Sample gas supply device

Abstract

Miniaturize the device that supplies the sample gas to the ion source. [Solution] The structure 20 consists of an integrated flow control valve 22 and nozzle 24. Valves (on / off valves) 28, 48 are provided around the structure 20. The central axes C3, C4 of the valves 28, 48 are parallel to the central axes C1, C2 of the structure 20. The flow control valve 22 has a housing 66 and a moving body 54. The housing 66 has three branch ports and an orifice. The moving body 54 has a needle 60. The flow rate of the sample gas is adjusted by adjusting the amount the needle 60 is inserted into the orifice.

Description

Technical Field

[0001] The present invention relates to a sample gas supply device, and particularly to an apparatus for supplying sample gas to an ion source.

Background Art

[0002] A mass spectrometer has an ion source. Various ion sources conforming to various ionization methods are in use. Ion sources capable of selectively using a plurality of ionization methods are also known.

[0003] Standard samples are used for calibration, tuning and the like of mass spectrometers. Specifically, sample gas generated by vaporization of the standard sample is introduced into the ion source. The sample gas is ionized in the ion source, and the resulting ions are subjected to mass spectrometry. The mass spectrometer is adjusted based on the results of the mass spectrometry. An apparatus used for sending the sample gas to the ion source is the sample gas supply device. The sample gas supply device is also referred to as a sample gas introduction device or a sample introduction device.

[0004] The sample gas supply device disclosed in Patent Document 1 includes a sample container, a flow rate adjustment valve, a rotary pump, a nozzle and the like. The sample gas supply device disclosed in Patent Document 2 is provided with a plurality of sample gas introduction units.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of Invention

Problems to be Solved by the Invention

[0006] Sample gas supply devices, such as those disclosed in Patent Document 1, are assemblies of multiple components and tend to be large. The object of the present invention is to miniaturize the sample gas supply device. [Means for solving the problem]

[0007] The sample gas supply device according to the present invention includes a plurality of units, each containing at least one sample gas source; a nozzle for releasing sample gas; and a flow rate adjustment valve having a plurality of branch ports connected to the plurality of units and an orifice connected to the nozzle, wherein the plurality of branch ports are spatially connected to each other, and the flow rate adjustment valve adjusts the flow rate of the sample gas discharged from the orifice. [Effects of the Invention]

[0008] According to the present invention, since the flow control valve itself has multiple branch ports, there is no need to provide a member for flow path branching on the outside of the flow control valve. Therefore, it is possible to miniaturize the sample gas supply device. [Brief explanation of the drawing]

[0009] [Figure 1] This figure shows an example of the configuration of a sample gas supply device according to an embodiment. [Figure 2] This is a side view of a sample gas supply device according to an embodiment. [Figure 3] This is a plan view of a sample gas supply device according to an embodiment. [Figure 4] This is a cross-sectional view of a sample gas supply device according to an embodiment. [Figure 5] This figure shows a first example of operation for multiple valves. [Figure 6] This figure shows a second example of the operation of multiple valves. [Figure 7] This diagram shows the setting of the needle's range of motion. [Figure 8] This is a diagram showing an example display. [Modes for carrying out the invention]

[0010] The embodiments will be described below with reference to the drawings.

[0011] (1) Outline of the Embodiment The sample gas supply device according to this embodiment has a plurality of units, a nozzle, and a flow rate adjustment valve. The plurality of units include at least one sample gas source. The nozzle releases the sample gas. The flow rate adjustment valve has a plurality of branch ports connected to the plurality of units and an orifice connected to the nozzle. In the flow rate adjustment valve, the plurality of branch ports are spatially connected to each other. The flow rate adjustment valve adjusts the flow rate of the sample gas exiting the orifice.

[0012] According to the above configuration, since the flow control valve itself has multiple branch ports, there is no need to provide a member for flow path branching on the outside of the flow control valve. Therefore, it is possible to miniaturize the sample gas supply device. In the embodiment, the flow control valve has two or three or more branch ports.

