JP6224823B2 - Mass spectrometer and cartridge used in mass spectrometer - Google Patents

Description

  The present invention relates to a mass spectrometer suitable for reduction in size and weight and a cartridge used in the mass spectrometer.

  In the mass spectrometer, the ionized measurement sample is subjected to mass analysis in a mass analyzer. The mass spectrometer is housed in a vacuum chamber and kept at a high vacuum of 0.1 Pa or less, while the measurement sample is ionized at atmospheric pressure as disclosed in Patent Document 1. In addition, since the ionization is performed under a reduced pressure of about 10 to 100 Pa as disclosed in Patent Document 2, there is a difference between the pressure under the ionization environment and the pressure under the mass spectrometry environment. For this reason, in order to introduce the ionized measurement sample into the mass analyzer while maintaining the degree of vacuum (pressure) of the mass analyzer in a range where mass analysis is possible, the differential exhaust as shown in Patent Document 3 is performed. A scheme has been proposed. Patent Document 4 proposes a method of intermittently introducing an ionized measurement sample into the mass spectrometer in addition to the differential exhaust method.

US Pat. No. 6,064,320 U.S. Pat. No. 4,849,628 US Pat. No. 7,592,589 International Publication No. 2009/023361

  According to the method of intermittently introducing the ionized measurement sample of Patent Document 4 into the mass analysis unit, the degree of vacuum of the mass analysis unit reduced by the introduction is recovered while the introduction is stopped, and under high vacuum Mass spectrometry can be performed. This method is advantageous in reducing the size and weight of the mass spectrometer because the mass analyzer can be made high vacuum even with a small vacuum pump.

  However, the method of intermittently introducing the ionized measurement sample of Patent Document 4 into the mass spectrometric section is that the silicon tube opened and closed by a stainless capillary or a pinch valve for adjusting the gas amount of the measurement sample to be intermittently introduced is measured. In the worst case, it is necessary to replace the stainless capillary or silicon tube for each measurement because it may be contaminated with the sample gas and cause a carry-over problem. Although there is a means for preventing contamination by heating, it leads to an increase in the number of heaters, power supplies, batteries, etc., so it is not suitable for making the mass spectrometer smaller and lighter. Further, in order to prevent contamination at a sufficient level, it is generally necessary to heat the pipe to 200 ° C. or higher, so that it cannot be applied to a pinch valve using a resin elastic tube such as a silicon tube.

  Therefore, the problem to be solved by the present invention is to provide a mass spectrometer and a cartridge that are small and light and capable of high-accuracy mass analysis.

The present invention includes a sample introduction unit that introduces a measurement sample and is detachable from a main body, a heating unit that gasifies the measurement sample by heating to generate a sample gas, an ion source that ionizes the sample gas, and an ionization A mass analyzer that separates the sample gas, and the ion source is depressurized internally by differential exhaust from the mass analyzer, and the sample introduction unit includes a measurement container that holds the measurement sample; An introduction pipe for intermittently introducing the sample gas generated in the measurement container into the ion source, and the heating unit includes a first heater for gasifying the measurement sample, and the gasified sample gas A second heater for heating the staying space , wherein the second heater is supported by a resin member, and the resin member is supported by a metal member .

  ADVANTAGE OF THE INVENTION According to this invention, the cartridge used for a mass spectrometer and a mass spectrometer which are small and lightweight and can perform a highly accurate mass analysis can be provided.

1 is an overall configuration diagram of a mass spectrometer according to an embodiment of the present invention. It is a block diagram of the mass spectrometer part of the mass spectrometer which concerns on embodiment of this invention. It is a side view which shows a cartridge (for liquids). It is sectional drawing which shows a cartridge (for liquids). It is a side view which shows a cartridge (for solids). It is sectional drawing which shows a cartridge (for solids). It is AA sectional drawing of FIG. 3B. It is process drawing which shows the adhesion procedure of the solid sample to a heating probe. It is a side view which shows the structure which supports an upper heater and a lower heater. It is a side view which shows the detailed support structure of a lower heater. It is a top view (1st state) which shows the mass spectrometer (cartridge for liquid mounting) which concerns on embodiment of this invention. It is a front view (1st state) which shows the mass spectrometer (cartridge attachment for liquids) which concerns on embodiment of this invention. It is a side view (1st state) which shows the mass spectrometer (mounting cartridge for liquids) which concerns on embodiment of this invention. It is a front view which shows the valve body side of a pinch valve. It is a top view (2nd state) which shows the mass spectrometer (equipped with the measurement container for liquids) which concerns on embodiment of this invention. It is a side view (2nd state) which shows the mass spectrometer (equipped with the measurement container for liquids) which concerns on embodiment of this invention. It is a top view (3rd state) which shows the mass spectrometer (equipped with the measurement container for liquids) which concerns on embodiment of this invention. It is a front view (3rd state) which shows the mass spectrometer (equipped with the measurement container for liquids) which concerns on embodiment of this invention. It is a side view (3rd state) which shows the mass spectrometer (equipped with the measurement container for liquids) which concerns on embodiment of this invention. It is a side view (1st state) which shows the mass spectrometer (equipped with the measurement container for solids) which concerns on embodiment of this invention. It is a side view (2nd state) which shows the mass spectrometer (equipped with the measurement container for solids) which concerns on embodiment of this invention. It is a side view (3rd state) which shows the mass spectrometer (equipped with the measurement container for solids) which concerns on embodiment of this invention. It is a flowchart of the mass spectrometry method implemented with the mass spectrometer which concerns on embodiment of this invention. It is a graph which shows the pressure fluctuation of the internal pressure (b) of a dielectric container, and the pressure fluctuation of the internal pressure (c) of a vacuum chamber accompanying opening and closing of a pinch valve (a). Corresponding to the sequence of the mass spectrometry method (ion accumulation-exhaust waiting time-ion selection-ion dissociation-mass scan) in the mass spectrometer in which the measurement container according to the embodiment of the present invention is attached to the sample introduction unit, (a) pinch Valve opening / closing, (b) pressure of barrier discharge part, (c) pressure of mass analysis part, (d) barrier discharge electrode AC voltage, (e) orifice DC voltage, (f) incap electrode / end cap electrode DC voltage (G) Trap bias DC voltage (h) Trap RF voltage, (i) Auxiliary AC voltage, (j) ON / OFF of ion detector.

  Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. In each figure, common portions are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1A is an overall configuration diagram of a mass spectrometer according to an embodiment of the present invention. First, the overall configuration of the mass spectrometer will be described with reference to FIG. 1A. Then, details of each component of the slide valve 103, the cartridge 104A, the pinch valve 105 (valve), the lower heater 110, and the upper heater 120 will be described.

  As shown in FIG. 1A, a mass spectrometer 100 includes a mass analyzer 101, an ion source 102, a slide valve (gate valve) 103, a cartridge (sample introduction unit) 104A, a pinch valve 105, a lower heater 110 (heating unit, second unit). 1 heater), upper heater 120 (heating unit, second heater) and the like. In FIG. 1, the case where the measurement sample is a liquid will be described as an example.

  The mass analyzer 101 is accommodated in the vacuum chamber 30. Although details will be described later, the mass analyzer 101 can separate target ions from the ionized measurement sample (liquid) 18 by performing ion accumulation, ion selection, ion dissociation, mass scanning, and the like.

  A turbo molecular pump 36 and a roughing pump 37 are connected to the vacuum chamber 30 in series. A turbo molecular pump 36 and a roughing pump 37 are arranged in this order from the vacuum chamber 30 side. Thereby, the inside of the vacuum chamber 30 can be decompressed to a high vacuum of about 0.1 Pa or less.

