JP2011156481A - Ultrasonic atomizing device and equipment provided with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic atomizing device which can atomize a liquid in a wide range and can stably supply the atomizing amount, and equipment provided with the ultrasonic atomizing device. <P>SOLUTION: The ultrasonic atomizing device 100 includes a Langevin type ultrasonic transducer 10 which is provided with a piezoelectric element 11, and a vibrating plate 13 which has an area larger than the ultrasonic transducer 10, is attached to one end of the ultrasonic transducer 10, and vibrates at a vibration frequency coinciding with the resonance frequency of the ultrasonic transducer 10 to generate ultrasonic waves. The liquid is supplied to the vibrating plate 13, whereby the liquid is atomized and emitted. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ultrasonic atomizer that atomizes and radiates a liquid into the air, and a facility device including the same.

  Conventionally, there has been an ultrasonic generator using a piezoelectric element such as PZT (lead zirconate titanate). In general, such an ultrasonic generator oscillates a piezoelectric element by applying a voltage to the piezoelectric element, and oscillates a specific frequency by using a resonance frequency of vibration in a certain direction. It has become. An ultrasonic atomizing apparatus having a horn structure that atomizes a liquid by utilizing such ultrasonic vibration has been reported.

  As such, “a vibrator that generates vibration by applying a high-frequency voltage, and one end of which is connected to the vibrator to increase the vibration amplitude of the vibrator, There is an ultrasonic atomizer "that includes a horn that outputs the vibration of the above and a liquid reservoir holder that holds the liquid supplied to the horn at the tip of the horn (see, for example, Patent Document 1). In this ultrasonic atomizer, the liquid distributed to the liquid reservoir holder is uniformly introduced into the liquid reservoir holder by a predetermined liquid distributor. As a result, not only a relatively highly permeable liquid such as alcohol but also a liquid such as water can be atomized uniformly.

  In addition, there is an ultrasonic atomization device that introduces a circuit that can adjust the voltage applied to the vibrator with the same atomization configuration as described above (see, for example, Patent Document 2). In this ultrasonic atomization apparatus, the vibration amplitude of the horn can be adjusted by adjusting the voltage applied to the vibrator, and thereby the atomization range can be adjusted.

Japanese Utility Model Publication No. 5-95673 (FIG. 1) JP-A-8-215621 (3rd, 4th page, FIG. 5)

However, the following problems exist in the conventional ultrasonic atomizer as described in Patent Document 1 and Patent Document 2.
(1) The problem that the atomization area is small In the case of an ultrasonic vibrator structure equipped with a horn, the vibration of only the tip part has a structure that obtains a large amplitude, and a place to obtain the atomization amount by an appropriate atomization state However, it was limited to the horn tip. As a result, the atomization range was narrowed, and the amount of atomization that could be supplied was small.

(2) Problems that impurities exert on stable vibration The tip of the horn is always in contact with the liquid. Therefore, when the object to be atomized is general tap water, a calcium component contained in the water adheres to the tip portion of the horn and causes a phenomenon that the tip portion of the horn increases in weight. As a result, the tip of the horn does not vibrate, and as a result, the liquid does not atomize. In cases other than general tap water, chlorine contained in moisture and impurities in the water adhere to the tip of the horn, similarly reducing the vibration output and making it impossible to atomize the liquid. In addition, when the vibration output is reduced, the liquid cannot be stably atomized, and wasteful liquid is supplied.

  As described above, in the configuration of the conventional ultrasonic atomizer, it is difficult to stably supply the atomization amount in a wide atomization range.

  The present invention has been made in order to solve the above-described problems. An ultrasonic atomization apparatus capable of atomizing a liquid in a wide range and achieving a stable supply of an atomization amount and the same The purpose is to provide equipment and equipment.

  An ultrasonic atomization apparatus according to the present invention has a Langevin type ultrasonic vibrator provided with a piezoelectric element, and has a larger area than the ultrasonic vibrator, and is attached to one end of the ultrasonic vibrator. A vibration plate that vibrates at a frequency that matches the resonance frequency of the ultrasonic transducer and generates ultrasonic waves, and is disposed at a position opposite to the surface side of the vibration plate on which the ultrasonic transducer is not attached. A liquid holding filter that holds the liquid supplied to the diaphragm and generates a surface tension between the liquid and the diaphragm, and supplies the liquid to the liquid holding filter. The liquid is atomized and emitted.

