Resonant sheet and preparation method thereof, and acoustic magnetic label

Abstract

The invention relates to a resonator, a preparation method thereof and an acoustic magnetic label, and belongs to the technical field of acoustic magnetism. According to the invention, by adjusting the proportion of each component of the resonator and reducing the content of Co and Ni, the amorphous ribbon for preparing the resonator can be subjected to heat treatment at a lower temperature (such as 200-309 DEG C), the heat treatment efficiency is high, the required time is only 3-15 seconds, the resonator with good alarm performance and better consistency can be obtained, and an unexpected technical effect is achieved. The resonator provided by the invention is used for the acoustic magnetic tag, can reduce the fluctuation of the alarm performance of the acoustic magnetic tag, and is suitable for mass production of the acoustic magnetic tag with stable performance.

Description

Technical Field

[0001] The present invention relates to the field of acoustic and magnetic technology, and in particular to a resonance sheet and a preparation method thereof, and an acoustic and magnetic label. Background Art

[0002] As one of the electronic commodity systems, the acoustic magnetic system is widely used for its superior performance. The specific working principle of the acoustic magnetic system is: the transmitting antenna transmits an alternating magnetic field. When the acoustic magnetic tag enters the alternating magnetic field (detection area), and the acoustic magnetic tag resonant frequency is consistent with the carrier frequency in the alternating magnetic field, due to the magneto-elastic resonance effect, the resonance plate in the acoustic magnetic tag will generate a resonance signal under the action of the magnetic field provided by the bias plate and be received by the receiving antenna, thereby detecting the presence of the acoustic magnetic tag. The acoustic magnetic system generally consists of two parts: one is a detector including a transmitting antenna and a receiving antenna, which uses the transmitting antenna to emit an alternating magnetic field to form a detection sensing area between the transmitting antenna and the receiving antenna, and uses the magneto-elastic resonance principle to search for valid tags within a specific range. When a valid tag appears, an alarm is triggered; the other is an acoustic magnetic tag, which is mainly composed of a resonance plate that generates magneto-mechanical resonance and a bias plate that provides a bias magnetic field. The resonance plate is accurately cut from an amorphous metal strip into a size with a resonant frequency of 57.5-58.5kHz through the action of the bias magnetic field provided by the bias plate, which can generate magneto-mechanical resonance in the detection area and reflect to the receiving antenna.

[0003] Disposable acoustic magnetic labels are an indispensable protective product for open-shelf sales in the retail industry. The global annual consumption is in the order of tens of billions of pieces. Developing acoustic magnetic labels with stable alarm performance has always been the unremitting goal pursued by technical personnel in this industry in order to ensure merchants' loss prevention requirements, reduce the defective rate of labels and reduce the cost of qualified products.

[0004] At present, the resonance plates of acoustic magnetic tags need to be sheared after the quenched amorphous ribbon is subjected to a continuous heat treatment furnace with tension control or transverse magnetic field to produce induced anisotropy, so as to make resonance plates with excellent resonance performance. Since the quenched amorphous (before heat treatment) is a highly unstable structure, the performance of its amorphous ribbon (such as the resonance frequency at a specific length and a specific bias field) is very sensitive to changes in heat treatment. Heat treatment at a higher temperature will make the process of structural relaxation difficult to control, resulting in a higher dispersion of the final performance. However, too low a temperature will make the heat treatment time too long and the efficiency will be reduced. Since the invention of the acoustic magnetic tag in 1982, the conventional thinking has been that the lowest heat treatment temperature of the amorphous ribbon used in its resonance plate cannot be lower than 310°C. It is generally believed that good alarm performance can only be achieved after heat treatment at a temperature range of 310-380°C. For example, U.S. Patent No. 5,786,872 also discloses the methods currently known to technicians in this industry and the temperatures of each temperature zone of heat treatment of 320-400°C. The existing technology currently uses a temperature of 300-420°C to heat treat an amorphous ribbon. For example, U.S. Patent No. 6011475 discloses a heat treatment method for an amorphous ribbon at 300-420°C (including temperature, magnetic field strength and direction, etc., which are currently known to technicians in the industry); U.S. Patent No. 5676767 discloses a continuous heat treatment furnace with a treatment temperature of 310-350°C; however, the amorphous ribbons disclosed in the above prior arts all have a higher content of cobalt and / or a higher content of nickel. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a resonance sheet and a preparation method thereof, and an acoustic magnetic label.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] In a first aspect, the present invention provides a resonance plate, comprising the following components by weight percentage: 0-31% nickel, 0-15% cobalt, 1-12% molybdenum, 0-8% other transition metals, 1-16% boron, 0-6% silicon, 0-1% phosphorus, 0-2% aluminum, 0-2% carbon, and iron as the remainder, wherein the other transition metals are transition metals other than iron, nickel, cobalt, and molybdenum.