  The vacuum chamber 30 is provided with a vacuum gauge 35 to measure the degree of vacuum (pressure) in the vacuum chamber 30. The measured degree of vacuum is transmitted to the control circuit 38. The control circuit 38 controls the mass analyzer 101 based on the received degree of vacuum.

  The vacuum chamber 30 is provided with an inlet for introducing an ionized measurement sample (liquid) 18, and an orifice 3 is provided at the inlet. The hole diameter of the orifice 3 can be about φ0.1 mm to φ1 mm. An ion source 102 is connected to the orifice 3.

  The ion source 102 includes a dielectric container (dielectric partition wall) 1 and a high voltage application electrode 2. The dielectric container 1 is open at both ends and has a pipe shape. The opening at one end of the dielectric container 1 is connected to the vacuum chamber 30 with the orifice 3 interposed therebetween. The opening at the other end of the dielectric container 1 is connected to the slide valve container 6 of the slide valve 103 and is sealed by the slide valve 103. For this reason, the inside of the dielectric container 1 of the ion source 102 is differentially evacuated through the orifice 3 and depressurized.

  The high voltage application electrode 2 and the orifice 3 are arranged so that an AC voltage or a pulse voltage (rectangular waveform voltage) can be applied via the dielectric container 1, and between the high voltage application electrode 2 and the orifice 3. In this case, an AC voltage or a pulse voltage is applied by the barrier discharge AC power source 4 to generate a fluctuating electric field with the orifice 3 at a potential of 0 V, and the electric lines of force penetrate the dielectric container 1. The control circuit 38 performs control such as on / off of the AC voltage or the pulse voltage. Then, the charging of the electric charge inside the dielectric container 1 and the discharging to the orifice 3 are repeated in synchronization with the changing electric field by the application of the AC voltage or the pulse voltage. Plasma and thermoelectrons generated by the repetitively generated discharge ionize the gas 23 introduced into the ion source 102 of the dielectric container 1.

  The slide valve 103 includes a slide valve container 6, a slide valve valve body 7, a valve body shaft 8a, a vacuum bellows 8b, a guide roller 8c, a compression coil spring 8d, a first O ring 9a, a second O ring 9b, and a valve body O ring 9c. Have.

  The slide valve container 6 includes a through hole 6a that passes through the slide valve container 6, and a slide hole 6b that communicates with the through hole 6a from the outside of the slide valve container 6 so that the slide valve valve body 7 slides slidably. ,have. The slide valve container 6 is connected to the ion source 102 through the through hole 6a.

  The slide valve valve body 7 is opened when a thin tube 17a of a cartridge 104A described later is inserted into the slide valve container 6, and is closed when the thin tube 17a is extracted from the slide valve container 6.

  One end of the valve body shaft 8 a is connected to the slide valve valve body 7 and is inserted from the outside of the slide valve container 6. The vacuum bellows 8b allows the valve body shaft 8a outside the slide valve container 6 to move without causing vacuum deterioration. The guide roller 8c is attached to the other end of the valve body shaft 8a. The compression coil spring 8d is extrapolated to the valve body shaft 8a and urges the slide valve valve body 7 in the valve closing direction via the valve body shaft 8a.

  The guide roller 8 c is connected to a crank-shaped guide hole 180 a formed in the slider 180. The slider 180 is fixed to a Y-axis rear stage 140 described later, and is configured to operate the slide valve valve body 7 in the opening / closing direction in conjunction with the movement of the Y-axis rear stage 140 moving in the front-rear direction. Thus, the slide valve 103 does not operate electrically but operates mechanically. Therefore, power consumption can be reduced, and the mass spectrometer 100 can be reduced in size and weight.

  The first O-ring 9a is disposed upstream of the position where the slide valve valve body 7 of the through hole 6a of the slide valve container 6 seals the flow path. The second O-ring 9 b is disposed on the downstream side of the position where the flow path of the slide valve valve body 7 in the through hole 6 a of the slide valve container 6 is sealed. Thereby, the thin tube 17a is inserted into the through-hole 6a through the first O-ring 9a and the second O-ring 9b, so that the thin tube 17a and the ion source 102 can be hermetically connected. Conversely, the connection between the narrow tube 17a and the ion source 102 can be released by extracting the thin tube 17a from the through hole 6a (ion source 102) and closing the slide valve valve body 7. By this operation, the narrow tube 17a for introducing the sample gas to the ion source 102 can be inserted into or extracted from the ion source 102 while the ion source 102 is decompressed. Further, when the slide valve body 7 is closed by the valve body O-ring 9c, the airtightness of the through hole 6a on the ion source 102 side can be maintained.

  The cartridge 104A is detachable from the main body of the mass spectrometer 100 and is a disposable type. The measurement container cup 16A (measurement container) is filled with a measurement sample (liquid) 18 and sealed with a measurement container cap portion 15a (measurement container). )have. The head space 21 located at the upper part in the measurement container cup 16 is decompressed by the roughing pump 37 through the head space decompression pipe 17 connected to the measurement container cap part 15a. The pressure in the head space 21 is determined by the ratio between the amount of outside air (atmosphere) 47 flowing from the leak pipe 46 and the amount of gas 22 exhausted from the head space decompression pipe 17.

  In the cartridge 104A, when the head space 21 is depressurized or the measurement container is heated by the lower heater 110, the measurement sample (liquid) 18 is vaporized (gasified). That is, when the pressure of the head space 21 is lowered, the measurement sample (liquid) 18 is vaporized even at a low temperature. Conversely, when the pressure of the head space 21 is increased, the measurement sample (liquid) 18 is not vaporized unless the measurement sample (liquid) 18 is sufficiently heated. . In FIG. 1, the cartridge 104A that depressurizes the head space 21 is described as an example. However, the mass spectrometer 100 of the present embodiment can be applied to a cartridge that does not depressurize the head space 21, and The present invention can be applied not only to the liquid cartridge 104A (see FIGS. 2A and 2B) but also to the solid cartridge 104B (see FIGS. 3A and 3B).

  The gas 23 introduced into the ion source 102 of the vaporized measurement sample (liquid) 18 is sent from the sample gas pipe 17b connected to the measurement container cap portion 15a to the elastic tube 17c and the narrow tube every time the pinch valve 105 is opened and closed. It is intermittently introduced into the ion source 102 through 17a.

  The pinch valve 105 includes an elastic tube 17c sandwiched between a pinch valve tip 12, a pinch valve drive unit 13, and a measurement container cap unit 15a. The pinch valve tip 12 is driven by the pinch valve drive unit 13 controlled by the control circuit 38. As the pinch valve tip 12 rises, the elastic tube 17c is crushed and the valve is closed. Further, when the pinch valve tip 12 is lowered by the pinch valve drive unit 13, the pinch valve tip 12 is separated from the elastic tube 17c, and the valve is opened as a valve.

  Further, the pinch valve 105 can be opened and closed in a short time such that the valve opening time is approximately 200 msec or less. That is, the pinch valve 105 can perform the operation from the valve closing state to the valve closing state through the valve opening state in a short time of approximately 200 msec or less.

  When the pinch valve 105 is opened while the dielectric container 1 of the ion source 102 is differentially evacuated through the orifice 3, the measurement sample (vaporized in the head space 21 in the measurement container cup 16A ( The liquid 23 is introduced into the ion source 102 through the sample gas pipe 17b, the elastic tube 17c, and the thin tube 17a.