  According to the ultrasonic atomizing apparatus of the present invention, it is possible to atomize a liquid in a wide range, and to stably supply the atomization amount.

It is a block diagram which shows schematic structure of the ultrasonic atomizer which concerns on Embodiment 1 of this invention. It is explanatory drawing for demonstrating the vibration mode of a diaphragm. It is explanatory drawing for demonstrating the vibration mode when it becomes a rectangle when planarly viewing a diaphragm. It is explanatory drawing for demonstrating a vibration mode when it becomes circular when a diaphragm is planarly viewed. It is explanatory drawing for atomizing and radiating a liquid, without using the filter for liquid retention in an ultrasonic atomizer. It is explanatory drawing of atomization when a diaphragm and a liquid retention filter are bent into a fan-shaped arc shape in order to make the atomization range wide. It is a graph for demonstrating the resonance of an ultrasonic transducer | vibrator and a diaphragm. It is a graph which shows the relationship between the diameter of the opening of the filter for liquid retention, the diameter of the water atomized and emitted, and the frequency of the ultrasonic transducer. It is a graph which shows the relationship between the time which sterilizes a finger, and sterilization power, when the liquid atomized with an ultrasonic atomizer is used as sterilization liquid. It is a graph which shows the relationship between the diameter (filter diameter) of the opening of a filter for liquid retention, and sterilization power.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
FIG. 1 is a configuration diagram showing a schematic configuration of an ultrasonic atomizer 100 according to Embodiment 1 of the present invention. Based on FIG. 1, the structure of this ultrasonic atomizer 100 is demonstrated. In addition, in the following drawings including FIG. 1, the relationship of the size of each component may be different from the actual one.

  As shown in FIG. 1, the ultrasonic atomizer 100 includes at least an ultrasonic transducer 10, a piezoelectric element 11, and a diaphragm 13. The dotted line 12 is a visual representation of the vibration mode of longitudinal vibration that occurs inside the ultrasonic transducer 10. The vibration mode is set so that the antinode of the vibration mode corresponds to the end of the ultrasonic transducer 10. FIG. 1 shows an example in which the ultrasonic vibrator 10, the piezoelectric element 11, and the diaphragm 13 are mounted in the housing 1. Further, the dotted line 55 is a visual representation of “antinodes” and “nodes” of vibrations generated in the diaphragm 13.

  The ultrasonic transducer 10 is a Langevin type transducer. The piezoelectric element 11 is made of PZT (lead zirconate titanate). The piezoelectric element 11 is provided in the ultrasonic transducer 10. The diaphragm 13 is made of a plate material having an arbitrary shape that is fixed to the end (the lower end in FIG. 1) of the ultrasonic transducer 10. As shown in FIG. 1, the vibration plate 13 is disposed so as not to come into contact with any part other than a fixed point with the ultrasonic transducer 10. In addition, the diaphragm 13 has an area larger than the area of the end of the ultrasonic transducer 10.

  The ultrasonic atomizer 100 further includes a liquid holding filter 14. The liquid holding filter 14 is disposed on the surface side of the vibration plate 13 on which the ultrasonic transducer 10 is not fixed (the lower surface in FIG. 1) so as to face the vibration plate 13. The liquid holding filter 14 is formed with an arbitrary number of apertures 16 arranged in a uniform manner. The opening 16 is formed in the liquid holding filter 14 with an arbitrary diameter. The liquid holding filter 14 is molded from a nonwoven material or a foam material, and has a thickness of 1 mm or less, for example. The outer peripheral end 30 of the liquid holding filter 14 is disposed at a position where it is fixed in contact with the inner wall of the housing 1.

  FIG. 1 shows an example in which a liquid supply device 15 that supplies liquid to the liquid holding filter 14 is mounted in the housing 1. The liquid supply device 15 only needs to be installed at a position where the liquid can be supplied to the liquid holding filter 14, and is not limited to being mounted in the housing 1. Further, the number of liquid supply devices 15 is not limited to one, and may be an arbitrary number.

