Sample liquid atomizing device and analyzing device

Abstract

A sample liquid atomization device according to this invention comprises a first pipeline part (10) that is a tubular member and an ultrasonic sample-liquid-atomization unit (5) that comprises a vibration unit (3) for producing ultrasonic vibration, a vibration surface (1) that is vibrated by the vibration unit (3), a vibration member (2) comprising the vibration surface (1), and a pipe (7a) for supplying sample liquid (7) to the vibration surface (1), the ultrasonic sample-liquid-atomization unit (5) being for using the ultrasonic vibration of the vibration surface (1) to atomize the sample liquid (7) supplied to the vibration surface (1). The first pipeline part (10) extends in the direction of the ultrasonic vibration of the vibration surface (1). The ultrasonic sample-liquid-atomization unit (5) is provided inside the first pipeline part (10) and is supported in the first pipeline part (10) by a holding member (11).

Description

[Technical field]

[0001] The present invention relates to a sample liquid atomization device that atomizes a sample liquid, and an analysis device that includes the sample liquid atomization device. [Background technology]

[0002] In order to analyze a liquid containing sample components (sample liquid), a device is used that separates the liquid components in the sample liquid and introduces them into an analysis section. A typical example of an analysis device that separates and analyzes the sample components contained in the sample liquid is a liquid chromatography-mass spectrometry device.

[0003] In liquid chromatography-mass spectrometry, the sample liquid containing various components separated by liquid chromatography is turned into microdroplets, which are then charged and heated to vaporize, generating ions of the sample components to be analyzed. The ionized sample components are then introduced into a vacuum, separated according to their mass-to-charge ratio, and the components are identified. Methods for achieving this include electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI), and atmospheric pressure photoionization (APPI). Although these methods differ in the charging and heating methods, atmospheric pressure spraying is used to form the microdroplets. As an alternative to atmospheric pressure spraying, a method using ultrasound is also known, but there are many issues and it has not yet been put to practical use.

[0004] Patent Document 1 discloses a technique for forming finer droplets by combining an atmospheric pressure spray method with an ultrasonic vibrator.

[0005] Patent Document 2 discloses a technique in which a sample liquid stored in a container is vibrated by an ultrasonic vibrator to atomize the sample liquid and form droplets.

[0006] Non-Patent Document 1 describes the Lang equation, which shows the relationship between the diameter of droplets formed by ultrasonic waves and the vibration frequency of the ultrasonic waves. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 11-051902 [Patent Document 2] JP 2015-031650 A [Non-patent literature]

[0008] [Non-Patent Document 1] RJ Lang, Journal of the Acoustical Society of America, 1962, Vol. 34, p. 6 Summary of the Invention [Problem to be solved by the invention]

[0009] The atmospheric pressure spray method used in conventional liquid chromatography-mass spectrometry is a technique in which a liquid is divided into droplets by introducing the liquid into a high-speed jet. The atmospheric pressure spray used in liquid chromatography-mass spectrometry is required to divide the sample liquid into minute droplets with an average diameter of several μm to several tens of μm. For this reason, it is necessary to use an ultra-high-speed gas jet that is close to or exceeds the speed of sound.

[0010] The droplets formed by such ultra-high-speed gas jets tend to have unstable particle sizes and a wide particle size distribution. The particle size and particle size distribution of the droplets formed also affect the charging required for ionization and the subsequent vaporization process. Therefore, if the droplet size is unstable and the particle size distribution is wide, the state of the ions of the analytical components formed becomes unstable. Furthermore, since droplets formed by ultra-high-speed gas jets fly at such high speeds, it is difficult to ensure the heating time, and so they are generally heated to high temperatures of 500°C or more to vaporize them.

[0011] As described above, the ionization method of sample components using the atmospheric pressure spray method used in conventional liquid chromatography-mass spectrometry requires an ultra-high speed gas jet and high temperature, which makes the equipment complex and large-scale. Therefore, a method of ionizing sample components using a method other than the atmospheric pressure spray method is required.

[0012] On the other hand, ultrasonic atomization, which uses ultrasonic waves, is known as another method for turning liquid into microdroplets. Turning liquid into microdroplets using ultrasonic waves, or so-called atomization, is widely used in various fields such as ultrasonic humidifiers and painting. However, there are the following issues when using ultrasonic atomization in sample liquid analysis equipment such as liquid chromatography-mass spectrometry equipment.

[0013] First, liquids containing different sample components are continuously sent from the liquid chromatograph to the sample liquid atomizer through a thin tube with a diameter of a few hundred micrometers or less. The amount of sample liquid sent is extremely small, less than a few hundred microliters each. These sample liquids must be continuously atomized without mixing with sample liquids containing different sample components. Furthermore, the atomized droplets must be charged and vaporized by heating before being sent to the analysis section. For this reason, it is necessary to handle the small amount of atomized sample liquid with high precision. Also, in order to easily and stably perform vaporization by heating, it is advantageous to have smaller droplets.

[0014] The particle size of droplets formed by ultrasonic waves is affected by the vibration frequency of the ultrasonic waves as well as the liquid properties. It is known that the relationship between the vibration frequency and the particle size generally follows Lang's formula (Non-Patent Document 1). In liquid chromatography-mass spectrometry devices, water or alcohol is used as a solvent for the sample liquid. According to Lang's formula, the vibration frequency for vibrating water or alcohol to form droplets with a particle size of about 10 μm is about 200 to 300 kHz, and the vibration frequency for forming droplets with a particle size of 1 to 3 μm is several MHz.

[0015] In general, ultrasonic vibrators such as piezoelectric elements have a small vibration amplitude, so it is difficult to directly divide and atomize liquid. For this reason, the amplitude is expanded by utilizing the resonance phenomenon of metal columns or diaphragm structures, and vibrations with an acceleration that can divide liquid are obtained. In a typical ultrasonic vibration droplet forming device, the vibration frequency is limited to about several hundred kHz because the vibration frequency is utilized by using the resonance vibration of metal. As described above, the droplet diameter sprayed by the atmospheric pressure spray used in the conventional mass spectrometer is about several μm to several tens of μm. Also, as explained using the Lang formula, the droplet diameter obtained by atomization by ultrasonic vibration of several hundred kHz is also about the same. For this reason, it is practically difficult to form finer droplets by combining the atmospheric pressure spray method with an ultrasonic vibrator.

[0016] Patent Document 1 discloses a configuration in which sample droplets are atomized in a relatively large chamber, and then the atomized sample droplets are transported by airflow to a desolvation chamber connected by a piping with a narrowing flow path, and then transported by airflow to an analyzer. In this configuration in which multiple chambers are connected by piping, the airflow becomes unstable, so there is a high possibility that the atomized sample droplets will adhere to the wall surface, etc. Furthermore, it can be easily inferred that there is a high possibility that sample liquids containing different sample components that are continuously supplied will be mixed together.

[0017] Another problem with ultrasonic transducers is heat generation during operation. If the temperature of an ultrasonic transducer rises, it will not be able to obtain sufficient vibration, and may even break. Patent Document 1 discloses a method of contacting a thermally conductive member with an ultrasonic transducer and cooling it with a Peltier element. However, this method has problems such as a complicated configuration for cooling, ultrasonic vibrations being affected by contact with the thermally conductive member, and the Peltier element for cooling requiring a large amount of power.