[0013] The sample gas source is, for example, a container containing a standard sample. The standard sample vaporizes within the container, thereby generating the sample gas. The standard sample may be vaporized outside the container. Multiple sample gas sources may be included in multiple units connected to a flow control valve. The flow control valve is, in embodiment, a needle valve. Other types of valves may be used as the flow control valve. In the flow control valve, when the flow rate is zero, the multiple branches and the orifice are spatially separated, while in other states, the multiple branches and the orifice are spatially connected. The orifice may also be called an outlet or discharge port. The multiple branches and multiple units are connected directly or indirectly. Preferably, corresponding branches and units are connected via connecting members and on / off valves. The orifice and nozzle are connected directly or indirectly. Preferably, the orifice and nozzle are directly connected.

[0014] In an embodiment, the flow rate adjustment valve has a housing and a moving body. The housing includes a plurality of branch ports and orifices. The moving body includes a needle inserted into the orifice and moves inside the housing. The plurality of branch ports are spatially communicated with each other through the internal space of the housing. The flow rate is adjusted by adjusting the insertion amount of the needle into the orifice. The housing may also be referred to as a syringe.

[0015] The sample gas supply device according to the embodiment includes a plurality of on-off valves provided on a plurality of branch paths communicating with the plurality of branch ports. Each of the above plurality of units corresponds to a facility or apparatus and has an on-off valve.

[0016] The sample gas supply device according to the embodiment includes a motor that applies a driving force for flow rate adjustment to the flow rate adjustment valve. The motor is provided on the central axis of the flow rate adjustment valve. According to this configuration, for example, when a plurality of on-off valves are installed around the flow rate adjustment valve, the motor does not become an obstacle. Alternatively, the compactness of the sample gas supply device including the motor can be increased.

[0017] In the embodiment, the central axis of the nozzle and the central axis of the flow rate adjustment valve coincide with each other. The central axis of the nozzle may be inclined with respect to the central axis of the flow rate adjustment valve. Alternatively, a curved nozzle may be used.

[0018] In the embodiment, the nozzle is coupled to the housing. That is, the nozzle is directly connected to the housing, and more specifically, the nozzle is integrated with the housing. According to this configuration, the size of the sample gas supply device can be further reduced. In addition, heat conduction from the housing to the nozzle can be improved. A nozzle having a thick-walled main body may be used. The orifice in the housing is in contact with the internal space of the nozzle.

[0019] In this embodiment, the tip of the needle enters the nozzle when the orifice is blocked by the needle. However, various flow rate adjustment structures can be used. In this embodiment, the nozzle is coupled to the housing. This configuration reduces the number of parts.

[0020] In one embodiment, multiple branch lines extend outward from multiple branch openings along a plane perpendicular to the central axis of the flow control valve. This configuration allows, for example, multiple on / off valves to be placed within the space surrounding the flow control valve. In another embodiment, multiple branch lines extend radially from multiple branch openings outward. Each of the multiple branch lines is a flow path.

[0021] In this embodiment, the central axis of each on / off valve is parallel to the central axis of the flow control valve. This configuration allows for a higher density of valves or reduces dead space within the flow control device.

[0022] In this embodiment, a heater is provided in the flow control valve. The flow control valve and a plurality of on-off valves are connected via a plurality of heat conductive members. With this configuration, the heat generated by the heater is transferred to the plurality of on-off valves via the plurality of heat conductive members. Heating of each member can prevent or reduce adhesion or liquefaction of the sample gas. The heat conductive members are, for example, hollow connecting members or pipes.

[0023] In the embodiment, each heat conduction member has a proximal end connected to a flow control valve and a distal end connected to each on / off valve. A recess may be provided in the flow control valve to engage with the proximal end. A recess may be provided in each on / off valve to engage with the distal end. Such a configuration allows for good heat conductivity. In the embodiment, the plurality of units include at least one sample gas source and at least one exhaust pump.