  Next, the operation of the ultrasonic atomizer 100 will be described. When the voltage is applied to the piezoelectric element 11, the ultrasonic atomizer 100 starts operating. The piezoelectric element 11 vibrates when a voltage is applied. The vibration is transmitted to the ultrasonic transducer 10, and the ultrasonic transducer 10 vibrates (dotted line 12). The vibration of the ultrasonic transducer 10 propagates to the diaphragm 13 and the diaphragm 13 vibrates (dotted line 55). Under the vibration of the diaphragm 13, the liquid held in the liquid holding filter 14 is atomized and radiated to the outside from the opening 16 of the liquid holding filter 14.

  The relationship between the resonance vibration of the ultrasonic vibrator 10 and the diaphragm 13 and atomization will be described. The ultrasonic vibrator 10 and the diaphragm 13 each have a natural frequency depending on the shape and material. The material and shape can be determined so that the natural frequencies of the ultrasonic transducer 10 and the diaphragm 13 coincide. Then, the ultrasonic vibrator 10 and the diaphragm 13 are caused to resonate by being vibrated at the matched natural frequency. Due to this resonance vibration, a dense wave with “antinode” and “node” is generated in the diaphragm 13. Thereby, powerful ultrasonic waves are uniformly emitted from the entire surface of the diaphragm 13. Upon receiving this ultrasonic wave, the liquid held in the liquid holding filter 14 is atomized.

  The liquid supply and holding will be described. The liquid is set so that a certain amount is supplied from the liquid supply device 15. The liquid supply device 15 is provided with an electromagnetic pump (not shown), and can automatically supply liquid to the liquid supply device 15. The liquid holding filter 14 and the diaphragm 13 holding the liquid supplied from the liquid supply device 15 are in a state of being naturally stuck due to the surface tension of the liquid. Further, the opening 16 formed in the liquid holding filter 14 can also hold the liquid by the surface tension. The liquid held in the opening 16 is radiated to the outside of the opening 16 by ultrasonic waves generated by the vibration of the diaphragm 13.

  FIG. 2 illustrates the vibration mode of the diaphragm 13. The vibration modes that can be applied by the ultrasonic atomizer 100 are the vibrations evenly in the left-right and up-down directions on the plane of the vibration plate 13 with the ultrasonic vibrator 10 fixed to the center of the vibration plate 13 as a boundary ( Wave) is generated, and the phase condition is also equal in the horizontal and vertical directions. As a result, a sparse wave consisting of a sparse part (node) and a dense part (antinode) is generated on the vibration surface of the diaphragm 13.

  FIG. 2 shows an example in which the diaphragm 13 that can be molded into an arbitrary shape is a square (a square when the diaphragm 13 is viewed in plan). When the diaphragm 13 is molded in this way, the vibration of the diaphragm 13 appears as a lattice mode as shown in FIG. There are two types of lattice modes (A) and (B), and both vibration modes can be applied to the ultrasonic atomizer 100. (A) shows a lattice-like vibration mode oblique to each side L1 and L2 when the diaphragm 13 is viewed in plan, and (B) shows each side L1 and L2 when the diaphragm 13 is viewed in plan. A lattice-like vibration mode that is generated in parallel is shown.

  In the lattice-like vibration mode, a dense wave is formed on the surface of the diaphragm 13 as viewed in plan. The sparse part (node) and the dense part (antinode) are very many, and the lattice-like vibration mode that occurs uniformly over the entire surface of the diaphragm 13 in plan view occurs in a high frequency band.

In addition, the generation condition of the lattice-like vibration mode is determined by the following factors.
(1) The dimension of one side that determines the diaphragm shape and the thickness of the diaphragm.
(2) Elastic modulus and Young's modulus determined from the specifications of a metal plate such as aluminum or SUS, which is a material of the diaphragm.

  FIG. 7 explains the resonance of the ultrasonic transducer 10 and the diaphragm 13. In FIG. 7, the vertical axis represents the sharpness Q, and the horizontal axis represents the frequency. The sharpness Q is an index representing the sound pressure level, and the larger the value, the higher the sound pressure level. In FIG. 7, the curve (A) indicates the natural vibration characteristic of the diaphragm 13, the curve (A) indicates the natural vibration characteristic of the ultrasonic transducer 10, and the curve (C) indicates the vibration plate 13 and the ultrasonic transducer 10. The resonance frequency characteristics are shown.