[0018] In the technology disclosed in Patent Document 2, the vibrating liquid itself is used to amplify the applied vibration force, and a part of the liquid is turned into fine droplets, that is, atomized. Unlike the above-mentioned method of expanding the amplitude by utilizing the resonance phenomenon of metals, this technology can vibrate the sample liquid at a vibration frequency of several MHz, and can form droplets with an average particle size of about several μm. However, this technology requires the liquid to be irradiated with ultrasonic waves to be stored in a container or the like, so a certain amount of liquid is required, and it is difficult to atomize a small amount of sample liquid that is continuously delivered from liquid chromatography. If the sample liquid is not stored in a container and a small amount of sample liquid is vibrated at a vibration frequency of several MHz, the vibrated sample liquid is expected to scatter, making it even more difficult to stably form fine droplets.

[0019] An object of the present invention is to provide a sample liquid atomization device capable of stably forming sample liquid into droplets, and an analytical device equipped with this sample liquid atomization device. [Means for solving the problem]

[0020] The sample liquid atomization device according to the present invention includes an ultrasonic sample liquid atomization unit that includes a vibration unit that generates ultrasonic vibrations, a vibration surface that is vibrated by the vibration unit, a vibration member that includes the vibration surface, and a pipe that supplies sample liquid to the vibration surface, and that atomizes the sample liquid supplied to the vibration surface by ultrasonic vibration of the vibration surface, and a first pipe section that is a tubular member. The first pipe section extends in the direction of ultrasonic vibration of the vibration surface. The ultrasonic sample liquid atomization unit is provided inside the first pipe section and is supported by a holding member on the first pipe section.

[0021] The analytical device according to the present invention includes the sample liquid atomization device according to the present invention. Effect of the Invention

[0022] According to the present invention, it is possible to provide a sample liquid atomization device capable of stably forming sample liquid into droplets, and an analysis device equipped with this sample liquid atomization device. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 shows an analysis device according to an embodiment of the present invention. [Figure 2A] FIG. 2 is a diagram showing the vicinity of the vibration surface of the ultrasonic sample liquid atomization unit. [Figure 2B] FIG. [Figure 2C] FIG. 2C is a diagram showing the vibration surface shown in FIG. 2B as viewed from above. [Figure 3A] FIG. 13 is a diagram showing the configuration of a vibration surface provided with a replaceable thin mesh plate, in which the thin mesh plate is held by a plate-shaped elastic body. [Figure 3B] FIG. 13 is a diagram showing the configuration of a vibrating surface equipped with a replaceable thin mesh plate, in which the thin mesh plate is held by a cap-shaped elastic body. [Figure 4A] FIG. 13 is a diagram showing an example of the configuration of a holding member for the atomization unit, the holding member holding the ultrasonic sample liquid atomization unit in a floating state. [Figure 4B]FIG. 13 is a diagram showing another example of the configuration of the atomization unit holding member, which is a diagram of a holding member that holds the ultrasonic sample liquid atomization unit in a floating state. [Figure 4C] FIG. 13 is a diagram showing another example of the configuration of the atomization unit holding member, which is a diagram of a holding member that holds the ultrasonic sample liquid atomization unit in a floating state. [Figure 4D] FIG. 13 is a diagram showing another example of the configuration of the atomization unit holding member, which is a diagram of a holding member that holds the ultrasonic sample liquid atomization unit at a position on the opposite side of the vibration surface with respect to the vibration unit. [Diagram 5] FIG. 1 is a diagram showing an example of an ultrasonic sample liquid atomization unit equipped with a cooling structure. [Figure 6A] 10A to 10C are diagrams showing examples of the configuration of the second duct section 3 that can shorten the length of the second duct section. [Figure 6B] FIG. 6B is a cross-sectional view of the cross section AA of FIG. 6A. [Figure 6C] FIG. 6B is a cross-sectional view of FIG. 6A. [Figure 7A] FIG. 2 is a diagram showing a configuration of a charge applying unit including a discharge wire. [Figure 7B] 1A and 1B are diagrams illustrating a configuration of a charge applying section including a needle-shaped member. [Figure 7C] FIG. 2 is a diagram showing a configuration of a charge applying unit including an ion emitting device. [Figure 8] 1A and 1B are diagrams showing the configuration of a charge imparting unit that imparts an electric charge to a sample component contained in a sample droplet when the sample liquid is atomized. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The sample liquid atomizer according to the present invention can convert a small amount of sample liquid continuously supplied from a liquid chromatograph or the like into fine droplets, i.e., atomize the sample liquid, and stably supply the sample liquid to an analysis section after subjecting the sample liquid to processing such as vaporization and charging. The analysis device according to the present invention is equipped with the sample liquid atomizer as an ion source, and can analyze the ionized sample components.

[0025] The sample liquid atomization device according to the present invention includes an ultrasonic sample liquid atomization unit for atomizing the sample liquid inside the first pipe section, and can continuously atomize the continuously supplied sample liquid with ultrasonic vibration. The ultrasonic sample liquid atomization unit is preferably held by a holding member that prevents the vibration of the ultrasonic sample liquid atomization unit from being transmitted to the first pipe section. In the first pipe section, a transport gas for transporting the atomized sample liquid, i.e., sample droplets, in the downstream direction preferably flows in the direction of the ultrasonic vibration. This transport gas also has the effect of cooling the ultrasonic sample liquid atomization unit.

[0026] When the ultrasonic sample liquid atomization unit is held so that the vibration of the ultrasonic sample liquid atomization unit is not transmitted to the first pipe section, the vibration of the first pipe section can be suppressed, and the atomization by ultrasonic vibration can be stably realized. Furthermore, when the transport gas for transporting the sample droplets flows in the direction of the ultrasonic vibration (the spray direction of the sample droplets), the sprayed sample droplets are transported stably inside the first pipe section on the transport gas, and can be prevented from adhering to the wall surface of the pipe section.

[0027] Hereinafter, a sample liquid atomization device and an analysis device according to an embodiment of the present invention will be described with reference to FIGS.

[0028] 1 is a diagram showing an analytical device according to an embodiment of the present invention. The analytical device according to this embodiment includes a sample liquid atomizer according to an embodiment of the present invention and an analysis unit 24 connected to the sample liquid atomizer, and is, for example, a mass spectrometer. The sample liquid atomizer according to this embodiment is used as an ion source for the analysis unit 24.

[0029] The sample liquid nebulizer according to the present embodiment includes a sample liquid nebulizer that nebulizes the sample liquid, a heating and vaporizing unit that heats and vaporizes the atomized sample liquid, and a charge imparting unit that imparts an electric charge to the sample components of the heated and vaporized sample liquid. The sample liquid nebulizer, the heating and vaporizing unit, and the charge imparting unit will be described below.

[0030] <Sample liquid atomization section> The sample liquid atomization section includes a first pipe section 10 and an ultrasonic sample liquid atomization unit 5 .

[0031] The first pipe section 10 is a tubular member and includes an ultrasonic sample liquid atomization unit 5. A sample liquid 7 and a carrier gas 8 are supplied to the first pipe section 10. The first pipe section 10 extends in the direction of ultrasonic vibration of the vibration surface 1 of the ultrasonic sample liquid atomization unit 5 (the direction perpendicular to the vibration surface 1, that is, the up-down direction in FIG. 1).

[0032] The ultrasonic sample liquid atomization unit 5 comprises a vibration section 3 that emits ultrasonic vibrations, a vibration member 2 that amplifies the ultrasonic vibrations generated by the vibration section 3, a vibration surface 1 mounted on the vibration member 2, and a pipe 7a through which a sample liquid 7 flows, and the sample liquid 7 supplied to the vibration surface 1 via the pipe 7a is atomized by the ultrasonic vibrations of the vibration surface 1.