  At this time, the amount of the gas 23 introduced into the ion source 102, and the ultimate pressure in the dielectric container 1 that changes thereby, are the pressure of the reduced head space 21, the pressure of the vacuum chamber 30, the narrow tube 17a, It is determined by the conductance of the sample gas pipe 17b, the elastic tube 17c, and the orifice 3. On the other hand, the ultimate pressure in the vacuum chamber 30 changes with the opening time of the pinch valve 105. That is, if the pressure of the head space 21 is reduced or the conductance of the narrow tube 17a, the sample gas pipe 17b, and the elastic tube 17c is reduced, the amount of sample gas flowing in decreases, and the ultimate pressure in the dielectric container 1 decreases. Conversely, when the pressure in the head space 21 is increased or the conductance of the narrow tube 17a, the sample gas pipe 17b, and the elastic tube 17c is increased, the amount of sample gas that flows in increases, and the ultimate pressure in the dielectric container 1 increases. To do. Further, if the opening time of the pinch valve 105 is shortened, the amount of sample gas flowing in decreases, and the ultimate pressure in the vacuum chamber 30 decreases. Conversely, if the opening time of the pinch valve 105 is increased, the sample flowing in The amount of gas increases and the ultimate pressure in the vacuum chamber 30 increases.

  A part of the gas 23 introduced into the ion source 102 is ionized by plasma or thermoelectrons generated in the dielectric container 1 by applying an AC voltage or a pulse voltage to the high voltage application electrode 2.

  The ionization efficiency at this time depends on the density of plasma and thermionic electrons 5 generated by the barrier discharge. The density of plasma or thermionic electrons 5 is determined by the ultimate pressure in the dielectric container 1 and the voltage amplitude of the alternating voltage or pulse voltage applied to the high voltage application electrode 2.

  By optimizing the pressure in the head space 21 and the conductance of the narrow tube 17a, the sample gas pipe 17b, and the elastic tube 17c, the ultimate pressure in the dielectric container 1 can be sufficiently controlled.

  The pressure once increased in the dielectric container 1 can be lowered slowly with good reproducibility by differential exhaust using the orifice 3 after the pinch valve 105 is closed (see FIG. 10). For this reason, while the ultimate pressure in the dielectric container 1 and the pressure drop, the time belonging to the pressure band of 100 Pa to 20,000 Pa can be secured for a certain time with good reproducibility. Under this pressure range of 100 Pa to 20,000 Pa, dielectric barrier discharge can be generated with the atmosphere (air) as the main discharge gas. That is, by adjusting the time for opening the pinch valve 105, the time during which the inside of the dielectric container 1 belongs to the pressure zone of 100 Pa to 20,000 Pa can be controlled. Further, by adjusting the amplitude intensity, application time, and timing of the alternating voltage or pulse voltage applied to the high voltage application electrode 2 of the ion source 102, the time and timing for generating the dielectric barrier discharge, the generated plasma, and thermionic electrons. The intensity and amount of 5 can be adjusted. By these actions, the molecules of the sample gas to be subjected to mass spectrometry can be efficiently ionized depending on the purpose.

  Both the ionized sample gas (sample molecule ions) and the non-ionized sample gas (sample molecules) pass through the pores of the orifice 3 as the gas 24 introduced into the mass analysis unit 101, and the ion source 102. From the inside of the dielectric container (dielectric partition wall) 1, it flows into the vacuum chamber 30 of the mass spectrometer 101. In such a configuration, the distance from the ion source 102 to the mass analyzer 101 can be minimized, and the transmission loss of sample molecular ions can be minimized.

  Here, the flow rate per unit time of the gas flowing into the vacuum chamber 30 from the ion source 102 is the dielectric container when the gas 23 introduced into the ion source 102 flows into the dielectric container (dielectric partition wall) 1. It is determined by the ultimate pressure in the (dielectric partition wall) 1, the conductance (pore size) of the orifice 3, and the degree of vacuum (pressure) of the vacuum chamber 30. That is, when the difference between the ultimate pressure of the ion source 102 and the degree of vacuum of the vacuum chamber 30 is large, or the pores of the orifice 3 are large, the flow rate per unit time becomes large. When the difference between the pressure and the degree of vacuum in the vacuum chamber 30 is small, or the pores of the orifice 3 are small, the flow rate per unit time decreases.

  The flow rate per unit time of the gas flowing from the ion source 102 into the vacuum chamber 30 affects the change in the degree of vacuum (pressure) of the vacuum chamber 30. That is, when the flow rate per unit time is large, the pressure in the vacuum chamber 30 increases quickly, and conversely, when the flow rate per unit time is small, the pressure in the vacuum chamber 30 increases slowly. The ultimate pressure in the vacuum chamber 30 is determined by the total flow rate obtained by integrating the flow rate per unit time over time and the exhaust capacity of the turbo molecular pump 36.

  Sample molecule ions contained in the gas flowing from the ion source 102 into the vacuum chamber 30 are generated by the RF electric field and the DC electric field generated by the linear trap electrodes 31a, 31b, 31c, and 31d (see FIG. 1B) forming the quadrupole, A DC electric field formed by the cap electrode 32 and the end cap electrode 33 is trapped (ion accumulation) in the linear trap electrodes 31a, 31b, 31c, and 31d forming a quadrupole.

  On the other hand, non-ionized air or sample gas flowing from the ion source 102 into the vacuum chamber 30 is exhausted from the vacuum chamber 30 without being captured in the linear trap electrodes 31a, 31b, 31c, and 31d forming the quadrupole. Like the gas 26, the gas is exhausted from the vacuum chamber 30 through the turbo molecular pump 36 and the roughing pump 37.

  In order to efficiently transmit the sample molecular ions flowing into the vacuum chamber 30 into the linear trap electrodes 31a, 31b, 31c, 31d forming the quadrupole, the gap between the orifice 3 and the incap electrode 32, and the incap electrode 32 and a linear trap electrode 31a, 31b, 31c, 31d, an appropriate bias voltage is applied between the linear trap electrode 31a, 31b, 31c, 31d and the end cap electrode 33, and sample molecular ions are Accelerate in the direction of the linear trap electrodes 31a, 31b, 31c, and 31d forming the quadrupole of the mass spectrometer 101. For example, when the sample molecular ion to be measured is a positive ion, the orifice 3 is about -5V, the incap electrode 32 and the end cap electrode are about -10V, and the trap bias of the linear trap electrodes 31a, 31b, 31c, 31d is- About 20V can be applied. Further, by applying such a bias voltage, negative ions that are not measured can be prevented from entering the linear trap electrodes 31a, 31b, 31c, and 31d forming the quadrupole.

FIG. 1B is a configuration diagram of a mass analyzer of the mass spectrometer according to the embodiment of the present invention. FIG. 1B shows a cross-sectional view of a configuration in which the linear trap electrodes 31a, 31b, 31c, and 31d forming the quadrupole are viewed in the direction in which ions are introduced.
As shown in FIG. 1B, the linear trap that forms a quadrupole has four rod-shaped electrodes (linear ion trap electrodes) 31a, 31b, 31c, and 31d arranged concentrically. Different linear trap electrode AC voltages (trap RF voltages) 39a and 39b are applied to the pair of linear trap electrodes, respectively. It is known that the optimum value of the trap RF voltage varies depending on the electrode size and the measurement mass range. Typically, an RF voltage having an amplitude of 5 kV or less and a frequency of about 500 kHz to 5 MHz is applied. This trap RF voltage is applied, and a DC potential difference of several tens of volts is provided between the incap electrode 32 and the end cap electrode 33, thereby being surrounded by four linear ion trap electrodes 31a, 31b, 31c, and 31d. Ions such as sample molecular ions can be captured (ion accumulation) in the space.