[0024] (2) Details of the embodiment Figure 1 shows a mass spectrometry system according to an embodiment. The mass spectrometry system performs mass spectrometry on a sample and generates a mass spectrum. The sample is qualitatively or quantitatively analyzed by analyzing the mass spectrum.

[0025] The mass spectrometry system comprises a mass spectrometer 10 and a sample gas supply device 12. The sample gas supply device 12 supplies sample gas generated from standard samples to the mass spectrometer 10 for tuning, calibration, etc. As described later, the sample gas supply device 12 selectively supplies multiple standard sample gases to the mass spectrometer 10. The mass spectrometry system may also include a gas chromatograph.

[0026] In Figure 1, the mass spectrometer 10 has a vacuum chamber 13. An ion source 14, a mass spectrometer 16, and a detector 18 are arranged inside the vacuum chamber 13. The ion source 14 ionizes, for example, a sample sent from a gas chromatograph. The ion source 14 has a first function of generating ions according to a first ionization method, and a second function of generating ions according to a second ionization method. For example, the first ionization method is the electron ionization method. The second ionization method is an ionization method other than the electron ionization method (e.g., chemical ionization method, field ionization method). Typically, the ionization method to be used is selected in advance.

[0027] The mass spectrometer 16 is, for example, a quadrupole mass spectrometer or a time-of-flight mass spectrometer. The detector 18 detects ions emitted from the mass spectrometer 16.

[0028] The sample gas supply device 12 is connected to the mass spectrometer 10. The sample gas supply device 12 has a structure (central structure) 20. The central structure 20 has a flow control valve 22 and a nozzle 24. Furthermore, the central structure 20 has a coupling 56 and a motor 58. The motor 58 is, for example, a stepping motor. The sample gas is released from the nozzle 24 to the ion source 14. The ions generated by the ionization of the sample gas are subjected to mass spectrometry. Based on the results of the mass spectrometry, tuning or calibration of the mass spectrometer 10 is performed.

[0029] The flow control valve 22 is specifically a needle valve. The flow control valve 22 has a hollow housing and a moving body 54. The moving body 54 moves within the housing. The moving body 54 is equipped with a needle 60.

[0030] In this embodiment, the flow control valve 22 has a first port P1, a second port P2, a third port P3, and an outlet port P0. The first port P1, the second port P2, and the third port P3 are branch ports (primary ports), respectively. The outlet port P0 is a secondary port. The internal spaces of the first port P1, the second port P2, and the third port P3 are interconnected. These three internal spaces are referred to as the primary space.

[0031] The outlet port P0 has an orifice that functions as a diaphragm, into which the needle 60 is inserted. When the needle completely blocks the orifice, the primary space and the internal space (secondary space) of the nozzle 24 are completely separated. The amount of needle 60 inserted into the orifice determines the amount (flow rate) of sample gas flowing from the primary space to the secondary space.

[0032] A first flow path (first branch path) is connected to the first port P1. More specifically, the first port P1 has a first branch opening, and the first branch opening is connected to the first flow path. A first valve 28 is provided on the first flow path. The first valve 28 is an on / off valve. An example of an on / off valve is a solenoid valve. The first flow path includes a flow path 26 between the first port P1 and the first valve 28, and a flow path 30 between the first valve 28 and the first standard sample container 32.

[0033] A second flow path (second branch path) is connected to the second port P2. More specifically, the second port P2 has a second branch opening, and the second branch opening is connected to the second flow path. A second valve 38 is provided on the second flow path. The second valve 38 is an on / off valve. The second flow path includes a flow path 36 between the second port P2 and the second valve 38, and a flow path 40 between the second valve 38 and the second standard sample container 42.