[0033] The excitation unit 3 includes stacked piezoelectric elements, which are connected to a high-frequency drive circuit 6. The drive circuit 6 generates an AC voltage for ultrasonically driving the piezoelectric elements. The piezoelectric elements are ultrasonic transducers, and are driven at high frequency by the drive circuit 6 to generate ultrasonic vibrations.

[0034] The vibration member 2 has a vibration surface 1 at one end and a vibration unit 3 between the one end and the other end, and resonates when a piezoelectric element of the vibration unit 3 is driven at high frequency. The vibration member 2 can be made of, for example, a metal plate.

[0035] The vibration surface 1 is provided at one end of a vibration member 2, and is excited by a vibration unit 3. When the vibration member 2 resonates, the vibration surface 1 ultrasonically vibrates in a direction perpendicular to the vibration surface 1 (the vertical direction in FIG. 1).

[0036] The pipe 7a is a thin pipe for supplying the sample liquid 7 flowing from, for example, liquid chromatography to the ultrasonic sample liquid atomization unit 5, and is connected to the ultrasonic sample liquid atomization unit 5 via a connection part 4 provided on the ultrasonic sample liquid atomization unit 5. The pipe 7a is configured to pass through a hollow part provided in the center of the ultrasonic sample liquid atomization unit 5, reach the vibration surface 1, and supply the sample liquid 7 to the vibration surface 1.

[0037] The sample liquid 7 supplied to the vibrating surface 1 is divided into minute droplets by ultrasonic vibration in the vertical direction of the vibrating surface 1 (the up and down direction in FIG. 1), and is sprayed and ejected in the direction perpendicular to the vibrating surface 1 to be atomized. FIG. 1 shows sample droplets 14, which are the atomized sample liquid 7.

[0038] 2A to 2C are diagrams for explaining the configuration of the vicinity of the vibration surface 1 of the ultrasonic sample liquid atomization unit 5. Fig. 2A is a diagram showing the vicinity of the vibration surface 1 of the ultrasonic sample liquid atomization unit 5. Fig. 2B is an enlarged view of the vicinity of the vibration surface 1. Fig. 2C is a diagram showing the vibration surface 1 shown in Fig. 2B from above.

[0039] The vibration surface 1 of the ultrasonic sample liquid atomization unit 5 is capable of atomizing the supplied sample liquid 7 by ultrasonically vibrating in a direction perpendicular to the vibration surface 1. However, a small amount of sample liquid 7 tends to become larger droplets due to the influence of the surface tension of the liquid. For this reason, a portion of the sample liquid 7 supplied to the vibration surface 1 may scatter as large droplets, making it difficult to stably atomize the sample liquid 7.

[0040] As shown in FIG. 2B and FIG. 2C, the sample liquid atomization device according to this embodiment can have a mesh thin plate 27 on the surface of the vibration surface 1 to stably atomize the sample liquid 7.

[0041] The thin mesh plate 27 is a thin plate-like member arranged on the surface of the vibration surface 1, and includes a mesh portion having one or more fine holes 28. The thin mesh plate 27 is adhered and fixed to the vibration surface 1. The sample liquid 7 supplied to the vibration surface 1 spreads in the form of a thin liquid film between the vibration surface 1 and the thin mesh plate 27, and when the vibration surface 1 is ultrasonically vibrated, the sample liquid 7 is atomized and ejected from the fine holes 28 formed in the thin mesh plate 27, becoming sample droplets 14.

[0042] By providing the vibration surface 1 with the thin mesh plate 27, the sample liquid 7 is less susceptible to the effects of surface tension, making it possible to atomize the sample liquid 7 in an extremely stable manner.

[0043] When the vibrating surface 1 is provided with a thin mesh plate 27, the size of minute holes 28 formed in the thin mesh plate 27 affects the size of the atomized sample droplets 14. The size of the sample droplets 14 formed by ultrasonic vibration is basically affected by the ultrasonic vibration, but by using a thin mesh plate 27 with holes 28 having a small diameter, the particle size of the sample droplets 14 can be made smaller and sample droplets 14 with less variation in particle size can be formed.

[0044] The vibration frequency of the vibration surface 1 is, for example, slightly more than about 100 kHz. When the sample liquid 7 is atomized by ultrasonic vibration without using the thin mesh plate 27, the average particle size of the sample droplets 14 is about 10 μm. However, it has been confirmed that by using the thin mesh plate 27 with holes 28 having a diameter of several μm, sample droplets 14 having an average particle size of several μm can be generated with reduced variation in particle size.

[0045] The size and number of the fine holes 28 in the thin mesh plate 27 affect the amount of the formed sample droplets 14. For this reason, the size and number of the fine holes 28 need to be designed according to the amount of the sample liquid 7 to be supplied.

[0046] Also, sample liquid 7 containing different sample components may be continuously supplied to the vibration surface 1. If the gap between the vibration surface 1 and the thin mesh plate 27 is large, the continuously supplied sample liquids 7 containing different sample components are likely to mix with each other before being atomized. For this reason, it is preferable that the gap between the vibration surface 1 and the thin mesh plate 27 is as small as possible. In this embodiment, a recess is provided in the vibration surface 1, and the thin mesh plate 27 is adhered and fixed to this recess so that the gap between the vibration surface 1 and the thin mesh plate 27 is about 100 μm.

[0047] The thin mesh plate 27 does not have to be fixed by adhesion to the vibration surface 1. The thin mesh plate 27 having the fine holes 28 may become contaminated or the holes 28 may become clogged depending on the type of sample liquid 7 to be analyzed. For this reason, it is practically important to configure the ultrasonic sample liquid atomization unit 5 so that only the thin mesh plate 27 can be replaced.

[0048] 3A and 3B are diagrams showing the configuration of the vibration surface 1 equipped with a mesh thin plate 27 that can be replaced from the ultrasonic sample liquid atomization unit 5. FIG.

[0049] FIG. 3A is a diagram showing a configuration in which the thin mesh plate 27 is held by a plate-shaped elastic body 29a. The elastic body 29a has a shape that does not prevent the spraying of the sample droplets 14, and is supported by a holding frame 44 to hold the thin mesh plate 27. Although the holding frame 44 is not shown in FIG. 3A, it can be connected and fixed to, for example, the wall surface of the first pipe section 10 or the main body of the ultrasonic sample liquid atomization unit 5. However, the elastic body 29a provided between the thin mesh plate 27 and the holding frame 44 needs to fix the thin mesh plate 27 while appropriately contacting the vibration surface 1. If the contact of the elastic body 29a with the vibration surface 1 is unstable, the sample liquid 7 may leak from the vibration surface 1. In addition, if the elastic body 29a is pressed against the vibration surface 1 more than necessary, the ultrasonic vibration of the vibration surface 1 may become unstable.

[0050] FIG. 3B is a diagram showing a configuration in which the thin mesh plate 27 is held by a cap-shaped elastic body 29b. The cap-shaped elastic body 29b has a shape that does not prevent the spraying of the sample droplets 14, and covers the vibration surface 1 and the upper part of the vibration member 2 to hold the thin mesh plate 27. The vibration member 2 has a retaining portion 30 on the upper part, and the elastic body 29b is fixed by the retaining portion 30. When the thin mesh plate 27 is held by the cap-shaped elastic body 29b, it is necessary to consider the structure of the retaining portion 30 and the influence of the retaining portion 30 on vibration. It is also important to design the thin mesh plate 27 so that the gap between the vibration surface 1 and the thin mesh plate 27 is stable and remains at a preset value even if the thin mesh plate 27 is replaced.