[0008] The present invention adjusts the composition ratio of the resonance plate and reduces the content of Co and Ni, so that the amorphous ribbon used to prepare the resonance plate can be heat-treated at a relatively low temperature (such as 200-309°C), and the heat treatment efficiency is high, and the time required is only 3-15s, so that a resonance plate with good alarm performance and good consistency can be obtained, achieving unexpected technical effects.

[0009] As a preferred embodiment of the present invention, the width of the resonance piece is 2 to 7 mm.

[0010] In a second aspect, the present invention provides a method for preparing the resonance sheet as described in the first aspect, comprising the following steps:

[0011] S1, preparing a quenched amorphous ribbon;

[0012] S2. heat-treating the quenched amorphous ribbon at a temperature of 195-309° C. to obtain a resonance plate.

[0013] As a preferred embodiment of the present invention, the temperature of the heat treatment is 220 to 306°C, more preferably 260 to 305°C, and even more preferably 269 to 300°C.

[0014] As a preferred embodiment of the present invention, the heat treatment time is 3 to 15 seconds.

[0015] In a third aspect, the present invention provides an acousto-magnetic tag, comprising a shell, a biasing member and a resonance plate as described in the second aspect; the resonance plate is arranged in the inner cavity of the shell, and the biasing member is arranged on the outer side or the inner side of the shell.

[0016] As a preferred embodiment of the present invention, the biasing member is in sheet or wire shape.

[0017] As a preferred embodiment of the present invention, the resonance frequency of the acoustomagnetic tag is 57.5-58.5 kHz.

[0018] As a preferred embodiment of the present invention, the number of resonance sheets contained in the acousto-magnetic tag is 1 to 7 sheets.

[0019] As a preferred embodiment of the present invention, the total weight of the resonance sheet contained in the acousto-magnetic tag is 0.05-0.12 g.

[0020] The resonance sheet provided by the present invention is used for an acousto-magnetic tag, which can reduce the volatility of the alarm performance of the acousto-magnetic tag and is suitable for mass production of acousto-magnetic tags with stable alarm performance.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention adjusts the composition ratio of the resonance plate and reduces the content of Co and Ni, so that the amorphous ribbon used to prepare the resonance plate can be heat-treated at a relatively low temperature (such as 200-309°C), and the heat treatment efficiency is high, and the time required is only 3-15 seconds, so that a resonance plate with good alarm performance and good consistency can be obtained, achieving unexpected technical effects.

[0023] The resonance sheet provided by the present invention is used for an acousto-magnetic tag, which can reduce the volatility of the alarm performance of the acousto-magnetic tag and is suitable for mass production of acousto-magnetic tags with stable alarm performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the structure of the acousto-magnetic tag provided by the present invention.

[0025] In the figure, 1-resonance plate, 2-shell, 3-inner cavity, 4-biasing member. DETAILED DESCRIPTION

[0026] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0027] In a first aspect, the present invention provides a resonance plate, which is made of an alloy material and includes the following components in weight percentage: 0-31% nickel, 0-15% cobalt, 1-12% molybdenum, 0-8% other transition metals, 1-16% boron, 0-6% silicon, 0-1% phosphorus, 0-2% aluminum, 0-2% carbon, and iron as the remainder, wherein the other transition metals are transition metals other than iron, nickel, cobalt, and molybdenum.

