Connection part of tube at which liquid leakage control member is provided, ICP emission spectral analyzer, and method for operating ICP emission spectral analyzer

Abstract

To provide means for preventing a risk where, when a liquid sample is scattered and leaked inside a sample introduction part of an ICP emission spectral analyzer, the scattered liquid sample is adhered on an operator to cause a chemical injury, the operator have their hands or fingers caught in a movable part of a pump to get injured, and the liquid sample is adhered on the pump to cause malfunction.SOLUTION: A connection part of a tube has: a first tube having a predefined hardness and inner diameter; and a second tube harder than the first tube, having an outer diameter than the inner diameter of the first tube, and capable of being fitted into the first tube. A fitting portion is constituted by the second tube being fitted into the first tube. The fitting portion constitutes a connection part for sending liquid. The connection part is included in a splash-prevention tube having an inner diameter larger than an outer diameter of the first tube. The connection part of the tube is provided with a liquid leakage control member in which, when a sending pressure of the liquid exceeds a predefined value causing detachment of the fitting portion and the liquid is leaked outward from the connection part, the splash-prevention tube serves as the liquid leakage control member to control splash of the liquid leaked from the connection part.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a connection portion of a tube provided with a liquid leakage control member, an ICP emission spectroscopic analyzer, and a method for operating the ICP emission spectroscopic analyzer.

Background Art

[0002] In various manufacturing apparatuses and analytical apparatuses, in many cases, a predetermined pressure is applied to a liquid having corrosiveness or harmfulness to the human body, and the liquid is sent through a liquid feeding system including a tube. If these liquid feedings are carried out smoothly, there is no problem, but there may be a case where a blockage occurs in the liquid feeding system for some reason. In such a case, if the liquid feeding device (for example, a liquid feeding pump) does not stop, the pressure of the liquid in the liquid feeding system upstream of the blockage portion will increase, and a portion vulnerable to the pressure in the liquid feeding system will be damaged, ruptured, etc., and the liquid will leak while scattering outside the liquid feeding system.

[0003] The damage, rupture, etc. of the inside of the liquid feeding system and the leakage of the liquid while scattering outside the liquid feeding system may cause damage, rupture, etc. of expensive parts and injury to the human body, which is a situation that must be avoided.

[0004] In order to avoid the above situation, it is conceivable to provide a mechanism for monitoring the pressure of the liquid in the liquid feeding system and stopping the liquid feeding device when the pressure of the liquid in the liquid feeding system increases for some reason and exceeds a predetermined value. However, when the liquid feeding system is small-scale or simple, it may not always be accurate to provide a mechanism for monitoring the pressure of the liquid and stopping the liquid feeding device when the pressure of the liquid in the liquid feeding system increases and exceeds a predetermined value.

[0005] As an example of such a case where the liquid to be fed may be corrosive or harmful to the human body and the liquid feeding system is small-scale or simple, there is a liquid feeding system in an ICP emission spectroscopic analyzer (which may be referred to as an "ICP device" in the present invention), which is one of the analyzers for performing elemental analysis using high-frequency inductively coupled plasma (ICP). Hereinafter, the present invention will be described with reference to an ICP device as an example.

[0006] An ICP device is a device that performs elemental analysis by spectroscopically analyzing the light emitted by an element using the thermal energy of a plasma, such as a prism, and measuring the wavelength and intensity of the light. For this purpose, in an ICP device, it is necessary to atomize a liquid sample and introduce it into the plasma. Therefore, the sample introduction section in the ICP device is provided with a peristaltic pump as a pump for sample introduction, a nebulizer for atomizing the liquid sample as a subsequent process, and a cyclone chamber for collecting the liquid sample, and these are connected by a liquid delivery tube. As a document related to the sample introduction section, for example, there is Patent Document 1.

Prior Art Document

Patent Document

[0007] Japanese Patent Application Laid-Open No. 2006-66312

Summary of the Invention

Problems to be Solved by the Invention

[0008] When performing an analysis operation using an ICP device, liquid is fed to the nebulizer through a connection point between a flexible liquid delivery tube (which may be referred to as the "first tube" in the present invention) that cooperates with the peristaltic pump in the liquid delivery series and a nebulizer introduction tube that is a semi-rigid tube connected to the nebulizer (which may be referred to as the "second tube" in the present invention).

[0009] At this time, at the connection point, the second tube, which is a semi-rigid tube connected to the nebulizer, fits into the flexible first tube that cooperates with the peristaltic pump to form a fitting portion, and the connection point of the first and second tubes is formed by the fitting portion, so that liquid is fed to the nebulizer without leaking outside the two tubes.

[0010] However, depending on the state of the solution which is a liquid sample, fine particles may be generated in the liquid, etc., and the nebulizer may become clogged. When the nebulizer becomes clogged, the spraying state of the liquid sample deteriorates, and liquid pressure may be applied to the connection part. When the liquid pressure rises and exceeds a predetermined value, the fitting parts of the first and second tubes come off, and the liquid sample leaks while scattering from the first tube on the liquid feeding side. Here, the liquid sample is often a highly corrosive liquid with strong acidity such as hydrochloric acid solution, sulfuric acid solution, nitric acid solution, hydrofluoric acid solution, etc.

