer. Adjacent coil groups in the at least two coil groups are disposed on adjacent first circuit boards.

[0030] In this embodiment, the input coil can be placed on a circuit board of the same area, which can increase the output signal strength of the input coil, thus improving the detection distance and detection range of the metal to be tested. Because the output signal strength of the receiving coil is significantly increased, the area of ​​the circuit board can be appropriately reduced, thereby decreasing the product size.

[0031] In some embodiments, the first receiving coil of one coil group in an adjacent coil group is electrically connected to the first receiving coil of another coil group in an adjacent coil group, and the second receiving coil of one coil group in an adjacent coil group is electrically connected to the second receiving coil of another coil group in an adjacent coil group.

[0032] In this embodiment, as Figure 1 As shown, the input coil may include two coil groups, namely coil group 10A and coil group 10B, which can be adjacent coil groups among at least two coil groups. Coil group 10A may include a first receiving coil 2A, a second receiving coil 3A, and a transmitting coil 1A. Coil group 10B may include a first receiving coil 2B, a second receiving coil 3B, and a transmitting coil 1B. The first receiving coil 2A may be electrically connected to the first receiving coil 2B, the second receiving coil 3A may be electrically connected to the second receiving coil 3B, and the transmitting coil 1A may be electrically connected to the transmitting coil 1B. Furthermore, coil group 10A and coil group 10B are respectively disposed on different first circuit boards, and the two first circuit boards are adjacent to each other.

[0033] In this embodiment, electrically connecting the first receiving coil in the two coil groups and electrically connecting the second receiving coil in the two coil groups can effectively improve the output signal strength of the input coil, and further improve the detection distance and detection range of the metal to be tested.

[0034] In some embodiments, the tail end of the first receiving coil of the first coil group in at least two coil groups is electrically connected to the head end of the first receiving coil of the second coil group in at least two coil groups, and the tail end of the second receiving coil of the first coil group in at least two coil groups is electrically connected to the head end of the second receiving coil of the second coil group in at least two coil groups.

[0035] The tail end of the first receiving coil of the i-th coil group in at least two coil groups is electrically connected to the head end of the first receiving coil of the (i+1)-th coil group in at least two coil groups, and the tail end of the second receiving coil of the i-th coil group in at least two coil groups is electrically connected to the head end of the second receiving coil of the (i+1)-th coil group in at least two coil groups.

[0036] The tail end of the first receiving coil of the last coil group in at least two coil groups is electrically connected to the tail end of the second receiving coil of the last coil group in at least two coil groups; where i is an integer and greater than 0.

[0037] In this embodiment, as Figures 2 to 4 As shown, at least two sets of coils can be used, or there can be three sets of coils. Figure 2 The coil group in the first coil group is the first coil group among at least two coil groups. The first receiving coil of the first coil group is the first receiving coil 2A, the first end of the first receiving coil 2A is the A1 end, and the last end of the first receiving coil 2A is the B1 end. The second receiving coil of the first coil group is the second receiving coil 3A, the first end of the second receiving coil 3A is the C1 end, and the last end of the second receiving coil 3A is the D1 end. The transmitting coil of the first coil group is the transmitting coil 1A. Figure 3 The coil group in the second coil group is the second coil group among at least two coil groups. The first receiving coil of the second coil group is the first receiving coil 2B, the first end of the first receiving coil 2B is the A2 end, and the last end of the first receiving coil 2A is the B2 end. The second receiving coil of the second coil group is the second receiving coil 3B, the first end of the second receiving coil 3B is the C2 end, and the last end of the second receiving coil 3B is the D2 end. The transmitting coil of the second coil group is the transmitting coil 1B. Figure 3The coil group in the last of at least two coil groups is the first receiving coil 2C, with its first end at A3 and its last end at B3. The second receiving coil is the second receiving coil 3C, with its first end at C3 and its last end at D3. The transmitting coil in the last coil group is the transmitting coil 1C. The B1 end of the first receiving coil 2A can be electrically connected to the A2 end of the first receiving coil 2B, and the B2 end of the first receiving coil 2B can be electrically connected to the A3 end of the first receiving coil 2C. This allows the first receiving coils 2A, 2B, and 2C to be connected end-to-end with consistent winding directions. The D1 terminal of the second receiving coil 3A is electrically connected to the C2 terminal of the second receiving coil 3B, and the D2 terminal of the second receiving coil 3B is electrically connected to the C3 terminal of the second receiving coil 3C. This allows the second receiving coils 3A, 3B, and 3C to be connected end-to-end with consistent winding directions. The B3 terminal of the first receiving coil 2C is electrically connected to the D3 terminal of the second receiving coil 3C, ensuring that the winding directions of the first and second receiving coils are exactly opposite.