[0028] For example, in the resonance sheet, the weight percentage of nickel can be 0, 5%, 10%, 15%, 20%, 25%, 30%, 31% or a range consisting of any two of the values; the weight percentage of cobalt can be 0, 3%, 5%, 6%, 10%, 12%, 15% or a range consisting of any two of the values; the weight percentage of molybdenum can be 1%, 3%, 5%, 6%, 8%, 10%, 12% or a range consisting of any two of the values; the weight percentage of other transition metals can be 0, 2%, 4%, 6%, 8% or a range consisting of any two of the values; the weight percentage of boron can be 1%, 3%, 5%, 7%, 10%, 12%, 14%, 16% or a range consisting of any two of the values. The weight percentage of silicon can be 0, 1%, 2%, 3%, 4%, 5%, 6% or a range consisting of any two of the values; the weight percentage of phosphorus can be 0, 0.3%, 0.5%, 0.7%, 0.8%, 1% or a range consisting of any two of the values; the weight percentage of aluminum can be 0, 0.3%, 0.5%, 0.7%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2% or a range consisting of any two of the values; the weight percentage of carbon can be 0, 0.3%, 0.5%, 0.7%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2% or a range consisting of any two of the values. If the weight percentage of a metal is 0, it means that the resonance plate does not contain the metal.

[0029] The present invention adjusts the composition ratio of the resonance plate and reduces the content of Co and Ni, so that the amorphous ribbon used to prepare the resonance plate can be heat-treated at a relatively low temperature (such as 200-309°C), and the heat treatment efficiency is high, and the time required is only 3-15s, so that a resonance plate with good alarm performance and good consistency can be obtained, achieving unexpected technical effects.

[0030] In one embodiment, the other transition metal includes at least one of Cr, Mn, Cu, Ti, V, Zr, Nb, and W.

[0031] In one embodiment, the width of the resonance plate is 2-7 mm, for example, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm or a range consisting of any two values ​​therein.

[0032] In a second aspect, the present invention provides a method for preparing the resonance sheet as described in the first aspect, comprising the following steps:

[0033] S1, preparing a quenched amorphous ribbon;

[0034] S2, heat-treating the quenched amorphous ribbon to obtain a resonance plate.

[0035] In one embodiment, step S1 prepares the raw materials of the quenched amorphous ribbon according to the weight percentage of each component of the resonance plate described in the first aspect, mixes and melts the raw materials, and prepares the quenched amorphous ribbon of the required width by melt rapid quenching, or cuts the quenched amorphous ribbon of the required width after the melt rapid quenching preparation. The raw materials of the quenched amorphous ribbon can be a single substance or an alloy.

[0036] In one embodiment, the heat treatment temperature is 200-309°C, for example, it can be 200°C, 210°C, 220°C, 230°C, 240°C, 250°C, 260°C, 269°C, 270°C, 280°C, 290°C, 300°C, 305°C, 306°C, 309°C or a range consisting of any two of the values.

[0037] Specifically, the temperature of the heat treatment is preferably 220 to 306°C, more preferably 260 to 305°C, and even more preferably 269 to 300°C.

[0038] In one embodiment, the heat treatment time is 3 to 15 seconds, for example, it can be 3 seconds, 4 seconds, 5 seconds, 6 seconds, 7 seconds, 8 seconds, 9 seconds, 10 seconds, 11 seconds, 12 seconds, 13 seconds, 14 seconds, 15 seconds or a range consisting of any two values ​​therein.

[0039] In one embodiment, the magnetic field intensity of the heat treatment is 0 to 2000 Gs, for example, it can be 0 Gs, 500 Gs, 1000 Gs, 1200 Gs, 1500 Gs, 1800 Gs, 2000 Gs or a range consisting of any two values ​​therein.

[0040] In the third aspect, the present invention provides an acousto-magnetic tag, comprising a shell 2, a biasing member 4 and a resonance piece 1 as described in the second aspect; the resonance piece 1 is arranged in the inner cavity of the shell 2, and the biasing member 4 is arranged on the outer side or the inner side of the shell 2.

[0041] In one embodiment, the biasing member 4 is in the form of a sheet or a wire.

[0042] In one embodiment, the resonance frequency of the acoustomagnetic tag is 57.5-58.5 kHz.

[0043] In one embodiment, the number of resonant sheets contained in the acoustomagnetic tag is 1 to 7 sheets, for example, it can be 1 sheet, 2 sheets, 3 sheets, 4 sheets, 5 sheets, 6 sheets, or 7 sheets.

[0044] In one embodiment, the total weight of the resonance sheet contained in the acoustomagnetic tag is 0.05-0.11 g.