[0011] When the liquid sample leaks while scattering, the scattered liquid sample may adhere to the operator and cause chemical burns, or the operator may be panicked and try to respond, and fingers or the like may be caught in the moving part of the peristaltic pump. Also, when the liquid sample adheres during the high-speed rotation of the peristaltic pump, the adhesion range may spread and corrode, and the rotating part may become fixed and malfunction. Furthermore, the liquid sample also leaks while scattering around the ICP device.

[0012] In order to avoid such a situation, it is also conceivable to firmly connect the two tubes at the connection part of the first and second tubes. However, if the first and second tubes are firmly connected, then the liquid pressure will be applied to the nebulizer and the peristaltic pump this time, and it is conceivable that the expensive glass nebulizer will be damaged.

[0013] On the other hand, it is also conceivable to provide a mechanism for monitoring the liquid pressure of the liquid sample and stopping the peristaltic pump when the liquid pressure in the liquid feeding system rises and exceeds a predetermined value. However, since the liquid feeding system in the ICP device is small-scale and simple, it was considered that it was not appropriate to provide a mechanism for monitoring the liquid pressure in the liquid feeding system and stopping the liquid feeding device when the liquid pressure exceeds a predetermined value.

Means for Solving the Problem

[0014] To solve the above problems, the present inventors conducted research. Then, even when a hydraulic pressure equal to or higher than a predetermined value is applied to the connection portion of the first and second tubes and the fitting portions of the first and second tubes come off, a liquid splash prevention tube that can enclose the connection portion of these first and second tubes within the tube is prepared. Then, the connection portion of the first and second tubes is enclosed in the liquid splash prevention tube in advance, and even when the fitting portions of the first and second tubes come off, while maintaining the connection of the first and second tubes, the leaked liquid sample can be leaked without scattering from the gap between the second tube and the liquid splash prevention tube.

[0015] Furthermore, the present inventors conducted research, and even when a hydraulic pressure equal to or higher than a predetermined value is applied to the connection portion of the first and second tubes and the fitting portions of the first and second tubes come off, a liquid splash prevention storage container that liquid-tightly stores the connection portion of these first and second tubes inside, and a drain member for sending the liquid leaked to the outside from the connection portion to a desired place is provided in the liquid splash prevention storage container. By providing a liquid leakage control member, the inventors also conceived that the leaked liquid sample can be sent to a desired place without scattering, and thus completed the present invention.

[0016] That is, a first invention for solving the above problems is a first tube having a predetermined hardness and inner diameter, a second tube that is harder than the first tube, has an outer diameter equal to or larger than the inner diameter of the first tube, and can be fitted into the first tube, the second tube is fitted into the first tube to form a fitting portion, the fitting portion constitutes a connection portion of the first and second tubes for sending liquid through the first and second tubes, a connection portion of the tubes, wherein a liquid leakage control member is provided at the connection portion to control the fitting portion of the second tube to the first tube from coming off and liquid from leaking outside the connection portion when the liquid feed pressure exceeds a predetermined value. A second invention is The liquid leakage control member is a liquid splash prevention tube having an inner diameter equal to or greater than the outer diameter of the first tube, the liquid splash prevention tube encloses the connection point within the liquid splash prevention tube, when the liquid feed pressure of the liquid exceeds a predetermined value, the inserted portion comes off, and when the liquid leaks outside from the connection point, the liquid splash prevention tube serves as a liquid leakage control member to control the scattering of the liquid leaked from the connection point. This is the connection point of the tube provided with the liquid leakage control member according to the first invention. The third invention is, the liquid splash prevention tube encloses, within the liquid splash prevention tube, a first tube having a length of 3 times or more and 5 times or less the outer diameter of the first tube extending from the central position of the connection point in the longitudinal direction of the first tube, and a second tube having a length of 10 times or more and 20 times or less the outer diameter of the second tube extending from the central position of the connection point in the longitudinal direction of the second tube. This is the connection point of the tube provided with the liquid leakage control member according to the second invention. The fourth invention is, the liquid leakage control member is a liquid splash prevention storage container that liquid-tightly houses the connection point inside, the liquid splash prevention storage container is provided with a drain member for feeding the liquid leaked outside from the connection point to a desired location. This is the connection point of the tube provided with the liquid leakage control member according to the first invention. The fifth invention is, the liquid splash prevention storage container houses, within the liquid splash prevention storage container, a first tube having a length of 5 times or more and 10 times or less the outer diameter of the first tube extending from the central position of the connection point in the longitudinal direction of the first tube, and a second tube having a length of 10 times or more and 20 times or less the outer diameter of the second tube extending from the central position of the connection point in the longitudinal direction of the second tube. This is the connection point of the tube provided with the liquid leakage control member according to the fourth invention. The sixth invention is, An ICP emission spectroscopic analyzer, characterized by having a connection point of a tube provided with the liquid leakage control member according to any one of the first to fifth inventions. The seventh invention is An operating method of an ICP emission spectroscopic analyzer, characterized by providing a connection point of a tube provided with the liquid leakage control member according to any one of the first to fifth inventions to the ICP emission spectroscopic analyzer and feeding a liquid to a nebulizer of the ICP emission spectroscopic analyzer.