[0034] A third flow path (third branch path) is connected to the third port P3. More specifically, the third port P3 has a third branch port, and the third branch port is connected to the third flow path. A third valve 48 is provided on the third flow path. The third valve 48 is an on / off valve. The third flow path includes a flow path 46 between the third port P3 and the third valve 48, and a flow path 50 between the third valve 48 and the pump 52. The pump 52 is an exhaust pump, for example, a rotary pump.

[0035] The first standard sample container 32, the second standard sample container 42, and the pump 52 are multiple units (multiple pieces of equipment) in the sample gas supply device 12. Three or more standard sample containers may be provided. In that case, four or more branch ports may be provided in the flow control valve 22. The pump 52 is a unit (piece of equipment) for sucking gas in multiple flow paths and gas in the flow control valve 22. The first standard sample 34 is contained in the first standard sample container 32. The second standard sample 44 is contained in the second standard sample container 42. Normally, the first standard sample 34 vaporizes in the first standard sample container 32, and the second standard sample 44 vaporizes in the second standard sample container 42.

[0036] The controller 62 is comprised, for example, a CPU that executes programs. The controller 62 controls the operation of the flow control valve 22, valves 28, 38, 48, and pump 52. The controller 62 also controls the operation of the cartridge heater, which will be described later. The controller 62 controls the operation of the mass spectrometer 10 as needed.

[0037] Figure 2 is a side view of the sample gas supply device. The X direction is the first horizontal direction, and the Z direction is the vertical direction. The Y direction is the direction that penetrates the plane of the paper in Figure 2, and it is the second horizontal direction. An ion source 14 is provided inside the vacuum chamber 13.

[0038] The sample gas supply device has a main body 12A and a cover 12B. Various units are provided inside the cover 12B. A first standard sample container 32 and a second standard sample container 42 are provided on the cover 12B. A pipe 30A connected to a first valve is connected to the first standard sample container 32, and a pipe 40A connected to a second valve is connected to the second standard sample container 42.

[0039] The tip of the nozzle 24 is connected to the ion source 14 via a connecting component 64. The sample gas released from the tip opening of the nozzle 24 enters the interior of the ion source 14. This causes the sample gas to be ionized.

[0040] Figure 3 is a plan view of the sample gas supply device. The direction of the central axis of the flow rate adjustment valve 22 is defined as the z direction. The directions perpendicular to the z direction are the x and y directions. Figure 3 shows the sample gas supply device as viewed from the z direction.

[0041] The structure (central structure) 20 is composed of a flow control valve 22 and a nozzle (not shown). The first structure 100, the second structure 102, and the third structure 104 are arranged around the structure 20. The first structure 100 has a first valve 28. The second structure 102 has a second valve 38. The third structure 104 has a third valve 48.

[0042] The first valve 28, the second valve 38, and the third valve 48 are each on / off valves. The first valve 28, the second valve 38, and the third valve 48 each extend in the z direction and have a central axis parallel to the z direction. This central axis is parallel to the central axis of the flow control valve 22. The sides of the first valve 28, the second valve 38, and the third valve 48 are close to or in contact with the sides of the flow control valve 22.

[0043] The flow control valve 22 has a hollow housing 66 and a moving body 54. The moving body 54 is equipped with a needle. In the illustrated example, the housing 66 has a generally cylindrical shape. The central axis of the flow control valve 22 is parallel to the z direction, and its central axis coincides with the central axis of the moving body 54, i.e., the central axis of the needle. A cartridge heater 67 is embedded in the housing 66.

[0044] The housing 66 has an internal space. The moving body 54 moves along the z-direction within this internal space. The housing 66 has a first port P1, a second port P2, and a third port P3, that is, a first branch port A1, a second branch port A2, and a third branch port A3. These branch ports A1, A2, and A3 are connected to each other through the internal space of the housing 66. Each of these branch ports A1, A2, and A3 faces a direction perpendicular to the z-direction. In the plane defined by the x-direction and y-direction (xy-plane), if the angle in the x-direction is defined as 0 degrees, the angle that the first branch port A1 faces is 0 degrees, the angle that the second branch port A2 faces is 90 degrees, and the angle that the third branch port A3 faces is 180 degrees. These angles may also be set to 120 degrees each.