[0045] The present invention tests the frequency fluctuation of the acoustic magnetic label relative to the center frequency. The testing method is as follows: 100 acoustic magnetic labels are cut open, and resonance sheets are taken out and poured out. The resonance sheets contained in each acoustic magnetic label are taken as a set. When testing each set of resonance sheets, the whole set of resonance sheets is placed in a measuring coil, a DC magnetic field is applied, and the magnetic field strength is adjusted within the range of 3 to 8 Oe so that the resonance frequency of each set of resonance sheets is within the range of 57.7 to 58.3 kHz. The specific resonance frequency of each set of resonance sheets is recorded, and the number of sets of resonance sheets with the largest number of same-frequency resonances is counted and screened out, and the resonance frequency is taken as the center frequency; the number of sets of resonance sheets within the range of center frequency -0.1 kHz to center frequency +0.1 kHz (i.e., a stable frequency interval) is counted (represented as n), and the percentage of the number of sets of resonance sheets with stable resonance frequencies within this interval to the total number of tested resonance sheets N is calculated according to the following formula: percentage (%) = n / N*100%, (N = 100). The test results show that if the composition and heat treatment process parameters of the resonance plate are within the specified range of the present invention, the percentage is not less than 30%, for example, it can be not less than any of the following values ​​or between any two of the following values: 30%, 35%, 40%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%.

[0046] This shows that the resonance sheet provided by the present invention is used for the acoustomagnetic tag. While reducing the cobalt and nickel content of the resonance sheet, the frequency fluctuation of the resonance sheet in the acoustomagnetic tag is reduced, the consistency of the acoustomagnetic tag is improved, and the fluctuation of the alarm performance of the acoustomagnetic tag is reduced. The acoustomagnetic tag is suitable for mass assembly and production of acoustomagnetic tags with stable alarm performance.

[0047] After creative efforts (such as adjusting the chemical composition of the resonance sheet, reducing or even eliminating cobalt and nickel), the inventors found that when the heat treatment temperature of the resonance sheet of the present invention is further reduced to 200-309°C, it is not impossible to use it for qualified acousto-magnetic tags as the conventional technology believed in the past. On the contrary, the resonance sheet of the present invention can make the resonance frequency of the acousto-magnetic tag more stable and have good anti-theft alarm performance.

[0048] The present invention provides the following examples to facilitate understanding of the present invention. The present invention provides these examples but is not intended to limit the scope of the claims.

[0049] Example 1

[0050] The embodiment of the resonance sheet and the acoustomagnetic label of the present invention, the resonance sheet is made of alloy material, and the composition of the resonance sheet is shown in Table 1; the acoustomagnetic label includes a shell 2, a biasing member 4, and the resonance sheet 1 provided in this embodiment; the resonance sheet 1 is arranged in the inner cavity 3 of the shell 2, and the biasing member 4 is arranged on the outer side of the shell 2. The number of resonance sheets contained in the acoustomagnetic label and the width of the resonance sheets are shown in Table 2.

[0051] The preparation method of the resonance sheet is as follows:

[0052] S1. According to the weight percentage of each component of the resonance plate described in the first aspect, raw materials for quenched amorphous ribbon are prepared, the raw materials are mixed and smelted, and a quenched amorphous ribbon of a desired width is prepared by melt rapid quenching method, or a quenched amorphous ribbon of a desired width is obtained by cutting after melt rapid quenching preparation;

[0053] S2. The quenched amorphous ribbon is passed through the three temperature zones of the heat treatment furnace at a uniform speed. The process parameters of the heat treatment (temperatures of the three temperature zones, time required to pass through the three temperature zones and magnetic field strength of the equipment) are shown in Table 2 to obtain the resonance sheet.

[0054] Examples 2 to 13 and Comparative Example 1

[0055] The only difference between Examples 2 to 13 and Comparative Example 1 and Example 1 is that the composition of the resonance plates in Examples 2 to 13 and Comparative Example 1 is as shown in Table 1, and the process parameters of the heat treatment, the number and width of the resonance plates contained in the acoustomagnetic tag are as shown in Table 2.