  Before mass separation by the mass analysis unit 101, first, air and sample gas that has not been ionized and flows into the vacuum chamber 30 from the ion source 102 are sufficiently exhausted, and the pressure of the mass analysis unit 101 is changed to mass separation of ions. Must be reduced to 0.1 Pa or less. The total amount of gas flowing into the mass spectrometer 101 is equivalent to the amount of sample gas flowing into the ion source 102, and this amount of sample gas (the amount of molecules) is reduced in the headspace 21 of the measurement container cup 16 that has been decompressed. Since the gas is introduced for only a short time of several tens of ms to several hundreds of ms using the pinch valve 105, the mass analyzer 101 can be used even if the capacity of the turbo molecular pump 36 and the roughing pump 37 is small. The pressure can be lowered in a short time to a pressure of 0.1 Pa or less capable of mass spectrometry. Therefore, the mass spectrometer 100 can be reduced in size and weight. Further, since the pressure can be reduced in a short time, it is possible to increase the throughput when repeatedly performing mass spectrometry.

  When mass-separating ions captured by the mass analyzer 101, an AC voltage (auxiliary AC voltage) 39b for linear trap electrodes is applied between a pair of linear ion trap electrodes 31a and 31b facing each other. The auxiliary AC voltage is typically an AC voltage in which the amplitude is continuously changed at a single frequency of 50 V or less and a frequency of about 5 kHz to 2 MHz, or an AC voltage in which the frequency is continuously changed at a constant amplitude. Is used. By applying this auxiliary AC voltage, ions captured by the mass analysis unit 101 have a value obtained by dividing a specific mass number by the amount of charge according to a change in amplitude or frequency of the auxiliary AC voltage ( (Mass number / charge amount, m / z value) ions are continuously mass-separated and ejected in the direction of the mass-separated sample molecule ions 25 (see FIG. 1A), an electron multiplier, a multi-channel plate, Alternatively, it is converted into an electrical signal by an ion detector 34 (see FIG. 1A) composed of a conversion dynode, a scintillator, a photomultiplier, etc., and sent to the control circuit 38 to be stored (stored).

  FIG. 2A is a side view showing a cartridge (for liquid), and FIG. 2B is a cross-sectional view showing the cartridge (for liquid). First, the liquid structure of the liquid cartridge 104A and the solid cartridge 104B (see FIG. 3A) will be described.

  As shown in FIG. 2A, the cartridge 104A includes a body 15A, a measurement container cup 16A, and a nozzle 17A (introducing tube).

  The body 15A is configured by combining molded products made of resin (for example, polypropylene resin), and is formed in a substantially L shape in a side view. The body 15A includes a measurement container cap portion 15a to which the measurement container cup 16A is attached, a grip portion (grip) 15b to be gripped by hand, and holding portions 15c and 15d for holding the nozzle 17A.

  Further, a concave portion 15a1 with which the upper heater 120 (see FIG. 5A) abuts is formed on the side surface of the measurement container cap portion 15a. The recessed portion 15a1 is formed recessed toward the back side in the direction perpendicular to the paper surface of FIG. 2A.

  A sample gas pipe 17b extends forward from the front surface (side surface) of the recessed portion 15a1, which is a part of the measurement container cap portion 15a. The body 15A has a recessed portion 15a1 and an elastic tube in a side view. A notch 15a2 exposing a part of 17c is formed. Thus, the space formed by the recess 15a1 and the space exposing the elastic tube 17c are continuous in the front-rear direction.

  In the liquid cartridge 104A, the grip portion 15b has a function of gripping by hand, but the grip portion of the solid cartridge 104B described later has a function of gripping by hand and a vaporized measurement sample. It has both the function of generating an updraft. Therefore, although the grip portion 15b of the cartridge 104A is illustrated as a hollow structure, it may be a solid structure.

  The measurement container cup 16A is configured to be detachable from the body 15A. Further, the bottom surface 16h of the measurement container cup 16A is located below the lowermost surface 15t of the body 15A.

  The nozzle 17A has a thin tube 17a (PEEK tube, synthetic resin tube), a sample gas piping 17b (PEEK tube, synthetic resin tube), and an elastic tube 17c (silicon tube), in order from the front side. A thin tube 17a, an elastic tube 17c, and a sample gas pipe 17b are connected to form a single tube.

  As shown in FIG. 2B, in the measurement container cap portion 15a, a cylindrical threaded portion 15a3 that is screwed into the measurement container cup 16A protrudes downward from the lower surface of the rear portion of the body 15A. Moreover, the inside of the measurement container cap part 15a has a substantially dome-shaped space S.

  The holding portion 15c is located at the front end of the body 15A, and a through hole 15c1 penetrating in the front-rear direction is formed. The nozzle 17A is inserted through the through hole 15c1, and the narrow tube 17a of the nozzle 17A is held by the holding portion 15c via a fixed wedge 18a.

  The holding part 15d is located at the rear part of the body 15A, and is formed with a through hole 15d1 penetrating substantially in the front-rear direction. A nozzle 17A is inserted into the through hole 15d1, and the sample gas pipe 17b of the nozzle 17A is held by the holding portion 15d via a fixed wedge 18b. One end of the through hole 15d1 is formed in an L shape in cross section so as to communicate with the ceiling surface of the space S of the measurement container cap portion 15a.

  The holding portions 15c and 15d are formed so that the thin tube 17a and the sample gas pipe 17b are located on the same straight line. Further, the narrow tube 17a and the sample gas pipe 17b of the nozzle 17A are prevented from falling off from the body 15A by the fixed wedges 18a and 18b.

  A through hole 15f extending substantially in the front-rear direction is formed at the rear end of the body 15A. The through hole 15f is formed in an L shape in cross section, and one end of the through hole 15f is connected to the ceiling surface of the space S, and the other end communicates with the outside (atmosphere) of the body 15A. The through holes 15d1 and 15f are set to φ0.5 mm to 2 mm, for example.

  In addition, the body 15A is formed with a nozzle open space S2 that exposes the nozzle 17A downwardly between the holding portion 15c and the holding portion 15d. That is, the body 15A is provided with a nozzle open space S2 that allows access to the elastic tube 17c from below. Further, on the ceiling surface in the nozzle open space S2 (above the elastic tube 17c), a contact portion 15g capable of contacting the elastic tube 17c is formed.

  A protrusion 15h is formed on the upper surface of the body 15A. The protrusion 15h is for confirming the movement position when the cartridge 104A is set on the main body and moved to the measurable position.

  The measurement container cup 16A is made of a synthetic resin material and has a bottomed cylindrical shape. The measurement container cup 16A has a storage part 16a for storing a liquid sample in the lower part and a cylindrical threaded part 16b that is screwed into the screw part 15a3 of the measurement container cap part 15a in the upper part. .

  Further, in the measurement container cup 16A, the inner diameter of the screwing portion 16b is formed larger than the inner diameter of the storage portion 16a, and a step portion 16c is formed at the boundary between the screwing portion 16b and the storage portion 16a. On the upper surface of the stepped portion 16c, a concave portion 16d for accommodating the O-ring 16e is formed. When the measurement container cup 16A is screwed into the measurement container cap part 15a, the measurement container cup 16A is attached to the measurement container cap part 15a so as not to drop off. Further, by providing the O-ring 16e, the gap between the measurement container cup 16A and the measurement container cap portion 15a is sealed, so that the liquid sample in the measurement container cup 16A does not leak from the gap.