Effect of the Invention

[0017] A liquid splash prevention tube is provided at the fitting portion of a first tube having a predetermined hardness and inner diameter and a second tube that is harder than the first tube, has an outer diameter equal to or larger than the inner diameter of the first tube, and can be fitted into the first tube. By enclosing the fitting portions of the first and second tubes in the liquid splash prevention tube or storing them in the liquid splash prevention storage container, even when the fitting portion of the tube comes off and a liquid sample leaks, the liquid does not scatter, ensuring work safety, avoiding adhesion to peripheral devices such as pumps, and preventing device failures.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0019] Regarding the embodiments for implementing the present invention, taking the case of applying the present invention to an ICP device as an example, (1) an overview of the ICP device, (2) the first tube and the second tube, (3) the increase in hydraulic pressure and the leakage and scattering of liquid, and (4) the liquid leakage control member will be described in this order.

[0020] (1) An overview of the ICP device, The sample introduction part of the ICP device is equipped with a peristaltic pump, a nebulizer, and a cyclone chamber for sample introduction. The ICP device and the sample introduction part will be described with reference to the drawings. Note that in different drawings, the parts with the same numbers are the same parts. Figure 1 is an external view of an example of the ICP device. In Figure 1, reference numeral 1 is the main body of the ICP device, reference numeral 2 is the sample introduction part of the ICP device, reference numeral 4 is the operation PC of the ICP device, reference numeral 5 is an autosampler, and reference numeral 6 is a waste liquid container. Reference numeral 42 is a drain tube that discharges the waste liquid from the leakage - corresponding drain hole provided in the device body tray of the ICP device described later to the waste liquid container 6.

[0021] Figure 2 is an enlarged external view of the sample introduction part of the ICP device. In Figure 2, reference numeral 10 is a peristaltic pump (which may be described as "pump" in the present invention), reference numeral 20 is a nebulizer, reference numeral 30 is a cyclone chamber, reference numeral 40 is the device body tray of the ICP device, and reference numeral 50 is an Ar humidifier for supplying carrier gas (humidified Ar gas) to the nebulizer.

[0022] The pump 10 sends the solution from the sample container to the nebulizer and at the same time discharges the waste liquid coming out of the cyclone chamber (which may also be described as a spray chamber). There are various types of pumps, but a peristaltic pump is often used.

[0023] The nebulizer 20 is a spraying device, which is connected to the cyclone chamber 30, mixes the solution sent by the pump 10 with the carrier gas, and sprays the solution into the cyclone chamber 30.

[0024] The cyclone chamber 30 is a gas-liquid separation device, which introduces a part of the solution mixed and sprayed with the carrier gas by the nebulizer 20 into the plasma, and allows the sprayed solution not introduced into the plasma to fall to the lower part of the cyclone chamber 30. The fallen solution is discharged so as not to stay.

[0025] (2) Tube for feeding the solution Next, the tube for feeding the solution will be described. From the solution inlet to the pump part inlet, the solution introduction tube 12 is used. Then, the solution introduction tube 12 and the liquid feeding tube 11 (described as the "first tube" in the means for solving the problem section) are connected at the first connection point 14, and after passing through the pump 10, the liquid feeding tube 11 and the nebulizer introduction tube 13 (described as the "second tube" in the means for solving the problem section) are connected at the second connection point 15. After that, the nebulizer introduction tube 13 is connected to the nebulizer 20.

[0026] After passing through the cyclone chamber 30, the first discharge tube 35 is connected from the lower part of the cyclone chamber 30. Then, at the third connection point 38 at its tip, it is connected from the first discharge tube 35 to the second discharge tube 36, and after passing through the pump 10, at the fourth connection point 39, the second discharge tube 36 and the third discharge tube 37 are connected. In addition, in FIG. 2, the solution inlet of the solution introduction tube 12 is immersed in the pure water in the pure water container 151.

[0027] Here, the liquid feeding tube 11 passing through the pump 10 is a flexible tube. On the other hand, the solution introduction tube 12 and the nebulizer introduction tube 13 are semi-rigid tubes.

[0028] In the present invention, the flexible tube means, for example, a tube that can perform continuous liquid feeding by rotating while the roller of the peristaltic pump crushes the flexible tube when the flexible tube passes through the peristaltic pump. On the other hand, in the present invention, the semi-rigid tube means, for example, a tube that can be easily bent but is harder than the flexible tube.