[0038] In this embodiment, by setting multiple sets of coil groups, the output signal strength of the input coil can be effectively improved, thereby increasing the detection distance and detection range of the metal to be tested.

[0039] In some embodiments, the winding direction of the first receiving coil of any coil group is the same as the winding direction of the second receiving coil of any coil group.

[0040] In this embodiment, as Figure 2 As shown, the first receiving coil of any coil group can be the first receiving coil 2A, and the second receiving coil of any coil group can be the second receiving coil 3A. The winding direction of both the first receiving coil 2A and the second receiving coil 3A can be clockwise. By setting the winding direction of the first receiving coil and the second receiving coil to be the same, it is convenient for the operator to combine multiple coil groups.

[0041] In some embodiments, a first receiving coil of any coil group surrounds a second receiving coil of any coil group, and a second receiving coil of any coil group surrounds a transmitting coil of any coil group.

[0042] In this embodiment, as Figure 2As shown, the first receiving coil of any coil group can be a first receiving coil 2A, the second receiving coil of any coil group can be a second receiving coil 3A, and the transmitting coil of any coil group can be a transmitting coil 1A. The first receiving coil 2A surrounds the second receiving coil 3A, and the second receiving coil 3A surrounds the transmitting coil 1A. By setting a unified arrangement of the first receiving coil, the second receiving coil, and the transmitting coil, it is easier for operators to combine multiple coil groups.

[0043] In some embodiments, the projections of any two coil groups in at least two coil groups on the coil winding axis coincide.

[0044] In this embodiment, as Figure 2 As shown, the winding axis of the coil can be the axis of the transmitting coil 1A. By setting the projections of any two coil groups onto the winding axis to coincide, the output signal strength of the input coil can be effectively improved, thereby increasing the detection distance and detection range of the metal to be tested.

[0045] In some embodiments, the beginning of the first receiving coil of any coil group is located outside the first receiving coil, the end of the first receiving coil of any coil group is located inside the first receiving coil, the beginning of the second receiving coil of any coil group is located outside the second receiving coil, and the end of the second receiving coil of any coil group is located inside the second receiving coil.

[0046] In this embodiment, as Figure 2 As shown, the first receiving coil of any coil group can be the first receiving coil 2A, and the second receiving coil of any coil group can be the second receiving coil 3A. The first receiving coil 2A has its starting end A1, meaning its A1 end is located on the outside of the first receiving coil 2A. The last end of the first receiving coil 2A is B1, meaning its A1 end is located on the inside of the first receiving coil 2A. The second receiving coil 3A has its starting end C1, and its last end D1, meaning its C1 end is located on the outside of the second receiving coil 3A. The last end of the second receiving coil 3A is D1, meaning its D1 end is located on the inside of the second receiving coil 3A. By setting the endpoints of the first and second receiving coils to fixed positions, it is easier for operators to combine multiple coil groups.

[0047] In some embodiments, the beginning and end of the first receiving coil of any coil group are both located on the target side of the transmitting coil of any coil group, and the beginning and end of the second receiving coil of any coil group are both located on the target side of the transmitting coil of any coil group.

[0048] In this embodiment, as Figure 2As shown, the first receiving coil of any coil group can be a first receiving coil 2A, and the second receiving coil of any coil group can be a second receiving coil 3A. The first receiving coil 2A has end A1 and end B1. The second receiving coil 3A has end C1 and end D1. Ends A1 and B1 of the first receiving coil 2A are both on the left side of the transmitting coil 1A, and ends C1 and D1 of the second receiving coil 3A are both on the left side of the transmitting coil 1A. By setting the endpoints of the first and second receiving coils to be on the same side, it is easier for operators to combine multiple coil groups.

[0049] This application also provides a metal detector that includes a space-saving input coil of any of the above embodiments.

[0050] In some embodiments, the metal detector includes multiple layers of first circuit boards and second circuit boards, with adjacent first circuit boards spaced apart and second circuit boards spaced apart on the first side of the last layer of first circuit boards. The second circuit boards are used to house other devices in the metal detector.