  The narrow tube 17a of the nozzle 17A is connected by being inserted into one end (front end) of the elastic tube 17c, and the sample gas pipe 17b is connected by being inserted into the other end (rear end) of the elastic tube 17c. . The abutting portion 15g corresponds to a portion composed only of the elastic tube 17c (a portion where the thin tube 17a is not fitted to the elastic tube 17c, a portion where the sample gas pipe 17b is not fitted to the elastic tube 17c). positioned.

3A is a side view showing the cartridge (for solid), FIG. 3B is a cross-sectional view showing the cartridge (for solid), FIG. 3C is a cross-sectional view taken along line AA of FIG. 3B, and FIG. It is process drawing which shows the adhesion procedure of a sample.
As shown in FIG. 3A, the cartridge 104B is detachable from the main body of the mass spectrometer 100 (see FIG. 1A), is a disposable type, and includes a body 15B, a measurement container cup 16B, and a nozzle 17B (introduction tube). . The nozzle 17B has the same configuration as the nozzle 17A.

  The body 15B is configured by combining molded products made of resin (for example, polypropylene resin), and is formed in a substantially L shape in a side view. The body 15B includes a measurement container cap 15i (measurement container) to which the measurement container cup 16B (measurement container) is attached, a gripping part (grip) 15b to be gripped by a hand, and holding parts 15c and 15d for holding the nozzle 17B. (See FIG. 3B).

  As shown in FIG. 3B, the grip portion 15b of the body 15B has a space S10 extending in the vertical direction inside, and a plurality of vent holes 15b1 communicating with the outside of the grip portion 15b on the side surface are spaced apart in the vertical direction. Is formed. Note that the shape, number, arrangement, and the like of the vent hole 15b1 are not limited to the present embodiment as long as the sample gas can be exhausted.

  The measurement container cap portion 15i of the body 15B has a cylindrical threaded portion 15i1 that is screwed into the measurement container cup 16B and projects downward from the lower surface of the rear portion of the body 15B.

  In addition, the body 15B is formed with a communication space S11 that communicates the substantially cylindrical space S of the measurement container cap portion 15i with the space S10 of the grip portion 15b. The communication space S11 and the space S10 form a space described in the claims.

  The holding part 15c holds the narrow tube 17a of the nozzle 17B via the fixed wedge 18a, similarly to the body 15A.

  The holding part 15d holds the sample gas pipe 17b of the nozzle 17B via a fixed wedge 18b. An end of the through hole 15d2 (corresponding to the through hole 15d1) formed in the holding portion 15d on the side opposite to the nozzle open space S2 communicates with the communication space S11. Further, the end portion of the sample gas pipe 17b is disposed so as to protrude into the communication space S11. Furthermore, the position of the end portion of the sample gas pipe 17b is arranged immediately above the pin 16f2 of the heating probe 16f, or the tip (upper end) of the pin 16f2 is brought close to the end portion of the sample gas pipe 17b, thereby heating the probe 16f. The sample gas heated and vaporized (sublimated) can be efficiently sucked.

  The measurement container cup 16B includes a heating probe 16f and a cup portion 16g.

  The heating probe 16f attaches a solid sample (including a solid produced by drying a liquid sample), and is formed of a metal material (for example, an aluminum alloy) with good thermal conductivity.

  The heating probe 16f is formed in a substantially T shape in cross section and has a support plate 16f1 having a disk shape and a pin 16f2 protruding upward from the radial center of the support plate 16f1.

  A concave portion 16f3 is formed at the tip (upper end) of the pin 16f2 for facilitating adhesion and holding of the solid sample. Further, the tip of the pin 16f2 protrudes from the cup portion 16g into the screwing portion 15i1 of the measurement container cap portion 15i.

  On the lower surface of the support plate 16f1, a ring portion 16f4 protruding downward along the peripheral edge portion is formed.

  The cup portion 16g has a substantially cylindrical shape, and a reduced diameter portion 16g1 is formed at the lower end portion. A circular opening 16g2 penetrating in the axial direction (vertical direction) of the pin 16f2 is formed on the bottom surface of the cup portion 16g. The ring portion 16f4 of the heating probe 16f is in contact with the upper surface (inner surface) of the reduced diameter portion 16g1. Therefore, the heating probe 16f does not pass through the opening 16g2 of the cup portion 16g.

  Further, on the outer peripheral surface of the cup portion 16g, a first collar portion 16g3 and a second collar portion 16g4 are formed at intervals in the vertical direction (axial direction). Further, the cup portion 16g is formed with a screwing portion 16g5 which is screwed with the screwing portion 15i1 of the measurement container cap portion 15i on the upper portion of the first collar portion 16g3.

  The first collar portion 16g3 is formed (annularly) over the entire circumference of the cup portion 16g. Thus, when the cup portion 16g is screwed and attached to the measurement container cap portion 15i, the cup portion 16g is over-tightened by restricting screwing by contacting the end surface (lower end surface) of the screw portion 15i1. Is prevented.

  The second collar portion 16g4 is formed over the entire circumference (annularly) at a position spaced downward from the first collar portion 16g3. By providing the second collar portion 16g4, the position of the lower heater 110 in the height direction can be fixed when the cartridge 104B is attached to the mass spectrometer 100 (see FIG. 1A).

  As shown in FIG. 3C, the cup portion 16g has protrusions 16g6, 16g6, and 16g6 projecting toward the ring portion 16f4 (see FIG. 3B) at positions corresponding to the ring portion 16f4 (see FIG. 3B) in the circumferential direction. Are formed at equal intervals (every 120 °). The heating probe 16f is held by the cup 16g by the friction of the three protrusions 16g6. In addition, about the number and position of the projection part 16g6, it can change suitably.

  As shown in FIG. 3B, when the heating probe 16f is attached to the cup portion 16g, the heating probe 16f is inserted from the inner side (screwing portion 16g5 side) of the cup portion 16g, and the ring portion 16f4 is pushed into the opening portion 16g2 side. Thus, the ring portion 16f4 is pushed in while crushing the tip of each projection portion 16g6 (see FIG. 3C), and the three projection portions 16g6 (see FIG. 3C) are held in close contact with the ring portion 16f4.

  As shown in FIG. 3D, for example, when a solid sample is attached to the heating probe 16f, the heating probe 16f is held with the tip of the pin 16f2 facing downward, and the cup portion 16g is pinched with a finger to face the solid sample. Then press the tip of the pin 16f2.

  At this time, since the support plate 16f1 is supported by the three protrusions 16g6 (see FIG. 3C) of the cup portion 16g, even if the heating probe 16f is turned upside down, the heating probe 16f may fall off the cup portion 16g. Absent. Further, since the ring portion 16f4 of the support plate 16f1 is in contact with the reduced diameter portion 16g1 of the cup portion 16g, when the heating probe 16f is pressed against the solid sample, the heating probe 16f is removed from the opening portion 16g2 of the cup portion 16g. There is no escape.

  Furthermore, the fitting of the heating probe 16f and the cup portion 16g in the measurement container cup 16B will be described. By the way, since the cup part 16g is made of resin and the heating probe 16f is made of metal, the heating probe 16f can be held by the cup part 16g if the dimension of the cup part 16g is too small with respect to the dimension of the heating probe 16f. If the measuring container cup 16B is turned upside down, the heating probe 16f will fall off the cup portion 16g. Therefore, the protrusion 16g6 (see FIG. 6C) is formed by molding by so-called minus tolerance, and the heating probe 16f is cupped so that the tip of the protrusion 16g6 (see FIG. 6C) is crushed by the support plate 16f1 of the heating probe 16f. By attaching to the part 16g, the heating probe 16f can be securely fitted to the cup part 16g.