[0029] Examples of the tube material include silicone rubber, fluororesin, fluororubber, polyurethane resin, nylon resin, polyolefin resin, etc. Silicon rubber (hardness 50° to 70°) is often used for the liquid feeding tube 11 and the liquid splash prevention tube described later, and fluororubber (hardness 60° to 80°) is often used for the solution introduction tube 12 and the nebulizer introduction tube 13. It is preferable that the hardness difference between the liquid feeding tube 11 and the liquid splash prevention tube described later and the nebulizer introduction tube 13 is 5° to 10° higher for the nebulizer introduction tube 13.

[0030] Also, the second discharge tube 36 passing through the pump 10 is a flexible tube. On the other hand, the first discharge tube 35 is a dedicated semi-rigid tube with slightly smaller inner and outer diameters than the second discharge tube 36, and the third discharge tube 37 is a semi-rigid tube with slightly larger inner and outer diameters than the second discharge tube 36 and is connected to the waste liquid container 6. Silicon rubber (hardness 50° to 70°) is often used for flexible tubes, and fluororubber (hardness 60° to 80°) is often used for semi-rigid tubes.

[0031] At the first to third connection points, the semi-rigid tube is inserted into the flexible tube, whereby the two tubes are connected. At the fourth connection point, the second discharge tube 36 and the third discharge tube 37 are connected by a dedicated pipe joint having an outer diameter adapted to the inner diameter of each tube.

[0032] On the other hand, in case there is a solution leakage inside the sample introduction part of the ICP device, a drain tube 42 is provided from a leakage countermeasure drain hole 41 provided in the device main body tray 40 to a waste liquid container 6 provided below the ICP device 1.

[0033] The facilities such as the above-described nebulizer 20, cyclone chamber 30, liquid feeding tube 11, solution introduction tube 12, nebulizer introduction tube 13, first discharge tube 35, second discharge tube 36, and third discharge tube 37 are contaminated by sample introduction, so they are disassembled and cleaned or replaced as necessary, and flow rate adjustment and the like are also performed. Therefore, due to maintenance reasons, these facilities are installed naked inside the sample introduction part 2 of the ICP device. During measurement, the pump 10 rotates at high speed to send the solution into the nebulizer 20, spray it into the cyclone chamber 30, and introduce it into the plasma.

[0034] At this time, it is preferable that the solution introduction tube 12, the liquid feeding tube 11, and the nebulizer introduction tube 13 are as short as possible. This is to reduce the solution remaining and wasted in these tubes during the replacement of the liquid sample, and to reduce the burden of the cleaning operation for removing the remaining solution. In particular, when the solution is a rare sample, or when measurement is performed while sequentially replacing various solutions using, for example, an autosampler 5, it is considered important to reduce the amount of solution remaining in the tubes. As a result, along with the shortening of the solution introduction tube 12, the liquid feeding tube 11, and the nebulizer introduction tube 13, the second connection point 15 is at a high position inside the sample introduction part 2 and is located above the pump 10.

[0035] (3) Increase in liquid pressure and leakage / scattering of liquid However, if there are fine particles or dust in the solution, or if the solution is in a state where crystals or the like are likely to form, the nebulizer 20 is likely to become clogged. When the nebulizer 20 becomes clogged, the spraying state of the solution deteriorates, hydraulic pressure is applied to the second connection point 15 between the liquid feeding tube 11 and the nebulizer introduction tube 13, and the liquid feeding tube 11 and the nebulizer introduction tube 13 may become detached, causing the solution to scatter and leak. Here, the solution is often a highly acidic and corrosive liquid such as a hydrochloric acid solution, a sulfuric acid solution, a nitric acid solution, or a hydrofluoric acid solution.

[0036] When the solution scatters and leaks at a high position inside the sample introduction unit 2 above the pump 10, the scattered solution may adhere to the operator, causing chemical burns, or the operator may be panicked and try to respond, getting a finger or the like caught in the moving part of the pump 10. If the nebulizer 20 or the cyclone chamber 30 is made of quartz, there is a risk that the operator's hand may hit and break them, causing injury. Also, since the second connection point 15 is in the vicinity above the pump 10, if the solution adheres during the high-speed rotation of the pump 10, the adhesion range may spread and cause corrosion, and the rotating part may become fixed and malfunction. Furthermore, when such a situation occurs during unattended nighttime measurement or the like using the autosampler 5, the solution will also scatter and leak around the ICP device 1.

[0037] In the above-described situation, as shown in FIG. 3, which is a schematic cross-sectional view of the second connection point, a semi-rigid nebulizer introduction tube 13 having an outer diameter Mφ (where Mφ > lφ) (for example, an outer diameter of 1.3φ) is fitted into a liquid feeding tube 11 made of a soft and stretchable material having an inner diameter lφ and an outer diameter Lφ (for example, an inner diameter of 1.03φ and an outer diameter of 2.8φ), forming the second connection point 15 for connection. At this time, due to the difference in hardness of the materials of the liquid feeding tube 11 and the nebulizer introduction tube 13, the inner diameter of the stretchable liquid feeding tube 11 expands from lφ to l´φ (where lφ < l´φ), and the outer diameter expands from Lφ to L´φ (where Lφ < L´φ). Then, the outer diameter Mφ of the nebulizer introduction tube 13 and the inner diameter l´φ of the expanded liquid feeding tube 11 are in a state where Mφ ≒ l´φ.