[0045] As already explained, the first channel is connected to the first branch port A1. The second channel is connected to the second branch port A2. The third channel is connected to the third branch port A3. The first, second, and third channels radiate outwards along the xy-plane.

[0046] In the xy-plane, the angle of the first flow path with respect to the x-direction is 0 degrees. A first valve 28 is provided on the first flow path. A first internal connecting member 80 is provided spanning the flow control valve 22 and the first valve 28. The proximal end 80A of the first internal connecting member 80 is inserted into a recess 106 formed in the flow control valve 22, and the proximal end 80A and the recess 106 are connected. Specifically, a male thread is formed on the surface of the proximal end 80A, and a female thread is formed on the surface of the recess 106, and the male and female threads are screwed together.

[0047] The distal end 80B of the first inner connecting member 80 is inserted into a recess 108 formed in the first valve 28, and the distal end 80B and the recess 108 are connected. Specifically, a male thread is formed on the surface of the distal end 80B, and a female thread is formed on the surface of the recess 108, and the male thread and the female thread are screwed together. The first inner connecting member 80 has a flow path 26 which corresponds to a part of the first flow path.

[0048] A first external connecting member 86 is provided between the first valve 28 and the first standard sample container. The proximal end 86A of the first external connecting member 86 is inserted into a recess 110 formed in the first valve 28, and the proximal end 86A and the recess 110 are connected. Specifically, a male thread is formed on the surface of the proximal end 86A, and a female thread is formed on the surface of the recess 110, and the male and female threads are screwed together. The first external connecting member 86 has a flow path 30 which corresponds to a part of the first flow path.

[0049] In the xy-plane, the angle of the second flow path with respect to the x-direction is 90 degrees. A second valve 38 is provided on the second flow path. A second internal connecting member 82 is provided spanning the flow control valve 22 and the second valve 38. The proximal end 82A of the second internal connecting member 82 is inserted into a recess 112 formed in the flow control valve 22, and the proximal end 82A and the recess 112 are connected. Specifically, a male thread is formed on the surface of the proximal end 82A, and a female thread is formed on the surface of the recess 112, and the male and female threads are screwed together.

[0050] The distal end 82B of the second inner connecting member 82 is inserted into a recess 114 formed in the second valve 38, and the distal end 82B and the recess 114 are connected. Specifically, a male thread is formed on the surface of the distal end 82B, and a female thread is formed on the surface of the recess 114, and the male and female threads are screwed together. The second inner connecting member 82 has a flow path 36 which corresponds to a part of the second flow path.

[0051] A second external connecting member 88 is provided between the second valve 38 and the second standard sample container. The proximal end 88A of the second external connecting member 88 is inserted into a recess 116 formed in the second valve 38, and the proximal end 88A and the recess 116 are connected. Specifically, a male thread is formed on the surface of the proximal end 88A, and a female thread is formed on the surface of the recess 116, and the male and female threads are screwed together. The second external connecting member 88 has a flow path 40 which corresponds to a part of the second flow path.

[0052] In the xy-plane, the angle of the third flow path with respect to the x-direction is 180 degrees. A third valve 48 is provided on the third flow path. A third internal connecting member 84 is provided spanning the flow control valve 22 and the third valve 48. The proximal end 84A of the third internal connecting member 84 is inserted into a recess 118 formed in the flow control valve 22, and the proximal end 84A and the recess 118 are connected. Specifically, a male thread is formed on the surface of the proximal end 84A, and a female thread is formed on the surface of the recess 118, and the male and female threads are screwed together.