  As shown in FIG. 7, when the natural frequencies of the ultrasonic vibrator 10 and the diaphragm 13 are set to coincide with each other and are vibrated at the natural frequency, the ultrasonic vibrator 10 and the diaphragm 13 resonate and sharp. It can be seen that the degree Q becomes sharper. This indicates that a stronger sound pressure is radiated from the diaphragm by causing the ultrasonic vibrator 10 and the diaphragm 13 to resonate. That is, it is shown that the liquid can be atomized strongly by resonating the diaphragm 13 and the ultrasonic transducer 10.

  FIG. 8 is a graph showing the relationship between the diameter of the opening 16 of the liquid holding filter 14, the diameter of the water atomized and emitted, and the frequency of the ultrasonic transducer 10. In FIG. 8, the vertical axis indicates the diameter (mm) of the aperture 16 formed in the liquid holding filter 14, the horizontal axis indicates the water diameter (mm) that is atomized and radiated, and the horizontal axis indicates the ultrasonic transducer 10. The frequency (kHz) of each is expressed.

  FIG. 8 shows that the diameter of the aperture 16 and the water diameter at the time of atomization have a first-order correlation. Further, the water diameter at the time of atomization and the vibration frequency of the ultrasonic vibrator 10 have a correlation. For example, when the ultrasonic vibrator 10 is vibrated at 20 kHz, the water diameter at the time of atomization is about 0.1 mm, and when vibrated at 50 kHz, the water diameter at the time of atomization is about 0.001 mm. Therefore, the diameter of the opening 16 is set to 0.001 mm to 0.1 mm according to the water diameter at the time of atomization. Thus, by making the water diameter to be atomized substantially coincide with the diameter of the aperture 16, the liquid can be uniformly atomized and radiated.

  FIG. 9 shows the relationship between the sterilization time (sec) and the sterilization power when the atomized liquid has a sterilization function. Here, it is assumed that the liquid atomized and radiated by the ultrasonic atomizer 100 is, for example, an aqueous solution of about 70% methyl alcohol, and the supplied amount is 1 cc to 3 cc. In FIG. 9, the horizontal axis represents the time (sec) for sterilizing the fingers, and the vertical axis represents the sterilization power (%), which is an index indicating how much the fingers are sterilized. If the output of the ultrasonic wave emitted from the diaphragm 13 is sufficient, it may be considered that the sterilizing liquid can be atomized and emitted instantaneously. It can be seen that when atomizing radiation from the entire surface of the diaphragm 13 to the fingers, sterilization of almost 100% is possible within 2 seconds.

  When the object to be sterilized is a human hand or finger, the size of the diaphragm 13 is set to be equal to or larger than the size in which both fingers are arranged (a square whose side is within 20 cm to 25 cm, for example). Fingers can be sterilized at once.

  FIG. 10 shows the relationship between the diameter of the aperture 16 of the liquid holding filter and the sterilizing power. In FIG. 10, the horizontal axis represents the diameter (mm) of the aperture 16 of the liquid holding filter, and the vertical axis represents the sterilizing power (%) serving as an index indicating how much sterilization is performed. If the diameter of the opening 16 is too large, the diameter of the atomized liquid also increases, making it difficult for the fingers to enter the wrinkles. Thereby, the sterilizing power is reduced. Moreover, even if the filter diameter is too small, the sterilizing power is reduced. From this graph, it can be seen that the optimal diameter of the aperture 16 of the liquid holding filter 14 is 0.1 mm in order to sterilize the fingers.

In addition, the following is possible.
(1) Optimization of the amount of sterilizing liquid and reduction of wasteful sterilizing liquid.
(2) Reduction of power consumption by reducing ultrasonic transducer drive time.

  As described above, in the ultrasonic atomizing apparatus 100 according to Embodiment 1, it is possible to atomize a liquid in a wide range, and to stably supply the atomization amount. Moreover, if such an ultrasonic atomizer 100 is provided in equipment (for example, a sterilizer, a humidifier, a vacuum cleaner, etc.), the liquid can be similarly atomized in a wide atomization range. Can be stably supplied. In the first embodiment, water and sterilized water are exemplified as the liquid to be atomized. However, the liquid is not limited thereto, and may be determined according to the use of the ultrasonic atomizer 100.