[0038] In this state, when the nebulizer 20 becomes clogged, the hydraulic pressure in the liquid delivery tube 11 and the nebulizer introduction tube 13 increases, and the fitting part comes off at the second connection point 15. Therefore, it may be considered that the liquid delivery tube 11 and the nebulizer introduction tube 13 should be firmly engaged at the second connection point 15. However, if the liquid delivery tube 11 and the nebulizer introduction tube 13 are firmly connected so as not to come off, the increased hydraulic pressure due to the clogging of the nebulizer 20 will be applied to the nebulizer 20, and it is conceivable that the glass-made and expensive nebulizer 20 will be damaged.

[0039] In order to avoid damage to the nebulizer 20, it is considered preferable to use the second connection point 15 as a safety valve for releasing the hydraulic pressure. On the other hand, in this case, when the fitting part comes off at the second connection point 15 between the liquid delivery tube 11 and the nebulizer introduction tube 13, it is considered that scattering of the solution accompanying the swinging of the liquid delivery tube 11, entrainment of the liquid delivery tube 11 into the pump 10, etc. will occur.

[0040] If such a situation occurs, there is a risk that the scattered liquid sample adheres to the operator and causes chemical burns, or the operator's finger or the like is caught in the moving part of the pump while trying to respond hurriedly. If the nebulizer or the cyclone chamber is made of quartz, there is also a risk that the operator's hand hits and breaks, causing injury. Also, when a liquid sample adheres during high-speed rotation of the pump, the adhesion range may spread and corrode, and the rotating part may become fixed and malfunction. Furthermore, the liquid sample will also scatter and leak around the ICP device.

[0041] (4) Liquid Leakage Control Member Here, the inventors have come up with the idea that while using the second connection point 15 as a safety valve for releasing the hydraulic pressure, it is sufficient to maintain the mechanical connection between the liquid delivery tube 11 and the nebulizer introduction tube 13 even if they come off, and have come up with the liquid leakage control member. In the liquid leakage control member according to the present invention, there are a liquid splash prevention tube and a liquid splash prevention storage container. Hereinafter, (I) the liquid splash prevention tube and (II) the liquid splash prevention storage container will be described in this order.

[0042] (I) Liquid splash prevention tube FIG. 4 is a schematic cross-sectional view of a second connection portion 15(2) provided with a splash prevention tube that encloses a second connection portion 15 within the tube of the liquid splash prevention tube 17. Note that the liquid splash prevention tube 17 is an example of an embodiment of a member described as a "liquid leakage control member" in the means for solving the problem section.

[0043] At the second connection portion 15(2) provided with the liquid splash prevention tube 17 having an inner diameter of nφ (where Lφ ≒ nφ) (for example, an inner diameter of 2.8φ), as the outer diameter of the liquid supply tube 11 expands from Lφ to L'φ, the inner diameter of the liquid splash prevention tube 17 also expands from nφ to n'φ (where nφ < n'φ). As a result, L'φ ≒ n'φ, and the liquid supply tube 11 of the second connection portion 15 having the above-described expanded outer diameter L'φ is enclosed within the tube of the liquid splash prevention tube 17 without a gap.

[0044] And because the second connection portion 15(2) is enclosed within the tube of the liquid splash prevention tube 17, even if the inserted portions of the liquid supply tube 11 and the nebulizer introduction tube 13 come off due to an increase in liquid pressure, the terminal of the nebulizer introduction tube 13 having an outer diameter of Mφ is secured within the liquid splash prevention tube 17 having an inner diameter of nφ (where Mφ < nφ), thereby ensuring the mechanical connection between the liquid supply tube 11 and the nebulizer introduction tube 13. From the above viewpoints, the liquid splash prevention tube 17 is preferably a silicone rubber tube (hardness 50° to 70°).

[0045] At this time, the length of the overlapping portion between the liquid splash prevention tube 17 and the liquid delivery tube 11, and the length of the overlapping portion between the liquid splash prevention tube 17 and the nebulizer introduction tube 13 only need to be such that when the liquid delivery tube 11 and the nebulizer introduction tube 13 become detached, the terminal of the nebulizer introduction tube 13 is included within the liquid splash prevention tube 17, thereby maintaining the mechanical connection between the liquid delivery tube 11 and the nebulizer introduction tube 13. However, if the insertion portion of the nebulizer introduction tube 13 into the liquid delivery tube 11 is too long, the operation of inserting the nebulizer introduction tube 13 into the liquid delivery tube 11 will become difficult.

[0046] Therefore, specifically, in the liquid splash prevention tube 17, the length A of the inclusion portion in the longitudinal direction of the liquid delivery tube 11 from the central position C of the second connection portion 15 only needs to be 3 times or more the outer diameter of the liquid delivery tube 11, and preferably 5 times or less. On the other hand, the length B of the inclusion portion in the longitudinal direction of the nebulizer introduction tube 13 from the central position C of the second connection portion 15 only needs to be 10 times or more the outer diameter of the nebulizer introduction tube 13, and preferably 20 times or less.