  Although details will be described later, a heater (lower heater 110, see FIG. 4A) needs to lift and lift (lift up) the heating probe 16f from the cup portion 16g during measurement. The heater (lower heater 110, see FIG. 4A) is urged by the suspension 155 (see FIG. 4B) in a direction to separate the heater (see the lower heater 110, FIG. 4A) from the cartridge 104A (see FIG. 2A). Yes. For this reason, if the frictional force between the heating probe 16f and the cup portion 16g is too large, the spring force of the suspension 155 (see FIG. 4B) is lost and the heater cannot be pushed up. Furthermore, when the measurement container cup 16B (see FIG. 3A) is turned upside down, the heating probe 16f must be prevented from falling off the cup portion 16g. Therefore, by attaching the heating probe 16f to the cup portion 16g by a minus cross as described above, a certain amount of force is required when attaching the heating probe 16f to the cup portion 16g. 110, see FIG. 4A), when the heating probe 16f is detached from the cup portion 16g, only the frictional resistance between the ring portion 16f4 of the heating probe 16f and the protruding portion 16g6 (see FIG. 3C) is obtained. , It does not require a larger force than when installing. Furthermore, by making the protrusion 16g6 slope in the direction of removing the heating probe 16f (draft angle), it is possible to reduce the resistance when removing the heating probe 16f than when attaching the heating probe 16f. Further, by forming the heating probe 16f from a light metal material such as an aluminum alloy, the heating probe 16f does not fall off the cup portion 16g when the measuring container cup 16B is turned upside down.

  Next, the operation mechanism of the lower heater 110 and the upper heater 120 will be described with reference to FIGS. 4A and 4B. In the mass spectrometer 100 of the present embodiment, after the cartridge 104A (see FIG. 2A) is placed (set) at a predetermined position, the cartridge 104A (see FIG. 2A) is placed in a predetermined direction (forward, direction of the slide valve 103). The lower heater 110 and the upper heater 120 are configured to move to a predetermined position (position in close contact with the cartridge 104A) of the cartridge 104A (see FIG. 2A).

4A is a side view showing a structure for supporting the upper heater and the lower heater, and FIG. 4B is a side view showing a detailed support structure for the lower heater. In FIG. 4A, illustration of the cartridge 104A is omitted.
As shown in FIG. 4A, the mass spectrometer 100 includes a base 130, a Y-axis rear stage 140, a Y-axis front stage 150, an X-axis stage 160, and the like. In the following description, the direction in which the cartridge 104A (see FIG. 2A) operates is described as the front-rear direction, and the direction perpendicular to the front-rear direction is described as the left-right direction. The Y axis corresponds to the front-rear direction, and the X axis corresponds to the left-right direction.

  On the base 130, a rail 131 extending in the front-rear direction is provided. A Y-axis rear stage 140 is supported on the rail 131 via a bearing 132 so as to be movable in the front-rear direction. Further, a Y-axis front stage 150 is supported on the rail 131 through a bearing 133 so as to be movable in the front-rear direction.

  On the Y-axis front stage 150, a rail 151 extending in the left-right direction (the direction perpendicular to the paper surface) is provided. An X-axis stage 160 is supported on the rail 151 through a bearing 152 so as to be movable in the left-right direction.

  An upper heater 120 is provided on the X-axis stage 160 side. In addition, a guide roller shaft 161 that extends downward in the vertical direction (base 130 side) is fixed to the X-axis stage 160. A guide roller 162 is provided at the tip (lower end) of the guide roller shaft 161, and the guide roller 162 is disposed in a guide hole 134 (cam groove, see FIG. 5A) formed in the base 130.

  A shaft 153 extending downward in the vertical direction is fixed to the Y-axis front stage 150. A heater base 111 is supported on the shaft 153 so as to be movable up and down. A lower heater 110 is provided on the heater base 111. A guide roller 112 having a shaft is provided on the side surface of the heater base 111.

  The lower heater 110 includes a ceramic heater (for example, 5 W) in a copper heater block, and has a cylindrical shape. The diameter of the lower heater 110 is shorter than the inner diameter of the ring portion 16f4 of the heating probe 16f (see FIG. 3B) of the cartridge 104B. Although not shown, the lower heater 110 is provided with a thermocouple and a thermal fuse, similar to the upper heater 120 described later, and these are connected to the control circuit 38 (see FIG. 1A) via wiring. Yes.

  A guide plate 171 in which a guide hole (cam groove) 170 is formed is fixed to the base 130 so as to hang down from the base 130. The guide hole 170 has an inclined portion 170a that extends obliquely forward and upward, and a straight portion 170b that extends forward in the horizontal direction from the upper end of the inclined portion 170a. A guide roller 112 provided on the heater base 111 is disposed in the guide hole 170. As a result, the Y-axis front stage 150 moves forward, so that the guide roller 112 rises while being guided by the inclined portion 170a of the guide hole 170, and the lower heater 110 rises.

  As shown in FIG. 4B, a suspension 155 is provided between the lower heater 110 and the heater base 111. With the suspension 155, the height can be adjusted so that the lower heater 110 is in close contact with the bottom of the measurement container cup 16A of the cartridge 104A or the lower heater guide 110a is in close contact with the second collar portion 16g4 of the cartridge 104B.

  A suspension 156 is provided between the Y-axis front stage 150 and the wall 200 fixed to the base 130 to bias the Y-axis front stage 150 rearward (Y-axis rear stage 140 side). The urging force of the suspension 156 urges the Y-axis front stage 150 backward. A suspension 156 may be provided behind the Y-axis front stage 150, and the Y-axis front stage 150 may be pulled from behind. In other words, the Y-axis front stage 150 moves forward while receiving the urging force of the suspension 156.

  FIG. 5A is a plan view (first state) showing a mass spectrometer (equipped with a liquid cartridge) according to an embodiment of the present invention, and FIG. 5B is a mass spectrometer (equipped with a liquid cartridge) according to an embodiment of the present invention. FIG. 5C is a side view showing the mass spectrometer (liquid cartridge mounted) according to the embodiment of the present invention (first state), and FIG. 5D is a side view of the pinch valve. FIG. The first state is an initial state when the cartridge 104A is attached to the main body of the mass spectrometer 100. In FIG. 5A, since the upper heater 120 is provided symmetrically with the cartridge 104A in between, only one upper heater 120 (left side toward the front) is illustrated and described, and the other upper heater is described. Omitted.

  As shown in FIG. 5A, the mass spectrometer 100 includes a storage box 172 that stores the cartridge 104A. FIG. 5A shows a state in which the nozzle 17A of the cartridge 104A and the recessed portion (spotted portion) 15a1 of the body 15A (see FIG. 2A) are clear. In addition, the small dotted circle on the front side shown superimposed on the cartridge 104A in FIG. 5A indicates the position of the lower heater 110 in the first state, and the dotted round circle on the rear side indicates the position of the measurement container cup 16A. ing.

  The storage box 172 is made of a synthetic resin (for example, PEEK material) for storing the cartridge 104A, and includes a side plate 172a positioned on the left side of the cartridge 104A, a front plate 172b positioned in the front, and a rear plate 172c positioned in the rear. And a bottom plate 172d (see FIG. 5B) located below. The entire upper side of the storage box 172 is open, and the cartridge 104A can be lowered from the upper side of the storage box 172 and placed. The bottom plate 172d (see FIG. 5B) has a structure that communicates with the lower side of the storage box 172 so as not to hinder the operation of the lower heater 110 and the operation of the pinch valve 105.