[0051] Both the plate-shaped elastic body 29a and the cap-shaped elastic body 29b are detachable from the vibration surface 1. By removing the plate-shaped elastic body 29a and the cap-shaped elastic body 29b from the vibration surface 1, the mesh thin plate 27 can be replaced.

[0052] In the above, the configuration in which the piping 7a passes through a cavity provided inside the ultrasonic sample liquid atomization unit 5 and supplies the sample liquid 7 to the vibration surface 1 (or between the vibration surface 1 and the mesh thin plate 27) of the ultrasonic sample liquid atomization unit 5 has been described with reference to Figs. 1 to 3B. The piping 7a may be configured to supply the sample liquid 7 to the vibration surface 1 (or between the vibration surface 1 and the mesh thin plate 27) without passing through a cavity provided inside the ultrasonic sample liquid atomization unit 5. For example, the piping 7a may be configured to be made of a soft thin tube that does not affect the vibration of the vibration surface 1, reach the vibration surface 1 (or between the vibration surface 1 and the mesh thin plate 27) without passing through the inside of the ultrasonic sample liquid atomization unit 5, and directly supply the sample liquid 7 to the vibration surface 1.

[0053] Returning to Fig. 1, the ultrasonic sample liquid atomization unit 5 will be further described. The ultrasonic sample liquid atomization unit 5 is supported by an atomization unit holding member 11 on the inner wall surface of the first pipe line section 10 inside the first pipe line section 10. The ultrasonic sample liquid atomization unit 5 is preferably supported by the atomization unit holding member 11 at the center of the first pipe line section 10 in the radial direction.

[0054] The ultrasonic sample liquid atomization unit 5 is preferably held in a floating state by the atomization unit holding member 11. Being held in a floating state means that the ultrasonic sample liquid atomization unit 5 is supported so that the ultrasonic vibration of the ultrasonic sample liquid atomization unit 5 is not transmitted to the first duct section 10. In other words, the atomization unit holding member 11 that holds the ultrasonic sample liquid atomization unit 5 in a floating state is configured to support the ultrasonic sample liquid atomization unit 5 so that the ultrasonic vibration of the ultrasonic sample liquid atomization unit 5 is not transmitted to the first duct section 10.

[0055] The atomization unit holding member 11 connects the vibration member 2 of the ultrasonic sample liquid atomization unit 5 to the wall surface of the first duct section 10, and fixes the ultrasonic sample liquid atomization unit 5 to the first duct section 10. The atomization unit holding member 11 that holds the ultrasonic sample liquid atomization unit 5 in a floating state is a member that has a sufficiently low natural frequency relative to the vibration frequency of the ultrasonic sample liquid atomization unit 5, and is a member that holds the ultrasonic sample liquid atomization unit 5 softly with low rigidity. When the atomization unit holding member 11 has a soft holding structure with low rigidity, the ultrasonic vibration of the ultrasonic sample liquid atomization unit 5 is hardly transmitted to the first duct section 10, and the atomization unit holding member 11 can hold the ultrasonic sample liquid atomization unit 5 in a floating state or a state close to a floating state.

[0056] When the ultrasonic sample liquid atomization unit 5 is held in a floating state by the atomization unit holding member 11, the vibration energy of the vibration section 3 can be efficiently transmitted to the vibration surface 1, and the sample liquid 7 can be stably and efficiently atomized with low energy.

[0057] Figures 4A to 4D are diagrams showing configuration examples of the atomization unit holding member 11. Figures 4A to 4C show configuration examples of the atomization unit holding member 11 that holds the ultrasonic sample liquid atomization unit 5 in a floating state. Figures 4A to 4D also show the direction 31 of ultrasonic vibration of the vibration surface 1.

[0058] 4A is an atomization unit holding member 11 that holds the ultrasonic sample liquid atomization unit 5 in a floating state, and includes a thin rod-shaped member 33 and a spherical elastic rubber 32 provided at the tip of the rod-shaped member 33, and has flexibility and elasticity. The thin rod-shaped member 33 and the elastic rubber 32 are elastic members with lower rigidity than the vibration member 2.

[0059] The atomization unit holding member 11 shown in Fig. 4A is provided with an elastic rubber 32, and thus can hold the ultrasonic sample liquid atomization unit 5 so that ultrasonic vibrations generated in the ultrasonic sample liquid atomization unit 5 are not transmitted to the first duct section 10. Furthermore, the atomization unit holding member 11 shown in Fig. 4A has a thin rod-shaped member 33 with an elastic rubber 32 at its tip, so that the rod-shaped member 33 is easily bent in the direction 31 of ultrasonic vibration. The atomization unit holding member 11 in Fig. 4A is provided with an elastic rubber 32 and a thin rod-shaped member 33, and has flexibility and elasticity, so that it can hold the ultrasonic sample liquid atomization unit 5 in a floating state or a state very close to a floating state.

[0060] 4B is an atomization unit holding member 11 that holds the ultrasonic sample liquid atomization unit 5 in a floating state, includes a plate-shaped member 34, and is flexible. The length (thickness) of the plate-shaped member 34 in the ultrasonic vibration direction 31 is shorter than the length (width) in the direction perpendicular to the ultrasonic vibration direction 31. In other words, the plate-shaped member 34 is thin and has a width in the direction perpendicular to the ultrasonic vibration direction 31. The plate-shaped member 34 is an elastic member with lower rigidity than the vibration member 2.

[0061] The atomization unit holding member 11 shown in Fig. 4B has a thin thickness in the ultrasonic vibration direction 31 of the plate-like member 34, so that it has low rigidity in the ultrasonic vibration direction 31 and can hold the ultrasonic sample liquid atomization unit 5 in a floating state or a state very close to a floating state. Furthermore, the atomization unit holding member 11 shown in Fig. 4B has an advantage that the plate-like member 34 has a width in a direction perpendicular to the ultrasonic vibration direction 31, so that the effect of cooling the ultrasonic sample liquid atomization unit 5 by the gas (transport gas 8 flowing in the ultrasonic vibration direction 31) flowing around the ultrasonic sample liquid atomization unit 5 can be enhanced.

[0062] 4C is an atomization unit holding member 11 that holds the ultrasonic sample liquid atomization unit 5 in a floating state, and is a sliding member that includes a groove 36 provided in the ultrasonic sample liquid atomization unit 5 and a holding member 35 with one end located in the groove 36. That is, the atomization unit holding member 11 is composed of the holding member 35 that can slide relative to the groove 36 provided in the ultrasonic sample liquid atomization unit 5.

[0063] The groove 36 is a long and narrow groove extending in the ultrasonic vibration direction 31, and is provided in, for example, the vibration member 2. The length (width) of the holding member 35 in the ultrasonic vibration direction 31 is longer than the length (thickness) in the direction perpendicular to the ultrasonic vibration direction 31. In other words, the holding member 35 is thin and has a width in the ultrasonic vibration direction 31. When the ultrasonic sample liquid atomization unit 5 vibrates, the holding member 35 can move within the groove 36 while sliding against it.

[0064] The atomization unit holding member 11 shown in Fig. 4C can hold the ultrasonic sample liquid atomization unit 5 in a floating state or in a state very close to a floating state by sliding the holding member 35 against the groove 36. Furthermore, the atomization unit holding member 11 shown in Fig. 4C has an advantage that the ultrasonic sample liquid atomization unit 5 can be cooled without disturbing the flow of the gas (the transport gas 8 flowing in the ultrasonic vibration direction 31) flowing around the ultrasonic sample liquid atomization unit 5 because the thickness of the holding member 35 in the direction perpendicular to the ultrasonic vibration direction 31 is thin.