[0047] In the present invention, the central position of the connection portion refers to the central position between the end of the liquid delivery tube 11 constituting the insertion portion and the end of the nebulizer introduction tube 13. Also, as dimensions related to the outer diameter of the tube, there are dimensions related to the radial direction of the tube and dimensions related to the longitudinal direction of the tube. In the present invention, the dimensions related to the longitudinal direction of the tube are described as "the length in the longitudinal direction of the tube".

[0048] And, "from the central position C of the second connection portion 15 in the longitudinal direction of the liquid delivery tube" means in the direction from the central position C of the second connection portion 15 toward the pump 10, and "from the central position C of the second connection portion 15 in the longitudinal direction of the nebulizer introduction tube" means in the direction from the central position C of the second connection portion 15 toward the nebulizer 20.

[0049] That is, the liquid splash prevention tube 17 may include, within the liquid splash prevention tube, the liquid delivery tube 11 having a length of 3 to 5 times the outer diameter of the liquid delivery tube 11 extending in the longitudinal direction of the liquid delivery tube 11 from the central position of the connection portion, and the nebulizer introduction tube 13 having a length of 10 to 20 times the outer diameter of the nebulizer introduction tube 13 extending in the longitudinal direction of the nebulizer introduction tube 13 from the central position of the connection portion.

[0050] When the fitting portion of the nebulizer introduction tube 13 into the liquid delivery tube 11 becomes detached, since Mφ < nφ at the overlapping portion of the liquid splash prevention tube 17 having an inner diameter of nφ and the nebulizer introduction tube 13 having an outer diameter of Mφ, the liquid sample passes through the overlapping portion and leaks to the outside of the liquid splash prevention tube 17. However, since the mechanical connection between the liquid delivery tube 11 and the nebulizer introduction tube 13 is maintained, it does not scatter or touch the pump 10 and falls onto the apparatus main body tray 40 of the ICP apparatus, and is guided to the leakage countermeasure drain hole 41.

[0051] On the other hand, even when the fitting portion of the nebulizer introduction tube 13 into the liquid delivery tube 11 becomes detached and the outer diameter of the liquid delivery tube 11 contracts from L´φ to Lφ, the inner diameter of the liquid splash prevention tube 17 that encloses the liquid delivery tube 11 also contracts from n´φ to nφ, so Lφ ≈ nφ, and the liquid sample that has leaked through this portion does not pass through. As a result, since the flow of the liquid sample toward the pump 10 side is suppressed, it is preferable from the viewpoint of protecting the pump 10, and the mechanical engagement between the liquid delivery tube 11 and the liquid splash prevention tube 17 is also ensured.

[0052] And by ensuring the mechanical engagement between the liquid delivery tube 11 and the liquid splash prevention tube 17, it is possible to suppress the nebulizer introduction tube 13 that has become detached from the fitting portion between the nebulizer introduction tube 13 and the liquid delivery tube 11 from also becoming detached from the liquid splash prevention tube 17.

[0053] (II) Liquid splash prevention storage container FIG. 5 is a schematic cross-sectional view of a second connection point 15(3) provided with a liquid splash prevention storage container 18. The second connection point 15(3) provided with the liquid splash prevention storage container is the above-described second connection point 15 housed in the liquid splash prevention storage container 18. Note that the liquid splash prevention storage container 18 is a different example of an embodiment related to the member described as the "liquid leakage control member" in the means for solving the problem section.

[0054] The liquid splash prevention storage container 18 is molded from an appropriate resin, and a liquid feed tube side opening 31 and a nebulizer introduction tube side opening 32 are provided at both ends, and for example, has a cylindrical shape covering the second connection point 15 between the liquid feed tube 11 and the nebulizer introduction tube 13. From the opposite ends of the cylindrical liquid splash prevention storage container 18, the liquid feed tube 11 and the nebulizer introduction tube 13 are introduced into the liquid splash prevention storage container 18 while maintaining liquid tightness. And inside the liquid splash prevention storage container 18, the nebulizer introduction tube 13 is fitted and connected to the liquid feed tube 11 to form the second connection point 15.

[0055] Also in the second connection point 15 housed in the liquid splash prevention storage container 18, similar to the second connection point 15 described with reference to FIG. 3, a semi-rigid nebulizer introduction tube 13 having an outer diameter Mφ (where Mφ > lφ) (for example, outer diameter 1.3φ) is fitted into the liquid feed tube 11 (for example, inner diameter 1.03φ, outer diameter 2.8φ) having an inner diameter lφ, an outer diameter Lφ, being soft and stretchable, and is connected as the second connection point 15. At this time, due to the difference in hardness of the materials of the liquid feed tube 11 and the nebulizer introduction tube 13, the inner diameter of the stretchable liquid feed tube 11 expands from lφ to l'φ (where lφ < l'φ), and the outer diameter expands from Lφ to L'φ (where Lφ < L'φ). And the outer diameter Mφ of the nebulizer introduction tube 13 and the inner diameter l'φ of the expanded liquid feed tube 11 are in a state of Mφ ≈ l'φ.