[0053] The distal end 84B of the third inner connecting member 84 is inserted into a recess 120 formed in the third valve 48, and the distal end 84B and the recess 120 are connected. Specifically, a male thread is formed on the surface of the distal end 84B, and a female thread is formed on the surface of the recess 120, and the male and female threads are screwed together. The third inner connecting member 84 has a flow path 46 which corresponds to a part of the third flow path.

[0054] A third external connecting member 90 is provided between the third valve 48 and the pump. The proximal end 90A of the third external connecting member 90 is inserted into a recess 122 formed in the third valve 48, and the proximal end 90A and the recess 122 are connected. Specifically, a male thread is formed on the surface of the proximal end 90A, and a female thread is formed on the surface of the recess 122, and the male and female threads are screwed together. The third external connecting member 90 has a flow path 50 which corresponds to a part of the third flow path.

[0055] The heat generated by the cartridge heater 67 is transferred from the flow control valve 22 to the first valve 28 via the first internal connecting member 80. Furthermore, the heat generated by the cartridge heater 67 is transferred from the flow control valve 22 to the second valve 38 via the second internal connecting member 82. Finally, the heat generated by the cartridge heater 67 is transferred from the flow control valve 22 to the third valve 48 via the third internal connecting member 84.

[0056] As shown in Figure 3, multiple structures 20, 100, 102, and 104 are arranged in close proximity. In other words, multiple valves 22, 28, 38, and 48 are arranged in close proximity. Furthermore, there is good thermal conductivity between the flow control valve 22 and the multiple valves 28, 38, and 48. In the xy plane, the first, second, and third flow paths may be provided at 120-degree angular intervals. Four or more flow paths may be provided. Adhesive is introduced into the threaded portion of the male and female screws to increase the vacuum level.

[0057] Figure 4 shows an xz cross-section of the sample gas supply device. As already described, the structure 20 consists of a flow control valve 22 and a nozzle 24. The flow control valve 22 has a housing 66 and a moving body 54. The moving body 54 moves along the central axis C2 of the flow control valve 22 and is equipped with a needle 60.

[0058] The moving body 54 is connected to the motor 58 via a coupling 56. The rotational force generated by the motor 58 is transmitted to the moving body 54 via the coupling 56. The conversion mechanism 68 is a mechanism that converts rotational motion into linear motion. The conversion mechanism 68 has a male thread formed on the rotating shaft 70 and a female thread formed inside the moving body 54. The male and female threads are screwed together. The conversion mechanism 68 has a projection 72 that functions as a rotation stopper. The projection 72 is inserted into a groove formed in the housing 66 that extends in the z direction.

[0059] The moving body 54 has an O-ring 73 that functions as a sealing member. The O-ring 73 seals the space between the outer surface of the moving body 54 and the inner surface of the housing 66.

[0060] The housing 66 has an outlet port P0 equipped with an orifice. Specifically, an orifice plate 74, which forms part of the housing 66, has an orifice. The tip of the needle 60 is inserted into this orifice. The amount of insertion of the needle 60 into the orifice determines the flow rate of the sample gas exiting the orifice.

[0061] In Figure 4, A indicates the portion where the nozzle 24 is located. The nozzle 24 has a nozzle body 75 and a flow path 76 formed inside it. An orifice is in contact with the flow path 76. When the orifice is blocked by the needle 60, the tip of the needle enters the flow path 76. The nozzle body 75 extends along the z direction and has a thick-walled structure. The nozzle body 75 and a part of the housing 66 are integrated, meaning they are made of a single component. This reduces the number of components that make up the flow control valve 22 and also improves heat conductivity from the flow control valve 22 to the nozzle 24.

[0062] The first branch port in the first port P1, the second branch port in the second port, and the third branch port in the third port P3 are connected via the internal space of the housing 66. Figure 4 shows the first internal connecting member 80, the first valve 28, and the first external connecting member 86. The first branch port is connected to the first valve 28 via the flow path 26 in the first internal connecting member 80. The flow path 30 in the first external connecting member 86 is connected to the first valve 28. Figure 4 also shows the third internal connecting member 84, the third valve 48, and the third external connecting member 90. The third branch port is connected to the third valve 48 via the flow path 46 in the third internal connecting member 84. The flow path 50 in the third external connecting member 90 is connected to the third valve 48.