[0065] The atomization unit holding member 11 shown in FIGS. 4A to 4C is located between the vibration part 3 and the vibration surface 1 of the ultrasonic sample liquid atomization unit 5 and holds the ultrasonic sample liquid atomization unit 5 in a floating state.

[0066] The atomization unit holding member 11 shown in FIG. 4D is a holding member 37 that supports the ultrasonic sample liquid atomization unit 5 at a position opposite to the vibration surface 1 with respect to the vibration unit 3. The holding member 37 is, for example, a rigid member provided on the vibration member 2 and fixes the ultrasonic sample liquid atomization unit 5 to the first pipeline portion 10. The holding member 37 is connected to the vibration member 2 between the other end of the vibration member 2 (the end opposite to the end where the vibration surface 1 is installed) and the vibration unit 3. The holding member 37 is preferably streamlined in the ultrasonic vibration direction 31 so as not to disturb the flow of gas (transport gas 8 flowing in the ultrasonic vibration direction 31) flowing around the ultrasonic sample liquid atomization unit 5.

[0067] The atomization unit holding member 11 shown in Figure 4D can hold the ultrasonic sample liquid atomization unit 5 in a floating state by adjusting the vibration mode of the ultrasonic sample liquid atomization unit 5 so that there is almost no vibration of the holding member 37 located on the opposite side of the vibration surface 1 relative to the vibration section 3.

[0068] Returning to FIG. 1, the ultrasonic sample liquid atomization unit 5 will be described further.

[0069] The first pipeline section 10 has at one end a pipe 8a through which the transport gas 8 flows. The pipe 8a flows the transport gas 8 inside the first pipeline section 10. Inside the first pipeline section 10, the transport gas 8 supplied to the pipe 8a flows in the direction 31 of the ultrasonic vibration (FIGS. 4A to 4D). The transport gas 8 flows in the direction 31 of the ultrasonic vibration and transports the sample droplets 14 downstream.

[0070] The sample liquid atomization section is configured so that the carrier gas 8 flowing inside the first duct section 10 is supplied to the periphery of the ultrasonic sample liquid atomization unit 5 via the flow straightening section 9. The flow straightening section 9 can be configured, for example, by a flow straightening plate.

[0071] The transport gas 8 also has the effect of cooling the ultrasonic sample liquid atomization unit 5, which is heated by the ultrasonically vibrating piezoelectric element, by flowing around the ultrasonic sample liquid atomization unit 5. Since the ultrasonic sample liquid atomization unit 5 continuously atomizes the continuously supplied sample liquid 7, it is extremely important that it is cooled and efficiently discharges the heat generated by the ultrasonic waves. In order to effectively cool the ultrasonic sample liquid atomization unit 5, it is preferable that one or both of the ultrasonic sample liquid atomization unit 5 and the atomization unit holding member 11 are made of a material with high thermal conductivity, such as a metal.

[0072] The ultrasonic sample liquid atomization unit 5 can also be equipped with a cooling structure as shown in FIG.

[0073] Fig. 5 is a diagram showing an example of the ultrasonic sample liquid atomization unit 5 equipped with a cooling structure. Fig. 5 shows an example in which the ultrasonic sample liquid atomization unit 5 shown in Fig. 4C is equipped with a cooling structure. The ultrasonic sample liquid atomization unit 5 shown in Figs. 4A, 4B, and 4D can also be equipped with a cooling structure.

[0074] FIG. 5 shows an ultrasonic sample liquid atomization unit 5 having an uneven surface as a cooling structure. The uneven surface can be formed, for example, of a plurality of plate-like members 38 provided on the surface of the vibration member 2. The plate-like members 38 extend along the flow direction of the carrier gas 8 (direction of ultrasonic vibration 31), are thin, and act as cooling fins. When the vibration member 2 is made of a material with high thermal conductivity and has a plurality of thin plate-like members 38, the ultrasonic sample liquid atomization unit 5 can obtain a very high cooling effect. However, sufficient consideration must be given to the effect that the uneven surface (a plurality of plate-like members 38) as a cooling structure has on the ultrasonic vibration mode, etc.

[0075] Although not shown in the figure, the atomization unit holding member 11 may have an uneven surface (e.g., multiple plate-shaped members) as a cooling structure. Only one of the ultrasonic sample liquid atomization unit 5 and the atomization unit holding member 11 may have an uneven surface, or both may have uneven surfaces.

[0076] Returning to FIG. 1, the ultrasonic sample liquid atomization unit 5 will be described further.

[0077] The transport gas 8 is supplied from the end of the first pipe section 10 to the periphery of the ultrasonic sample liquid atomization unit 5 via the flow straightener 9, and has the effect of cooling the ultrasonic sample liquid atomization unit 5 and stably transporting the sample droplets 14 sprayed from the vibration surface 1 of the ultrasonic sample liquid atomization unit 5 along the first pipe section 10. Since the sample droplets 14 may contain flammable solvents such as alcohol, it is preferable to use an inert gas such as nitrogen or air as the transport gas 8. Using an inert gas as the transport gas 8 makes it possible to prevent the sprayed sample droplets 14 from igniting.

[0078] <Heat vaporization section> The thermal vaporization section will be described with reference to Fig. 1. In the following description, "downstream" refers to the flow direction with respect to the flow direction of carrier gas 8 (direction 31 of ultrasonic vibration).

[0079] The heating vaporization section includes a second pipe line section 13, and heats and vaporizes the sample droplets 14 atomized in the first pipe line section 10. The second pipe line section 13 is a tubular member, and one end of the second pipe line section 13 is connected to the first pipe line section 10 via a heat insulating connecting member 12. The second pipe line section 13 is located downstream of the first pipe line section 10, and is supplied with the sample droplets 14 atomized in the sample liquid atomization section.

[0080] The second pipe section 13 includes a heating section 15. The heating section 15 is configured to heat the wall surface of the second pipe section 13 in order to heat and vaporize the sample droplets 14 atomized by the sample liquid atomization section. The heating section 15 can include, for example, a heater connected to a power source 16. The heating section 15 heats the transport gas 8 that transports the atomized sample droplets 14, thereby heating and vaporizing the sample droplets 14. Although not shown in FIG. 1, the second pipe section 13 can also include a temperature detection section that detects the temperature of the second pipe section 13. The temperature detection section is configured to adjust the temperature of the second pipe section 13 to a predetermined temperature by controlling the heating section 15.

[0081] The first pipe line section 10 and the second pipe line section 13 are connected via a heat insulating connecting member 12, and the second pipe line section 13 is installed downstream of the first pipe line section 10. Therefore, the first pipe line section 10 is hardly affected when the second pipe line section 13 is heated. With this configuration, it is possible to efficiently cool the ultrasonic sample liquid atomization unit 5 arranged inside the first pipe line section 10 and heat and vaporize the atomized sample droplets 14 in the second pipe line section 13.

[0082] 1, the second pipe line section 13 is installed above the first pipe line section 10 in the direction of gravity. In this configuration, the transport gas 8 flows upward from the first pipe line section 10 to the second pipe line section 13, so that the heated transport gas 8 becomes an ascending air current, and it is possible to more efficiently separate and execute the cooling of the ultrasonic sample liquid atomization unit 5 and the heating and vaporization of the atomized sample droplets 14.