[0056] Then, even when the liquid feed tube 11 and the nebulizer introduction tube 13 become detached at the second connection point 15 due to an increase in liquid pressure, the liquid feed tube 11 is fixed with the liquid feed tube side opening 31 and the nebulizer introduction tube 13 is fixed with the nebulizer introduction tube side opening 32, each maintaining liquid tightness, so that the liquid feed tube 11 and the nebulizer introduction tube 13 do not come out of the liquid splash prevention storage container 18. As a result, even if the inserted portions of the liquid feed tube 11 and the nebulizer introduction tube 13 become detached due to an increase in liquid pressure, the terminals of the liquid feed tube 11 and the terminals of the nebulizer introduction tube 13 are secured within the liquid splash prevention storage container 18, ensuring a mechanical connection between the liquid feed tube 11 and the nebulizer introduction tube 13.

[0057] Also, when the liquid feed tube 11 and the nebulizer introduction tube 13 become detached at the second connection point 15 due to an increase in liquid pressure, a liquid sample leaks into the liquid splash prevention storage container 18. Therefore, it is preferable to provide a drain 43 of the liquid splash prevention storage container as a drain member at an appropriate location of the liquid splash prevention storage container 18, and further provide a drain tube 44 for the liquid splash prevention storage container. This guides the leaked solution to the leakage countermeasure drain hole 41.

[0058] At this time, the length of the overlapping portion between the liquid splash prevention storage container 18 and the liquid feed tube 11, and the length of the overlapping portion between the liquid splash prevention storage container 18 and the nebulizer introduction tube 13 only need to be such that, even when the liquid feed tube 11 and the nebulizer introduction tube 13 become detached, the terminals of the liquid feed tube 11 and the nebulizer introduction tube 13 are secured within the liquid splash prevention storage container 18, maintaining a mechanical connection between the liquid feed tube 11 or the nebulizer introduction tube 13 and the liquid splash prevention storage container 18. This is because if the inserted portion of the nebulizer introduction tube 13 into the liquid feed tube 11 is too long, the liquid splash prevention storage container 18 will become unnecessarily large.

[0059] Specifically, the length D of the liquid splash prevention storage container 18 in the longitudinal direction of the liquid delivery tube 11 from the central position F of the second connection point 15 only needs to be 5 times or more the outer diameter of the liquid delivery tube 11, and preferably 10 times or less. On the other hand, the length E of the liquid splash prevention storage container 18 in the longitudinal direction of the nebulizer introduction tube 13 from the central position F of the second connection point 15 only needs to be 10 times or more the outer diameter of the nebulizer introduction tube 13, and preferably 20 times or less. Note that "the longitudinal direction of the liquid delivery tube from the central position F of the second connection point 15" means the direction from the central position F of the second connection point 15 toward the pump 10, and "the longitudinal direction of the nebulizer introduction tube from the central position F of the second connection point 15" means the direction from the central position F of the second connection point 15 toward the nebulizer 20. That is, the liquid splash prevention storage container 18 only needs to store the liquid delivery tube 11 with a length of 5 times or more and 10 times or less the outer diameter of the liquid delivery tube 11 in the longitudinal direction of the liquid delivery tube 11 from the central position of the connection point, and the nebulizer introduction tube 13 with a length of 10 times or more and 20 times or less the outer diameter of the nebulizer introduction tube 13 in the longitudinal direction of the nebulizer introduction tube 13 from the central position of the connection point, inside the liquid splash prevention storage container.

[0060] When the fitting portion of the nebulizer introduction tube 13 into the liquid delivery tube 11 comes off, the liquid sample leaks into the liquid splash prevention storage container 18. However, since the liquid splash prevention storage container 18 has liquid tightness, it is guided to the leakage prevention drain hole 41 without splashing or touching the pump 10.

[0061] Also, when the insertion part of the liquid delivery tube 11 of the nebulizer introduction tube 13 comes off at the second connection point 15, in order to prevent the liquid delivery tube 11 and the nebulizer introduction tube 13 from coming off from the liquid splash prevention storage container 18, and to maintain the liquid tightness so that the leaked liquid does not flow out from other than the drain tube 44 for the liquid splash prevention storage container, it is preferable to provide a liquid delivery tube side O-ring 33 at the liquid delivery tube side opening 31 and a nebulizer introduction tube side O-ring 34 at the nebulizer introduction tube side opening 32, respectively.

[0062] As described above, the second connection point 15 related to the liquid delivery tube 11 and the nebulizer introduction tube 13, the second connection point 15(2) provided with the liquid splash prevention tube, and further, the second connection point 15(3) provided with the liquid splash prevention storage container have been described.

[0063] By adopting this configuration, the lengths of the solution introduction tube 12, the liquid delivery tube 11, and the nebulizer introduction tube 13 connecting the sample container and the nebulizer 20 can be made substantially the shortest, the amount of solution staying in the tube can be reduced, and the cleaning time of the liquid delivery system during solution replacement can be shortened, which is preferable.