Embodiment 2. FIG.
FIG. 3 shows a state of the vibration mode when the shape of the diaphragm 13 in plan view is a rectangle. FIG. 4 shows the vibration mode of the diaphragm having a circular shape when the diaphragm 13 is viewed in plan. Based on FIG.3 and FIG.4, the characteristic matter of the ultrasonic atomizer which concerns on Embodiment 2 is demonstrated. In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and differences from the first embodiment will be mainly described.

  As shown in FIG. 3, the ultrasonic transducer 10 is fixed at a position where the diagonal lines of the rectangular diaphragm 13 intersect. For example, when the relationship between the lengths of the short side and the long side is 1: 1.5 to 3, the vibration mode is a ladder-like divided vibration mode as shown in FIG.

  When this diaphragm structure is applied to the ultrasonic atomizer 100 and used as a sterilizer for a sterilizer using a sterilizer, the long diaphragm structure can be used effectively, such as kitchen “chopping boards” and “vegetables”. Application to sterilization is conceivable. Moreover, when using as an atomizer, it is applicable to the humidification air supply to a big room.

  As shown in FIG. 4, the ultrasonic atomizer 100 is fixed to the center position of the circular diaphragm 13. As a result, a vibration mode centering on the ultrasonic transducer 10 fixed to the center of the diaphragm 13 is generated on the entire surface of the circular diaphragm 13. In FIG. 4, the dotted line indicates the “antinode” portion of the vibration mode.

  The circular diaphragm 13 can also be applied to a sterilizer. For example, it can be used to sterilize “fruit”. Of course, application to a general sterilizer is also conceivable.

  As described above, in the ultrasonic atomizing apparatus 100 according to Embodiment 2, it is possible to atomize a liquid over a wide range, and to stably supply the atomization amount. Moreover, if such an ultrasonic atomizer 100 is provided in equipment, the liquid can be similarly atomized in a wide range, and stable supply of the atomization amount can be achieved.

Embodiment 3 FIG.
FIG. 5 shows a state where the liquid is atomized by the diaphragm 13 itself. Based on FIG. 5, the characteristic matter of the ultrasonic atomizer which concerns on Embodiment 3 is demonstrated. In the third embodiment, the same reference numerals are given to the same parts as those in the first and second embodiments, and differences from the first and second embodiments will be mainly described.

  The diaphragm 13 is formed with pores 50 having a size that allows liquid to flow back and forth. The pore 50 is formed so as to coincide with the antinode portion of the vibration (dotted line 55) generated in the diaphragm 13. A liquid supply port 56 of the liquid supply device 15 is installed in the pore 50 at a position that is approximately half the thickness of the diaphragm, and an arbitrary amount of liquid is supplied to the pore 50.

  The liquid supplied to the pore 50 is held in or near the pore 50 by surface tension. The vibration of the ultrasonic vibrator 10 propagates to the diaphragm 13, and the diaphragm 13 vibrates. The entire diaphragm including the pores 50 vibrates under a uniform phase condition to generate ultrasonic waves. Along with this, the moisture retained in the pores 50 is released all at once. In this structure, there is a proportional relationship between the size of the pores and the atomized water diameter. For example, when the diameter of the pores 50 is 0.1 mm, a mist having a water diameter of about 0.1 mm is emitted.

  Since the entire amount of the liquid is atomized and released when the vibration plate 13 vibrates, the water inside the pore 50 is empty until the liquid once discharged from the pore 50 is supplied again from the liquid supply device 15 to the pore 50. It becomes the state of. Thereby, the problem that the pores 50 are blocked by the influence of calcium or chalk contained in the liquid does not occur. Therefore, it is possible to always supply atomized stably. Although the liquid holding filter 14 is not shown in FIG. 5, it goes without saying that the liquid can be held more efficiently if the liquid holding filter 14 is used.

  As described above, in the ultrasonic atomization apparatus 100 according to Embodiment 3, it is possible to atomize a liquid in a wide range, and to stably supply the atomization amount. Moreover, if such an ultrasonic atomizer 100 is provided in equipment, the liquid can be similarly atomized in a wide range, and stable supply of the atomization amount can be achieved.