[0083] In addition, the sample liquid atomization device according to this embodiment does not have to be configured so that the second pipe line section 13 is not disposed above the first pipe line section 10 in the direction of gravity and the transport gas 8 flows upward from the first pipe line section 10 to the second pipe line section 13 due to restrictions on the configuration of the device. The second pipe line section 13 can be disposed at any position relative to the first pipe line section 10. Although there is a possibility that the energy efficiency may be reduced compared to the configuration shown in FIG. 1, the second pipe line section 13 can be disposed at any position relative to the first pipe line section 10 by appropriately adjusting the flow rate of the transport gas 8, the lengths of the first pipe line section 10 and the second pipe line section 13, the heating temperature by the heating section 15, and the like, and the atomization of the sample liquid 7 in the first pipe line section 10 and the heating and vaporization of the sample droplets 14 in the second pipe line section 13 can be effectively performed.

[0084] The second pipe section 13 is configured to heat and vaporize the sample droplets 14 by heating the transport gas 8 that transports the atomized sample droplets 14 with a heating section 15. If the atomized sample droplets 14 come into contact with the heated inner wall surface of the second pipe section 13, there is a risk that the sample components contained in the sample droplets 14 will be destroyed by the heat.

[0085] In the second pipe section 13, the wall surface is heated, so that the temperature of the wall surface is higher than that of the central portion in the radial direction, and the transport gas 8 heated at the wall surface becomes an ascending air current, and the flow rate of the gas 8 at the wall surface is faster than that of the gas 8 at the central portion in the radial direction. Since the flow rate of the transport gas 8 at the wall surface is faster than that at the central portion in the radial direction, the sample droplets 14 atomized at the central portion in the radial direction of the first pipe section 10 can be prevented from contacting the heated wall surface of the second pipe section 13. In addition, by appropriately setting the speed at which the transport gas 8 flows through the second pipe section 13, the flow rate of the transport gas 8 at the wall surface of the second pipe section 13 can be more effectively made faster than the flow rate at the central portion in the radial direction.

[0086] 1, in a configuration in which the second pipe section 13 is installed above the first pipe section 10 in the direction of gravity, and the transport gas 8 is heated on the wall surface of the second pipe section 13 to become an ascending air current and flow upward in the direction of gravity, the state in which the flow velocity of the transport gas 8 on the wall surface of the second pipe section 13 is faster than the flow velocity at the center in the radial direction can be more easily and stably maintained. From this point of view, the configuration in which the second pipe section 13 is installed above the first pipe section 10 in the direction of gravity is not essential, but it can be said to be a configuration with many advantages.

[0087] 1, for example, the ejection speed of the atomized sample droplets 14 can be set to several hundreds of mm / s, and the average flow speed of the transport gas 8 can be set to approximately 1 m / s, which is slightly faster than the ejection speed of the sample droplets 14. By setting the flow speed of the transport gas 8 to be approximately equal to or slightly faster than the ejection speed of the sample droplets 14 from the ultrasonic sample liquid atomization unit 5, the atomized sample droplets 14 are carried by the flow 17 of the transport gas 8 and smoothly and stably transported downstream in the second pipe section 13.

[0088] Furthermore, when the transport gas 8 is air or nitrogen, the inner diameter of the second pipe section 13 is several centimeters, and the flow rate of the transport gas 8 in the second pipe section 13 is about 1 m / s, the Reynolds number is also sufficiently small. That is, the transport gas 8 flows in a laminar state inside the second pipe section 13. In this embodiment, the nebulized sample droplets 14 are smoothly transported by the flow 17 of the transport gas 8 flowing in a laminar state, so that the sample droplets 14 formed by atomizing the sample liquid 7 containing different sample components that are continuously supplied are transported successively on the transport gas 8 without mixing with each other.

[0089] When the transport gas 8 flows in a laminar flow state through the second pipe section 13, it is heated by thermal conduction from the heated wall surface of the second pipe section 13 toward the radial center. In order to completely vaporize the sample droplets 14 transported by the transport gas 8, the temperature of the transport gas 8 at the radial center of the second pipe section 13 needs to be higher than the vaporization temperature of the solvent in the sample droplets 14.

[0090] It was confirmed that, when the inner diameter of the second pipe line section 13 is 2 cm, the temperature of the wall surface of the second pipe line section 13 is 500° C., and the length of the second pipe line section 13 is about 300 mm, the sample droplets 14 inside the second pipe line section 13 can be vaporized. When the flow velocity of the transport gas 8 inside the second pipe line section 13 is 1 m / s, the heating time is 300 ms, and it was confirmed that this heating time is almost consistent with the value estimated only from the heat transfer calculation of the transport gas 8. This agreement is due to the fact that the diameter of the atomized sample droplets 14 is small, 10 μm or less, and the amount of the sample droplets 14 is sufficiently small compared to the amount of the transport gas 8, so that the vaporization energy and vaporization time of the atomized sample droplets 14 can be almost negligible compared to the energy for heating the transport gas 8.

[0091] From the viewpoint of mounting the device, it is preferable that the length of the second pipe line section 13 is as short as possible. As described above, in order to vaporize the sample droplets 14, the temperature of the transport gas 8 must be higher than the vaporization temperature of the solvent of the sample droplets 14. Also, as described above, the transport gas 8 is used to cool the ultrasonic sample liquid atomization unit 5 in the first pipe line section 10. Therefore, in order to shorten the length of the second pipe line section 13, it is necessary to efficiently heat the transport gas 8 sent from the first pipe line section 10 in the second pipe line section 13.

[0092] As described above, in order to prevent the sample droplets 14 containing different sample components from mixing with each other, the transport gas 8 flows in a laminar state inside the second pipe line section 13. Therefore, the transport gas 8 inside the second pipe line section 13 is warmed by heat transfer from the heated wall surface of the second pipe line section 13, and the temperature decreases toward the center of the second pipe line section 13 in the radial direction.

[0093] Even if the length of the second pipe section 13 is short, the temperature of the transport gas 8 can be increased even in the radial center of the second pipe section 13 by, for example, the following three methods: increasing the heating temperature of the second pipe section 13, slowing the flow rate of the transport gas 8, and reducing the inner diameter of the second pipe section 13. The method of increasing the heating temperature of the second pipe section 13 is not preferred because it consumes a lot of energy. The method of slowing the flow rate of the transport gas 8 is not preferred because, as described above, a high flow rate is better for transporting the atomized sample droplets 14. In addition, the inner diameter of the second pipe section 13 cannot be made too small. This is because the second pipe section 13 needs an inner diameter corresponding to the first pipe section 10, and the first pipe section 10 needs an inner diameter large enough to hold the ultrasonic sample liquid atomization unit 5 inside. For example, when the outer diameter of the ultrasonic sample liquid atomization unit 5 is about 12 mm, the inner diameter of the first pipe section 10 and the second pipe section 13 is preferably 20 mm.

[0094] The sample liquid atomization device of this embodiment has the configuration shown in Figures 6A to 6C, so that the transport gas 8 can be efficiently heated in the second pipeline section 13 even if the length of the second pipeline section 13 is short.

[0095] Fig. 6A is a diagram showing an example of the configuration of the second pipe section 13 that can shorten the length of the second pipe section 13, and is a diagram showing a longitudinal section of the second pipe section 13. Fig. 6B is a diagram showing a section AA of Fig. 6A.

[0096] 6A and 6B, the second pipe section 13 has therein a partition wall 39 that divides the internal space into a plurality of spaces. The partition wall 39 extends in the direction of the flow 17 of the carrier gas 8, and divides the internal space of the second pipe section 13 into four spaces in the circumferential direction, for example, as shown in FIG. 6B.

[0097] By dividing the space inside the second pipe section 13 into a plurality of spaces by the dividing wall 39, the substantial inner diameter of the second pipe section 13 can be reduced, and the length of the second pipe section 13 can be shortened to shorten the distance required for the heat transfer of the transport gas 8. By providing the dividing wall 39 inside the second pipe section 13, even if the length of the second pipe section 13 is short, the transport gas 8 can be heated so that the temperature of the transport gas 8 becomes higher than the vaporization temperature of the solvent of the sample droplets 14.