[0064] As described above, the liquid splash prevention tube and the liquid splash prevention storage container according to the present invention have been described with reference to the ICP device. However, the application of the liquid splash prevention tube and the liquid splash prevention storage container according to the present invention is not limited to the ICP device. The liquid splash prevention tube and the liquid splash prevention storage container according to the present invention can be applied to production devices and analytical devices having a small-scale and simple liquid delivery system similar to the ICP device.

Explanation of Reference Numerals

[0065] 1. ICP device 2. Sample introduction part 4. Operation PC 5. Auto sampler 6. Waste liquid container 10. Pump 11. Liquid delivery tube (outer diameter Lφ, inner diameter lφ) 12. Tube for solution introduction 13. Tube for nebulizer introduction (outer diameter Mφ) 14. First connection point 15. Second connection point 15(2). Second connection point provided with a liquid splash prevention tube 15(3). Second connection point provided with a liquid splash prevention storage container 17. Liquid splash prevention tube (inner diameter nφ) 18. Liquid splash prevention storage container 20. Nebulizer 30. Cyclone chamber 31. Liquid feeding tube side opening 32. Nebulizer introduction tube side opening 33. Liquid feeding tube side O-ring 34. Nebulizer introduction tube side O-ring 35. First discharge tube 36. Second discharge tube 37. Third discharge tube 38. Third connection point 39. Fourth connection point 40. Apparatus main body tray 41. Leakage response drain hole 42. Drain tube 43. Drain of liquid splash prevention storage container 44. Drain tube for liquid splash prevention storage container 50. Ar humidifier 151. Pure water container A. In the liquid splash prevention tube, the length from the central position of the second connection point towards the pump direction B. In the liquid splash prevention tube, the length from the central position of the second connection point towards the nebulizer direction C. Central position of the second connection point in the liquid splash prevention tube D. In the liquid splash prevention storage container, the length from the central position of the second connection point towards the pump direction E. In the liquid splash prevention storage container, the length from the central position of the second connection point towards the nebulizer direction F. Central position of the second connection point in the liquid splash prevention storage container

Claims

1. a first tube having a predetermined hardness and an inner diameter; a second tube that is harder than the first tube, has an outer diameter greater than or equal to the inner diameter of the first tube, and can be fitted into the first tube; the second tube is fitted into the first tube to form a fitting portion; the fitting portion constitutes a connection point of the first and second tubes for feeding a liquid through the first and second tubes; a connection point of the tubes provided with a liquid leakage control member at the connection point to control the fitting portion of the second tube into the first tube from coming off when the liquid feed pressure exceeds a predetermined value and the liquid leaks outside from the connection point.

2. the liquid leakage control member is a liquid splash prevention tube having an inner diameter greater than or equal to the outer diameter of the first tube, the liquid splash prevention tube encloses the connection point within the liquid splash prevention tube, when the liquid feed pressure exceeds a predetermined value, the fitting portion comes off, and the liquid leaks outside from the connection point, the liquid splash prevention tube controls the scattering of the liquid leaked from the connection point as a liquid leakage control member. The connection point of the tube provided with the liquid leakage control member according to claim 1, characterized in that.

3. the liquid splash prevention tube encloses, within the liquid splash prevention tube, a first tube having a length of 3 times or more and 5 times or less the outer diameter of the first tube extending from the central position of the connection point in the longitudinal direction of the first tube, and a second tube having a length of 10 times or more and 20 times or less the outer diameter of the second tube extending from the central position of the connection point in the longitudinal direction of the second tube. The connection point of the tube provided with the liquid leakage control member according to claim 2, characterized in that.

4. the liquid leakage control member is a liquid splash prevention storage container that liquid-tightly houses the connection point inside, the liquid splash prevention storage container is provided with a drain member for feeding the liquid leaked outside from the connection point to a desired place. The connection point of the tube provided with the liquid leakage control member according to claim 1, characterized in that it is a liquid leakage control member.

5. The liquid splash prevention storage container stores, within the liquid splash prevention storage container, a first tube having a length of 5 times or more and 10 times or less the outer diameter of the first tube extending from the central position of the connection portion in the longitudinal direction of the first tube, and a second tube having a length of 10 times or more and 20 times or less the outer diameter of the second tube extending from the central position of the connection portion in the longitudinal direction of the second tube. The connection portion of the tube provided with the liquid leakage control member according to claim 4, characterized in that it is provided.

6. An ICP emission spectroscopic analyzer, characterized by having a connection portion of a tube provided with the liquid leakage control member according to any one of claims 1 to 5.

7. An operating method of an ICP emission spectroscopic analyzer, characterized in that a connection portion of a tube provided with the liquid leakage control member according to any one of claims 1 to 5 is provided in the ICP emission spectroscopic analyzer, and liquid is fed to a nebulizer of the ICP emission spectroscopic analyzer.

Images