Embodiment 4 FIG.
FIG. 6 shows a state when atomizing and radiating with an ultrasonic atomizer when the diaphragm 13 is formed in a fan-shaped arc shape having an arbitrary angle with respect to the atomization direction. Is. Based on FIG. 6, the characteristic matter of the ultrasonic atomizer which concerns on Embodiment 4 is demonstrated. In the fourth embodiment, the same reference numerals are given to the same parts as those in the first to third embodiments, and differences from the first to third embodiments will be mainly described.

  The shape of the diaphragm 13 is a square or a rectangle (the shape in a state where the diaphragm 13 is viewed in plan is a square or a rectangle). Further, in order not to divide the vibration mode of the diaphragm 13, the diaphragm 13 is formed into a fan shape, and the inner angle of the fan shape is set in a range of 120 degrees to 170 degrees. The liquid supply can be applied by means for radiating after holding the water by the liquid holding filter 14 or by means for directly forming the liquid supply port 56 in the diaphragm 13. This arc shape makes it possible to atomize and radiate liquid over a wide range.

  As described above, in the ultrasonic atomization apparatus 100 according to Embodiment 4, it is possible to atomize a liquid in a wide range, and to stably supply the atomization amount. Moreover, if such an ultrasonic atomizer 100 is provided in equipment, the liquid can be similarly atomized in a wide range, and stable supply of the atomization amount can be achieved.

  As described above, since the ultrasonic atomization apparatus 100 described in each embodiment can stably supply the atomization, the ultrasonic atomization apparatus 100 is not limited to being used in a sterilizer, but is installed in a vacuum cleaner, for example, to assist in agglomerating dust. It includes application to functions, paint sprayers and even cleaning effects.

  DESCRIPTION OF SYMBOLS 1 Case, 10 Ultrasonic vibrator, 11 Piezoelectric element, 12 Vibration mode of ultrasonic vibrator, 13 Arbitrary-shaped vibration plate, 14 Liquid holding filter, 15 Liquid supply device, 16 Open hole, 50 Fine hole, 55 Vibration mode of diaphragm, 56 liquid supply port, 100 ultrasonic atomizer.

Claims (8)

A Langevin type ultrasonic transducer provided with a piezoelectric element;
The ultrasonic transducer has a larger area, is attached to one end of the ultrasonic transducer, vibrates at a frequency that matches the natural frequency of the ultrasonic transducer, and generates ultrasonic waves. A diaphragm,
A liquid holding filter that is disposed at a position facing the surface side of the diaphragm on which the ultrasonic vibrator is not attached, holds a liquid, and the liquid that is held contacts the diaphragm;
An ultrasonic atomizing apparatus characterized in that the liquid held by the liquid holding filter is atomized and emitted by ultrasonic waves generated by the diaphragm. The liquid holding filter is:
2. The ultrasonic atomizer according to claim 1, wherein the nonwoven fabric material or the foam material is molded, the plurality of apertures are uniformly arranged, and has a thickness of 1 mm or less. The ultrasonic atomizer according to claim 1, further comprising a plurality of liquid supply devices that supply liquid to the liquid holding filter. The ultrasonic atomizing device according to claim 3, wherein the diameter of the opening of the liquid holding filter is set to any one of 0.001 mm to 0.1 mm. A Langevin type ultrasonic transducer provided with a piezoelectric element;
The ultrasonic transducer has a larger area, is attached to one end of the ultrasonic transducer, vibrates at a frequency that matches the natural frequency of the ultrasonic transducer, and resonates to generate ultrasonic waves. A diaphragm,
The diaphragm is formed with a plurality of pores capable of holding a liquid in accordance with a wavelength interval of a vibration mode corresponding to the shape thereof, the pore holds the liquid, and the liquid is generated by the diaphragm. An ultrasonic atomizing device, characterized by being atomized and emitted by ultrasonic waves. The diaphragm is
It consists of a square, a rectangle, or a circle and has a vibration mode according to its shape. The ultrasonic atomizer of Claim 1 or 5. The ultrasonic atomizer according to any one of claims 1 to 6, wherein the diaphragm has a fan-shaped arc shape with an inner angle in a range of 120 degrees to 170 degrees. The equipment provided with the atomization apparatus in any one of Claims 1-7.

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