  A heater introduction hole 173 into which the upper heater 120 is introduced is formed in the side plate 172 a of the storage box 172. 5A shows a state when the heater introduction hole 173 is cut at a substantially center in the height direction (vertical direction). The position of the heater introduction hole 173 corresponds to the position of the recess 15a1 of the cartridge 104A and a part of the elastic tube 17c (upstream side where the sample gas flows through the pinch valve 105) when the cartridge 104A is set in the storage box 172. doing.

  The front plate 172b of the storage box 172 is formed with a concave notch 174 through which the nozzle 17A passes when the cartridge 104A is placed on the storage box 172.

  The upper heater 120 heats the upper part of the measurement container, that is, the portion where the vaporized measurement sample (liquid sample) stays, and has a substantially rectangular shape in plan view. Further, the upper heater 120 is configured, for example, by sandwiching a ceramic heater 120a (for example, 5 W) between copper heater blocks 120b. The ceramic heater 120a is connected to the control circuit 38 (see FIG. 1A) via wiring (not shown).

  The upper heater 120 has a quadrangular end face 120d that comes into surface contact with the recess 15a1. Further, a claw portion 120s (protrusion) extending forward from the end surface 120d is formed at the front end in the front-rear direction at the front end in the left-right direction of the upper heater 120. The claw 120s is also composed of a copper heater block and is heated by the ceramic heater 120a.

  The heater block 120b incorporates a thermocouple 120c for the thermometer side of the upper heater 120 in the vicinity of the ceramic heater 120a. The thermocouple 120c is also connected to the control circuit 38 (see FIG. 1A). The upper heater 120 is provided with a temperature fuse (not shown) for preventing abnormal heating.

  The upper heater 120 is screwed to a resin block 121 (resin member), and the resin block 121 is supported by a pair of arms 122 and 122. The arms 122 and 122 are screwed to the X-axis stage 160 so as to be detachable.

  A photosensor 154 is provided on the Y-axis front stage 150. The X-axis stage 160 is provided with a plate-shaped light shielding plate 163 extending in the left-right direction. The light shielding plate 163 extends to the photosensor 154 side and is supported by the X-axis stage 160 in a cantilever state. When the X-axis stage 160 moves from the first state to a predetermined position in the right direction (on the cartridge 104A side), light incident on the photosensor 154 is shielded by the light shielding plate 163. Thereby, it is determined by the control circuit 38 (see FIG. 1A) that the upper heater 120 has reached a specified position (measurement start position, heating start position).

  The resin block 121 is formed of, for example, a PEEK material. The PEEK material is a so-called engineering plastic, has high strength, is lightweight, and has good heat resistance (for example, 250 ° C. or higher).

  The pair of arms 122, 122 (metal member) is made of, for example, an aluminum alloy, extends from the X-axis stage 160 to the cartridge 104A side, and has a base end fixed to the X-axis stage 160 with screws. A compression coil spring 123 (biasing member) that biases the upper heater 120 in the direction of the cartridge 104A is provided between the resin block 121 to which the upper heater 120 is fixed and the X-axis stage 160.

  As shown in FIG. 5B, the claw portion 120s of the upper heater 120 is formed at the height position of the elastic tube 17c, and the upper half of the left side of the elastic tube 17c exposed when the end surface 120d is in close contact with the recess portion 15a1. It is formed in an arc shape so that it can be covered.

  The resin block 121 is formed in a substantially L shape when viewed from the front, and the upper heater 120 is screwed to the upper surface of the extending portion 121a extending to the right side. Further, shaft portions 121b and 121c are formed on the side surface of the resin block 121 with a space therebetween. Note that shaft portions 121b and 121c are formed on the opposite side surface of the resin block 121 in the same manner.

  A U-shaped cutout groove 122a in which the shaft portion 121b slides so as to be movable in the left-right direction and a long hole 122b in which the shaft portion 121c slides so as to be movable in the left-right direction are formed in the tip portion of the arm 122. Yes. In the first state, the shaft portions 121b and 121c are positioned so as to be positioned away from the left end of the notch groove 122a and separated from the left end of the long hole 122b.

  Thus, the metal (the upper heater 120 made of copper) is supported by the resin (the resin block 121), and the resin (the resin block 121) is supported by the metal (the stainless steel arm 122). The resin (resin block 121) is pivotally supported by metal (stainless steel arm 122). Resin (resin block 121) is supported by the X-axis stage 160 via a compression coil spring 123. Therefore, since the heat transfer path from the upper heater 120 is limited, it becomes difficult for the heat of the upper heater 120 to diffuse to the side supporting the upper heater 120, and as a result, power consumption can be suppressed.

  Further, a guide hole (cam groove) 134 for guiding the guide roller 162 of the guide roller shaft 161 fixed to the X-axis stage 160 is formed in the base 130. The guide hole 134 has an inclined portion 134a (see FIG. 5A) that extends obliquely forward to the right and a straight portion 134b (see FIG. 5A) that extends forward at the front end of the inclined portion 134a.

  Accordingly, the Y-axis front stage 150 (see FIG. 5A) moves forward, whereby the guide roller 162 is guided along the inclined portion 134a (see FIG. 5A) of the guide hole 134, and the upper heater 120 is moved to the right side (cartridge). 104A side).

  As shown in FIG. 5C, the Y-axis rear stage 140 is provided with a pinch valve tip 12, and the base 130 is provided with a pinch valve drive unit 13. As described above, the pinch valve 105 (see FIG. 1A) is provided with the valve element side (pinch valve tip 12) of the pinch valve 105 (see FIG. 1A) and the pinch valve driving unit 13 separately.

  On the valve element side of the pinch valve 105 (see FIG. 1A), a pinch valve tip 12 that presses against the elastic tube 17c of the cartridge 104A and closes, a compression coil spring 181 that biases the pinch valve tip 12 upward, And a connecting plate 182 extending vertically downward from the pinch valve tip 12. The connection plate 182 is formed with a connection hole 183 connected to the connection pin 137 of the pinch valve driving unit 13.

  On the other hand, the pinch valve drive unit 13 is of an electromagnetic operation type and is fixed on a pinch valve base 135 fixed to the base 130. The pinch valve drive unit 13 includes a drive unit 136 and a connecting pin 137.

  The distal end (upper end) of the connecting pin 137 is bent and formed in an L shape in a side view toward the connecting hole 183 side. The connection pin 137 is provided in the drive unit 136 when the electromagnetic coil in the drive unit 136 is energized (excited), the connection pin 137 is lowered, and the electromagnetic coil is de-energized. By urging upward with a spring (not shown), the connecting pin 137 returns to the initial state. Therefore, since electric power is consumed only when the pinch valve 105 (see FIG. 1A) is opened, it is possible to save power, and the mass spectrometer 100 can be reduced in size and weight.

  As shown in FIG. 5D, a connecting plate 182 extends integrally with the pinch valve tip 12 downward in the vertical direction. The connecting plate 182 passes through the Y-axis rear stage 140 downward. In addition, a pair of flange portions 182 a and 182 a are formed on the connecting plate 182 above the Y-axis rear stage 140. A compression coil spring 181 is interposed between the collar portion 182a and the Y-axis rear stage 140 to urge the pinch valve tip 12 upward.

  The state shown in FIGS. 4A and 5A to 5C is the first state. That is, the first state is a state (initial position) when the cartridge 104A (see FIGS. 5A to 5C) is placed on the mass spectrometer 100, and the Y-axis rear stage 140 and the Y-axis front stage 150 are moved back and forth. Further, the Y-axis front stage 150 is spaced rearward from the wall 200 that separates the slide valve 103 (see FIG. 4A) and the cartridge 104A.