[0063] The central axis C1 of the nozzle 24 coincides with the central axis C2 of the flow control valve 22. The central axis C3 of the first valve 28, the central axis of the second valve, and the central axis C4 of the third valve are parallel to the central axes C1 and C2. The coupling 56 and motor 58 are positioned on the central axis C2. The flow control valve 22, the first valve 28, the second valve, and the third valve 48 each have a generally cylindrical shape. In order to improve suction efficiency, the inner diameters of the flow paths 46 and 50 constituting the third branch are larger than the inner diameters of the flow paths 26 and 30 constituting the first branch (and the inner diameters of the two flow paths constituting the second branch).

[0064] Figure 5 shows the first operation example of the three valves 28, 38, and 48. In the stopped state (when no sample gas is supplied), valves 28, 38, and 48 are all in the closed state (see S10). Prior to the supply of sample gas, only the third valve 48 opens. Also, immediately after the supply of sample gas, only the third valve 48 opens (see S12). When the flow control valve is in the closed state, the pump sucks the internal space of the flow control valve and each flow path, creating a vacuum. After the suction, the third valve 48 closes.

[0065] When using the first standard sample, only the first valve 28 is opened (see S14), and the first sample gas generated in the first standard sample container is sent to the ion source through the first valve 28, the flow rate adjustment valve, and the nozzle. On the other hand, when using the second standard sample, only the second valve 38 is opened (see S16), and the second sample gas generated in the second standard sample container is sent to the ion source through the second valve 38, the flow rate adjustment valve, and the nozzle. The flow rates of the first and second sample gases are adjusted by the flow rate adjustment valve.

[0066] Furthermore, in order to make the drop in gas flow rate steeper when the first valve 28 or the second valve 38 is closed, the third valve 48 may be opened immediately after the first valve 28 or the second valve 38 is closed, and the pump may be made to perform a suction operation. Also, when the pump is to perform a suction operation for a long period of time, the state of the third valve 48 may be switched according to the device operating mode.

[0067] Figure 6 shows a second example of the operation of the three valves 28, 38, and 48. When the supply of sample gas is stopped, the three valves 28, 38, and 48 are in the closed state (see S10). Prior to the supply of sample gas, the three valves 28, 38, and 48 temporarily close. Then, the third valve 48 opens (see S12A). When using the first standard sample, the first valve 28 opens (see S14A). When using the second standard sample, the second valve 38 opens (see S16A). Since the three valves 28, 38, and 48 are closed immediately after the opening of valve 28 or valve 38, there is no moment when the first standard sample container or the second standard sample container is directly connected to the pump due to delays in valve operation, etc.

[0068] Figure 7 shows how to set the range of motion of the moving object. In S20, the motor is rotated in the positive direction with a constant torque, causing the moving object to move forward. The needle is inserted into the orifice. In S22, the forward motion of the object is restricted, and when the torque exceeds the first threshold, the forward end is detected. At that point, the rotation in the positive direction is stopped. In S24, the motor is rotated in the negative direction for the number of revolutions of the first rotation. The stopping position is defined as the lower limit.

[0069] Next, in S26, the motor is rotated in the negative direction with a constant torque, causing the moving object to move backward. In S28, when the backward movement of the moving object is restricted and a torque exceeding the second threshold is generated, the backward end is detected. At that point, the rotation in the negative direction is stopped. In S30, the motor is rotated in the positive direction for the duration of the second rotation. The stopping position is defined as the upper limit.