[0098] It was confirmed that when a partition wall 39 was provided in the second pipe line section 13 having an inner diameter of 20 mm, dividing the internal space of the second pipe line section 13 into four as shown in Fig. 6B, the sample droplets 14 could be vaporized even if the length of the second pipe line section 13 was about 150 mm at a heating temperature of 300°C. This is an effect similar to that obtained when the inner diameter of the second pipe line section 13 not provided with the partition wall 39 was set to about 10 mm. In other words, by providing the partition wall 39, an effect similar to that obtained when the inner diameter of the second pipe line section 13 was halved was obtained.

[0099] The shape of the dividing wall 39 is not limited to the shapes shown in FIGS. 6A and 6B, and may have any shape as long as the substantial inner diameter of the second pipe portion 13 can be reduced.

[0100] FIG. 6C is a diagram showing the BB cross section of FIG. 6A. The partition wall 39 extends in the direction of the flow 17 of the transport gas 8, but is not provided near the ultrasonic sample liquid atomization unit 5 as shown in FIG. 6A and FIG. 6C. This is to prevent the sample droplets 14 sprayed from the ultrasonic sample liquid atomization unit 5 from adhering to the partition wall 39. The partition wall 39 is heated to a high temperature, similar to the wall surface of the second pipe section 13. If the sample droplets 14 adhere to the partition wall 39, they may be decomposed and disappear due to the high temperature. As shown in FIG. 6C, if the partition wall 39 is not provided near the ultrasonic sample liquid atomization unit 5, most of the sample droplets 14 sprayed from the ultrasonic sample liquid atomization unit 5 and carried by the flow 17 of the transport gas 8 may be transported inside the second pipe section 13 without coming into contact with the partition wall 39.

[0101] In order to efficiently heat the transport gas 8 that transports the sample droplets 14, it is desirable that the second pipe line portion 13 and the partition wall 39 are made of a material with high thermal conductivity, such as a metal.

[0102] <Charge applying section> 1, the following will explain the charge imparting unit 18. The charge imparting unit 18 imparts a positive or negative charge to the sample components contained in the sample droplets 14, which are the atomized sample liquid 7, to ionize them.

[0103] The charge imparting unit 18 is provided at the other end of the second pipe line section 13 (the end opposite to the end connected to the first pipe line section 10), i.e., the downstream side of the second pipe line section 13, and connected to the second pipe line section 13. The charge imparting unit 18 imparts an electric charge to the sample components contained in the sample droplets 14 vaporized by the second pipe line section 13, and ionizes the sample components. An exhaust pipe 25 is connected to the downstream side of the charge imparting unit 18. FIG. 1 shows a charge imparting unit 18 that utilizes corona discharge as an example.

[0104] Moreover, the charge applying section 18 can also be provided at one end of the second duct section 13 connected to the first duct section 10 by being connected to the second duct section 13 .

[0105] 1 includes a tubular member, a thin discharge wire 19 having a diameter of about several tens of μm, and a counter electrode 20. The counter electrode 20 is made of a conductive member disposed on a part of the wall surface of the tubular member, and is electrically insulated from the second pipe section 13 and the exhaust pipe 25.

[0106] A high voltage power supply 21 that applies a high voltage is connected to the discharge wire 19. When a high voltage is applied to the discharge wire 19, a corona discharge occurs due to a potential difference with the counter electrode 20. When a negative high voltage is applied to the discharge wire 19, electrons generated by the corona discharge flow toward the counter electrode 20, and a negative charge can be imparted to the sample components contained in the sample droplets 14 transported from the second pipeline section 13 by the transport gas 8. When a positive high voltage is applied to the discharge wire 19, positive ions generated by the corona discharge flow toward the counter electrode 20, and a positive charge can be imparted to the sample components contained in the sample droplets 14 transported from the second pipeline section 13 by the transport gas 8. The charge imparting section 18 can impart a charge of a polarity that matches the analysis method and the type of sample components to the sample components by switching the polarity of the voltage applied to the discharge wire 19.

[0107] The sample components that have been ionized by being charged are attracted toward the counter electrode 20 by the force of the electric field generated between the discharge wire 19 and the counter electrode 20. The counter electrode 20 is connected to the analytical section 24 and has a small hole that opens into the analytical section 24. Some of the ionized sample components are introduced into the analytical section 24 through the small hole provided in the counter electrode 20. In FIG. 1, the flow of the ionized sample components into the analytical section 24 is indicated by arrows 23.

[0108] The analysis section 24 introduces the ionized sample components into a vacuum and separates the sample components according to their mass-to-charge ratios using, for example, mass spectrometry, and identifies the components.

[0109] A control power supply 22 capable of adjusting the potential of the counter electrode 20 may be connected to the counter electrode 20. The control power supply 22 can make the potential of the counter electrode 20 slightly higher than the internal voltage of the analysis section 24, thereby strengthening the electric field strength toward the analysis section 24, and the ionized sample components can easily enter the analysis section 24 through the small holes of the counter electrode 20. However, if the potential of the counter electrode 20 is made too high, the electric field from the discharge wire 19 toward the counter electrode 20 becomes weak, and the amount of sample components introduced into the analysis section 24 decreases. In this embodiment, the charge applying section 18 is provided with a control power supply 22 capable of adjusting the potential of the counter electrode 20, and it is possible to adjust the potential of the counter electrode 20 so that the ionized sample components are introduced into the analysis section 24 more efficiently.

[0110] An exhaust pipe 25 is provided downstream of the charge applying unit 18. The exhaust pipe 25 exhausts the transport gas 8 after the ionized sample components are introduced into the analysis unit 24. In Fig. 1, the flow of the transport gas 8 exhausted by the exhaust pipe 25 is indicated by arrows 26.

[0111] 7A to 7C are diagrams showing configuration examples of the charge supplying section 18. The charge supplying section 18 may have any configuration, and may have, for example, the configurations shown in Figures 7A to 7C.

[0112] Fig. 7A shows a charge imparting unit 18 having a configuration similar to that of the charge imparting unit 18 shown in Fig. 1. The charge imparting unit 18 shown in Fig. 7A includes a discharge wire 19, and imparts an electric charge to the sample components contained in the vaporized sample droplets 14 by utilizing corona discharge.

[0113] 7B shows the charge applying unit 18 including a needle-shaped member 40. The needle-shaped member 40 is a needle electrode (discharge electrode). The charge applying unit 18 shown in FIG. 7B generates a corona discharge using the needle-shaped member 40 to apply a charge to the sample components contained in the vaporized sample droplets 14.

[0114] 7C shows a charge applying unit 18 including an ion emitting device 41 that utilizes plasma or the like. The charge applying unit 18 shown in FIG. 7C uses the ion emitting device 41 to apply an electric charge to the sample components contained in the vaporized sample droplets 14.

[0115] The charge imparting unit 18 described above heats and vaporizes the atomized sample droplets 14, and imparts an electric charge to the sample components contained in the heated and vaporized sample droplets 14. The charge imparting unit 18 can also impart an electric charge to the sample components when the sample liquid 7 is atomized.

[0116] 8 is a diagram showing the configuration of the charge imparting unit 18 that imparts an electric charge to the sample components contained in the sample droplets 14 when the sample liquid 7 is atomized. The charge imparting unit 18 includes a high-voltage DC power supply circuit 42. The high-voltage DC power supply circuit 42 is a power supply circuit that supplies a high voltage to the vibration surface 1 of the ultrasonic sample liquid atomization unit 5.