[0051] In this embodiment, since the thickness of the circuit board is mostly less than 1.6mm, the distance between the coil groups of any two layers of the circuit board is very close. Furthermore, the induced voltage generated by the first receiving coil of each layer's coil group is approximately the same, and the induced voltage generated by the second receiving coil of each layer's coil group is also approximately the same. By using a multilayer board and setting up coil groups, a signal superposition effect can be achieved. Taking a four-layer board as an example... Figure 5 As shown, the multi-layer first circuit board may include a first circuit board 4A, a first circuit board 4B, and a first circuit board 4C. The first coil group can be disposed on the first circuit board 4A, the second coil group can be disposed on the first circuit board 4B, and the last coil group can be disposed on the first circuit board 4C. The second circuit board may be a second circuit board 5. This allows the coil group to have three layers, and the final signal strength is approximately three times that of a double-sided board (with only one layer of coil group), achieving a longer detection distance and a larger detection range under the same conditions. Simultaneously, this multi-layer coil group and circuit board work together, allowing for more flexible application in products and enabling a reduction in circuit board size while maintaining the same signal strength, thus facilitating product miniaturization.

[0052] While specific embodiments of the invention have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of the invention. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. A low footprint input coil, characterized by, The input coil comprises at least two groups of coil groups, any coil group of the at least two groups of coil groups comprises a first receiving coil, a second receiving coil and a transmitting coil, the first receiving coil, the second receiving coil and the transmitting coil of the any coil group are located on the same layer of the first circuit board, adjacent coil groups of the at least two groups of coil groups are arranged on adjacent first circuit boards; The first receiving coil of one coil group of the adjacent coil groups is electrically connected with the first receiving coil of another coil group of the adjacent coil groups, and the second receiving coil of one coil group of the adjacent coil groups is electrically connected with the second receiving coil of another coil group of the adjacent coil groups; The leading end of the first receiving coil of the any coil group is located on the outside of the first receiving coil, the trailing end of the first receiving coil of the any coil group is located on the inside of the first receiving coil, the leading end of the second receiving coil of the any coil group is located on the outside of the second receiving coil, and the trailing end of the second receiving coil of the any coil group is located on the inside of the second receiving coil; The winding direction of the first receiving coil of the any coil group is the same as the winding direction of the second receiving coil of the any coil group; The first receiving coil of the any coil group is wrapped around the second receiving coil of the any coil group, and the second receiving coil of the any coil group is wrapped around the transmitting coil of the any coil group; The projection of any two coil groups of the at least two groups of coil groups in the coil winding axis direction coincides.

2. The low-profile input coil of claim 1, wherein, The trailing end of the first receiving coil of the first coil group of the at least two groups of coil groups is electrically connected with the leading end of the first receiving coil of the second coil group of the at least two groups of coil groups, and the trailing end of the second receiving coil of the first coil group of the at least two groups of coil groups is electrically connected with the leading end of the second receiving coil of the second coil group of the at least two groups of coil groups; The trailing end of the first receiving coil of the i-th coil group of the at least two groups of coil groups is electrically connected with the leading end of the first receiving coil of the i+1-th coil group of the at least two groups of coil groups, and the trailing end of the second receiving coil of the i-th coil group of the at least two groups of coil groups is electrically connected with the leading end of the second receiving coil of the i+1-th coil group of the at least two groups of coil groups; The trailing end of the first receiving coil of the last coil group of the at least two groups of coil groups and the trailing end of the second receiving coil of the last coil group of the at least two groups of coil groups are electrically connected; wherein i is an integer greater than 0.

3. The low-profile input coil of claim 1, wherein, The leading end and the trailing end of the first receiving coil of the any coil group are located on the target side of the transmitting coil of the any coil group, and the leading end and the trailing end of the second receiving coil of the any coil group are located on the target side of the transmitting coil of the any coil group.

4. A metal detector characterized by, The metal detector comprises the low-space-occupancy input coil according to any one of claims 1 to 3.

5. The metal detector of claim 4, wherein, The metal detector comprises a plurality of first circuit boards and a second circuit board, the adjacent first circuit boards are arranged at intervals, and the second circuit board is arranged at the first side of the last first circuit board at intervals, and the second circuit board is used for arranging other devices in the metal detector.

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