[0056] Performance Testing:

[0057] According to the structures of the acoustic magnetic labels of the above-mentioned embodiments and comparative examples, batch assembly production is carried out. For each embodiment, 100 acoustic magnetic labels are taken for testing. After the acoustic magnetic labels are cut open, the resonance sheets are taken out and poured out. During the test, the resonance sheets contained in each acoustic magnetic label are regarded as a set. The test results are shown in Table 3. The test method is:

[0058] (1) Use a balance to weigh the total weight of each set of resonance plates;

[0059] (2) Place the whole set of resonance plates in the measuring coil, apply a DC magnetic field, adjust the magnetic field strength in the range of 3 to 8 Oe so that the resonance frequency of each set of resonance plates is within the range of 57.7 to 58.3 kHz, and record the specific resonance frequency of each set of resonance plates. Count and select the largest number of sets of resonance plates that resonate at the same frequency, and take this resonance frequency as the center frequency; count the number of sets of resonance plates in the range of -0.1 kHz to +0.1 kHz (i.e., the stable frequency range in Table 3) (denoted as n), and calculate the percentage of the number of sets of resonance plates with stable resonance frequencies in this range to the total number of tested resonance plates N (referred to as the percentage of the stable frequency range) according to the following formula: Percentage (%) = n / N*100%, (N = 100).

[0060] Table 1

[0061]

[0062] Table 2

[0063]

[0064] Table 3

[0065]

[0066]

[0067] It can be seen from Tables 1 to 3 that the embodiments of the present invention adjust the chemical composition of the resonance sheet, reduce or even eliminate cobalt and nickel, and control the heat treatment temperature to below 310°C. The resonance sheet prepared is used for the acoustomagnetic tag, which can make the resonance frequency of the acoustomagnetic tag more stable and have good anti-theft alarm performance.

[0068] Compared with Example 13, the heat treatment temperature of Comparative Example 1 is increased to not less than 375°C, and the heat treatment time is greater than 15s, but the resonance stability of its acoustomagnetic tag is significantly worse than that of Example 13, which indicates that the resonance sheet obtained by heat treatment at a lower temperature of the present invention can make the resonance frequency of the acoustomagnetic tag more stable.

[0069] It should be understood that in the description of the present invention, the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0070] In the present invention, unless otherwise clearly specified and limited, the terms "set", "connection" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A resonance sheet for manufacturing an anti-theft label, characterized in that: The invention comprises the following components in weight percentage: nickel 0-31%, cobalt 0-15%, molybdenum 1-12%, other transition metals 0-8%, boron 1-16%, silicon 0-6%, phosphorus 0-1%, aluminum 0-2%, carbon 0-2%, and iron as the remainder, wherein the other transition metals are transition metals other than iron, nickel, cobalt and molybdenum.

2. The resonance piece according to claim 1, characterized in that The width of the resonance plate is 2-7 mm.

3. A method for preparing a resonance sheet as claimed in any one of claims 1 to 2, characterized in that: The steps include: S1, preparing a quenched amorphous ribbon; S2. heat-treating the quenched amorphous ribbon at a temperature of 200-309° C. to obtain a resonance plate.

4. The method for preparing a resonance sheet according to claim 3, characterized in that: The temperature of the heat treatment is 220 to 306°C, more preferably 260 to 305°C, and even more preferably 269 to 300°C.

5. The method for preparing a resonance sheet as claimed in claim 3, characterized in that: The heat treatment time is 3 to 15 seconds.

6. The method for preparing a resonance sheet according to claim 3, characterized in that: The magnetic field intensity of the heat treatment is 0-2000 Gs.

7. An acoustic magnetic tag, characterized in that: The invention comprises a shell, a biasing member and a resonance piece as claimed in any one of claims 1 to 4; the resonance piece is arranged in the inner cavity of the shell, and the biasing piece is arranged on the outer side or the inner side of the shell.

8. The acousto-magnetic tag according to claim 7, characterized in that: The resonance frequency of the acoustomagnetic tag is 57.5-58.5 kHz.

9. The acousto-magnetic tag according to claim 7, characterized in that: The number of resonance sheets in the acousto-magnetic tag is 1 to 7 sheets, and the total weight of the resonance sheets contained in the acousto-magnetic tag is 0.05 to 0.11 g.

10. The acousto-magnetic tag according to claim 7, characterized in that: The biasing member is in sheet or wire form.

Images