[0117] The high-voltage DC power supply circuit 42 is connected to the ultrasonic sample liquid atomization unit 5 and applies a high voltage to the signal generated by the drive circuit 6, thereby raising the overall AC signal for driving the ultrasonic sample liquid atomization unit 5 to a high voltage. The drive circuit 6 ultrasonically drives the piezoelectric element in a state in which a high voltage is applied by the high-voltage DC power supply circuit 42. The vibration surface 1 of the ultrasonic sample liquid atomization unit 5 ultrasonically vibrates in a state in which a high voltage is supplied by the high-voltage DC power supply circuit 42.

[0118] Furthermore, the atomization unit holding member 11 that holds the ultrasonic sample liquid atomization unit 5 has an electrical insulating structure so that the ultrasonic sample liquid atomization unit 5 can be electrically isolated from the wall surface of the first pipeline section 10. This electrical insulating structure can be made of an insulating material such as insulating elastic rubber.

[0119] The sample droplets 14 sprayed and atomized from the ultrasonic sample liquid atomization unit 5 are given an electric charge due to a potential difference generated between the vibration surface 1 to which a high voltage is supplied and the wall surface of the second duct section 13. The charged sample droplets 14 are attracted to the wall surface of the second duct section 13 by the electric field.

[0120] 8, this embodiment may also have a configuration in which an AC voltage application circuit 43 is connected to the wall surface of the second pipe line section 13. The AC voltage application circuit 43 applies an AC voltage having an offset voltage to the wall surface of the second pipe line section 13. When the AC voltage application circuit 43 applies an appropriate offset voltage and an AC voltage to the wall surface of the second pipe line section 13, even if the sample droplets 14 are charged, they are not attracted to the wall surface of the second pipe line section 13, but are transported downstream through the second pipe line section 13 by the transport gas 8 and vaporized.

[0121] As described above, the sample liquid atomization device according to this embodiment includes a sample liquid atomization section, a heating vaporization section, and a charge applying section, and can constitute a simple and very stable ion source for the analysis section 24. The analysis device according to this embodiment includes this sample liquid atomization device, and can be provided with a stable ion source.

[0122] The present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to an embodiment having all of the configurations described. It is also possible to replace a part of the configuration of one embodiment with the configuration of another embodiment. It is also possible to add the configuration of another embodiment to the configuration of one embodiment. It is also possible to delete a part of the configuration of each embodiment, or to add or replace another configuration. [Explanation of symbols]

[0123] 1...vibration surface, 2...vibration member, 3...vibration section, 4...connection section, 5...ultrasonic sample liquid atomization unit, 6...drive circuit, 7...sample liquid, 7a...piping, 8...transport gas, 8a...piping, 9...rectification section, 10...first pipe section, 11...atomization unit holding member, 12...insulating connection member, 13...second pipe section, 14...sample droplets, 15...heating section, 16...power supply, 17...flow of transport gas, 18...charge application section, 19...discharge wire, 20...counter electrode, 21...high voltage power supply, 22...control power supply, 23...sample composition Arrow indicating flow of gas, 24...analysis section, 25...exhaust pipe, 26...arrow indicating flow of exhausted transport gas, 27...mesh thin plate, 28...hole, 29a, 29b...elastic body, 30...anti-pullout section, 31...direction of ultrasonic vibration, 32...elastic rubber, 33...rod-shaped member, 34...plate-shaped member, 35...retaining member, 36...groove, 37...retaining member, 38...plate-shaped member, 39...dividing wall, 40...needle-shaped member, 41...ion emission device, 42...high-voltage DC power supply circuit, 43...AC voltage application circuit, 44...holding frame.

Claims

1. an ultrasonic sample liquid atomization unit including a vibration unit that generates ultrasonic vibrations, a vibration surface that is vibrated by the vibration unit, a vibration member that includes the vibration surface, and a pipe that supplies a sample liquid to the vibration surface, the ultrasonic sample liquid atomization unit atomizing the sample liquid supplied to the vibration surface by ultrasonic vibration of the vibration surface; A first pipe portion which is a tubular member; Equipped with the first duct portion extends in a direction of ultrasonic vibration of the vibration surface, the ultrasonic sample liquid atomization unit is provided inside the first pipeline portion and is supported by a holding member on the first pipeline portion; The inside of the first pipeline portion is configured so that a gas flows around the ultrasonic sample liquid atomization unit. A sample liquid atomization device characterized by:

2. An ultrasonic sample liquid atomization unit comprising: a vibration section which generates ultrasonic vibrations; a vibration surface which is vibrated by the vibration section; a vibration member which is provided with the vibration surface; and a pipe which supplies a sample liquid to the vibration surface, the sample liquid supplied to the vibration surface being atomized by the ultrasonic vibration of the vibration surface; A first pipe portion which is a tubular member; Equipped with the first duct portion extends in a direction of ultrasonic vibration of the vibration surface, the ultrasonic sample liquid atomization unit is provided inside the first pipeline portion and is supported by a holding member on the first pipeline portion; The holding member is configured to connect the vibration member and the first pipeline portion and to support the ultrasonic sample liquid atomization unit so that ultrasonic vibration of the ultrasonic sample liquid atomization unit is not transmitted to the first pipeline portion. A sample liquid atomization device characterized by:

3. The holding member includes an elastic member having a lower rigidity than the vibrating member. The sample liquid atomizing device according to claim 2 .

4. The holding member includes a member that is slidable relative to a groove provided in the vibration member. The sample liquid atomizing device according to claim 2 .

5. the vibration member includes the vibration surface at one end and the excitation portion between the one end and the other end, The holding member is connected to the vibration member between the other end and the vibration unit. The sample liquid atomizing device according to claim 1 .

6. the first duct portion includes a pipe through which the gas flows inside the first duct portion, One or both of the ultrasonic sample liquid atomization unit and the holding member are made of metal. The sample liquid atomizing device according to claim 1 .

7. the first duct portion includes a pipe through which the gas flows inside the first duct portion, One or both of the ultrasonic sample liquid atomization unit and the holding member have an uneven surface. The sample liquid atomizing device according to claim 1 .

8. The vibration surface includes a plate-like member having one or more holes on a surface thereof, The piping supplies the sample liquid between the vibration surface and the plate-like member. The sample liquid atomizing device according to claim 1 .

9. An ultrasonic sample liquid atomization unit comprising: a vibration section which emits ultrasonic vibrations; a vibration surface which is vibrated by the vibration section; a vibration member which has the vibration surface; and a pipe which supplies a sample liquid to the vibration surface, the sample liquid supplied to the vibration surface being atomized by the ultrasonic vibration of the vibration surface; A first pipe portion which is a tubular member; a second pipe portion which is a tubular member; Equipped with the first duct portion extends in a direction of ultrasonic vibration of the vibration surface, the ultrasonic sample liquid atomization unit is provided inside the first pipeline portion and is supported by a holding member on the first pipeline portion; the second pipeline portion has one end connected to the first pipeline portion via a heat insulating member, and includes a heating portion that heats a wall surface of the second pipeline portion. A sample liquid atomization device characterized by:

10. a charge applying unit that applies a positive or negative charge to a sample component contained in the atomized sample liquid, at the one end or the other end of the second pipe section; The sample liquid atomizing device according to claim 9.

11. A power supply circuit is provided to supply a voltage to the vibration surface. The sample liquid atomizing device according to claim 1 .

12. An analytical device comprising the sample liquid atomization device according to any one of claims 1 to 11.

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