[0070] For example, the lower limit corresponds to an opening ratio of 0%, and the upper limit corresponds to an opening ratio of 100%. By limiting the range of motion of the moving body to between the lower and upper limits, it is possible to prevent excessive force from being generated inside the flow control valve. In other words, it is possible to prevent damage to the parts. The amount of rotation of the motor, i.e., the number of steps B, can be calculated, for example, from equation (1) below.

[0071] B=Aperture ratio×(Upper limit - Lower limit) / 100 (1)

[0072] Figure 8 shows how to set the aperture. Image 92, which serves as the user interface, has a scale 94 that represents the magnitude of the aperture. By operating button 98, an indicator 96 moves along the scale 94. The indicator 96 shows the aperture. The aperture is also displayed as a numerical value 99.

[0073] In the above embodiment, since the flow control valve has three branch ports, there is no need to provide a flow path branching member on the outside of the flow control valve. Also, the flow control valve and nozzle are integrated. Furthermore, multiple valves are densely arranged around the flow control valve. Therefore, the sample gas supply device can be miniaturized. In addition, it is possible to effectively transfer the heat generated by the heater located in the central structure to the multiple structures. [Explanation of Symbols]

[0074] 10 Mass spectrometer, 12 Sample gas supply device, 14 Ion source, 20 Structure, 22 Flow control valve, 24 Nozzle, 28 Valve (on / off valve), 32 First standard sample container, 42 Second standard sample container, 54 Moving body, 56 Coupling, 58 Motor, 60 Needle, 62 Controller, 80, 82, 84 Connecting members.

Claims

1. Multiple units including at least one sample gas source, A nozzle for releasing the sample gas, A flow control valve having multiple branch ports connected to the multiple units and an orifice connected to the nozzle, Includes, In the flow control valve, the multiple branch ports are spatially connected to each other. The flow rate adjustment valve adjusts the flow rate of the sample gas exiting the orifice. A sample gas supply device characterized by the following features.

2. In the sample gas supply device according to claim 1, The aforementioned flow control valve is A housing having the aforementioned multiple branch ports and the aforementioned orifice, A moving body comprising a needle inserted into the orifice and moving inside the housing, including, A sample gas supply device characterized by the following features.

3. In the sample gas supply device according to claim 1, This includes a plurality of on / off valves provided on a plurality of branch paths connected to the plurality of branch outlets, A sample gas supply device characterized by the following features.

4. In the sample gas supply device according to claim 1, Includes a motor that provides a driving force for flow control to the aforementioned flow control valve, The motor is mounted on the central axis of the flow control valve. A sample gas supply device characterized by the following features.

5. In the sample gas supply device according to claim 1, The central axis of the nozzle and the central axis of the flow control valve coincide. A sample gas supply device characterized by the following features.

6. In the sample gas supply device according to claim 2, The nozzle is coupled to the housing. A sample gas supply device characterized by the following features.

7. In the sample gas supply device according to claim 2, With the orifice blocked by the needle, the tip of the needle enters the nozzle. A sample gas supply device characterized by the following features.

8. In the sample gas supply device according to claim 3, The aforementioned multiple branch lines extend outward from the multiple branch openings along a plane perpendicular to the central axis of the flow control valve. A sample gas supply device characterized by the following features.

9. In the sample gas supply device according to claim 3, The central axis of each of the aforementioned on / off valves is parallel to the central axis of the flow control valve. A sample gas supply device characterized by the following features.

10. In the sample gas supply device according to claim 3, The flow control valve is equipped with a heater. The flow control valve and the plurality of on / off valves are connected via a plurality of heat conductive members. A sample gas supply device characterized by the following features.

11. In the sample gas supply device according to claim 10, Each of the aforementioned heat conductive members is The proximal end connected to the flow control valve, The distal end connected to each of the aforementioned on / off valves, A sample gas supply device characterized by having the following features.

12. In the sample gas supply device according to claim 1, The plurality of units include at least one sample gas source and at least one exhaust pump. A sample gas supply device characterized by the following features.

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