FIG. 6A is a plan view (second state) showing a mass spectrometer (equipped with a liquid measurement container) according to an embodiment of the present invention, and FIG. 6B is a mass spectrometer (for liquid) according to an embodiment of the present invention. It is a side view (2nd state) which shows the measurement container of (2).
As shown in FIG. 6A, after the cartridge 104A is set in the storage box 172 (see FIG. 5A), for example, when the cartridge 104A is moved forward (pressed), the Y-axis rear stage 140 moves forward together with the cartridge 104A. Then, the front surface of the Y-axis rear stage 140 contacts the Y-axis front stage 150. This contacted state is the second state.

  When the second state shown in FIG. 6A is reached, the positions of the upper heater 120 and the heater introduction hole 173 in the front-rear direction match. That is, the position of the end surface 120d of the upper heater 120, the position of the recess 15a1 of the cartridge 104A, and the position of a part of the elastic tube 17c face each other.

  Further, the Y-axis rear stage 140 moves forward, whereby the cartridge 104A housed in the housing box 172 moves forward, and the thin tube 17a is inserted into the slide valve 103 (see FIG. 1A) and the slide valve 103 (FIG. 1A). Open).

  As shown in FIG. 6B, when the Y-axis rear stage 140 comes into contact with the Y-axis front stage 150, the positions of the measurement container cup 16A and the lower heater 110 in the front-rear direction match (see double broken lines).

  As described above, the upper heater 120 is supported by the Y-axis front stage 150 as shown in FIG. 6A. Therefore, in the process from the first state shown in FIG. 5A to the second state shown in FIG. The front stage 150 does not move. Therefore, the guide roller 162 that guides the upper heater 120 does not move and remains positioned at the rear end of the inclined portion 134 a of the guide hole 134. In the process from the first state shown in FIG. 5C to the second state shown in FIG. 6B, the guide roller 112 for guiding the lower heater 110 does not move as shown in FIG. 6B, and the inclined portion 170a of the guide hole 170 is moved. It remains in the lower end.

  Further, in the second state shown in FIG. 6B, the valve element side (pinch valve tip 12) of the pinch valve 105 (see FIG. 1A) is not connected to the pinch valve drive unit 13. Therefore, in the second state, the pinch valve tip 12 pushes up the elastic tube 17c by the biasing force of the compression coil spring 181 and the pinch valve 105 (see FIG. 1A) is in a closed state.

FIG. 7A is a plan view (third state) showing a mass spectrometer (equipped with a liquid measurement container) according to an embodiment of the present invention, and FIG. 7B is a mass spectrometer (for liquid) according to an embodiment of the present invention. FIG. 7C is a side view showing the mass spectrometer (equipped with a liquid measurement container) according to the embodiment of the present invention. .
When the Y-axis rear stage 140 is further moved forward (in the direction of the arrow) in a state where it is docked with the Y-axis front stage 150, the Y-axis rear stage 140 and the Y-axis front stage 150 are moved forward together. The third state shown in FIGS. 7A to 7C is reached. At this time, in the process from the second state shown in FIG. 6A to the third state shown in FIG. 7A, the relative positions in the front-rear direction of the upper heater 120 and the heater introduction hole 173 move forward without changing. In the process from the second state shown in FIG. 6B to the third state shown in FIG. 7C, the relative positions of the lower heater 110 and the measurement container cup 16A in the front-rear direction move forward without changing.

  In the process from the second state shown in FIG. 6A to the third state shown in FIG. 7A, the guide roller 162 is guided by the inclined portion 134a of the guide hole 134 and the upper heater 120 faces the heater introduction hole 173. Moving. When the guide roller 162 reaches the front end of the inclined portion 134a of the guide hole 134, the end surface 120d of the upper heater 120 comes into close contact with the recessed portion 15a1 of the cartridge 104A.

  Thus, by dividing into two stages, the Y-axis rear stage 140 and the Y-axis front stage 150, the upper heater 120 and the heater introduction hole 173 can be moved forward without changing the relative positions. 120 can be easily introduced into the heater introduction hole 173, and similarly, the lower heater 110 can be advanced without changing the relative position between the lower heater 110 and the measurement container cup 16A. It can be easily adhered to the bottom surface 16h (see FIG. 2A) of the cup 16A.

  By the way, a difference in heat conductivity occurs depending on how the cartridge 104A and the upper heater 120 are in contact with each other. For example, in point contact or line contact, the thermal resistance increases and the temperature does not increase easily. Therefore, in the present embodiment, the upper heater 120 is brought into close contact with the recess 15a1 of the cartridge 104A through the compression coil spring 123 (suspension) so that the head space 21 of the cartridge 104A (see FIG. 1A) can be obtained in a short time. Can be heated. Thereby, power consumption can be suppressed, a reduction in size and weight can be realized, and a portable mass spectrometer 100 can be realized.

  Further, if the lower heater 110 is not in close contact with the bottom surface 16h (see FIG. 2A) of the measurement container cup 16A, the heat capacity of the lower heater 110 is increased, and the power consumption is increased. However, in the present embodiment, the lower heater 110 is brought into close contact with the measurement container cup 16A via the suspension 155 (see FIG. 4B), so that power consumption can be reduced, and the size and weight reduction and the portable mass spectrometer 100 can be realized. Can be realized.

  When the guide roller 162 reaches the front end of the inclined portion 134a of the guide hole 134, the light shielding plate 163 blocks light from entering the photosensor 154, so that the upper heater 120 is controlled by the control circuit 38 (see FIG. 1A). Can be determined to have reached a specified position (position in close contact with the recess 15a1). As described above, by detecting that the upper heater 120 has reached the specified position, an abnormal operation of the upper heater 120 can be detected.

  Further, as shown in FIG. 7B, when the guide roller 162 reaches the front end of the inclined portion 134a (see FIG. 7A) of the guide hole 134, the upper heater 120 fixed to the resin block 121 applies the biasing force of the compression coil spring 123. In response, the shaft portion 121b of the resin block 121 moves in the notch groove 122a, and the shaft portion 121c moves in the elongated hole 122b, whereby the end surface 120d of the upper heater 120 can be brought into close contact with the recessed portion 15a1.

  By the way, when the measurement sample (liquid or solid) is heated and the high temperature sample gas rises, the inner surface of the measurement container cap portion 15a of the body 15A of the cartridge 104A and the sample gas pipe 17b of the cartridge 104B become cold spots. The sample gas may be adsorbed or moisture may be condensed, resulting in insensitivity (decrease in performance). In addition, condensation may cause the liquid to enter the ion source 102 or the vacuum chamber 30 and hinder the pumping operation of the vacuum pump. Therefore, in the present embodiment, an upper heater 120 is provided to heat a portion where the sample gas (vaporized measurement sample) including the upper portion of the measurement container cup 16A stays, thereby preventing condensation and improving sensitivity (performance). Up).

  Further, the claw portion 120s of the upper heater 120 covers half of the portion where the elastic tube 17c between the recessed portion 15a1 and the pinch valve 105 (see FIG. 1A) is exposed. 7B shows a state in which the claw portion 120s is in contact with the elastic tube 17c, the claw portion 120s may be arranged in a state of being separated from the elastic tube 17c. By the way, only the upstream side of the pinch valve 105 (see FIG. 1A) of the elastic tube 17c is heated by the claw portion 120s, the sample gas may stay on the upstream side of the pinch valve 105 of the elastic tube 17c. Since the downstream side (decompression side) of the pinch valve 105 of the elastic tube 17c is decompressed and adiabatically expanded, it is difficult to condense and the sample gas is introduced at a high speed when the pinch valve 105 is opened. This is because condensation and adsorption are difficult.

  The guide roller 162 moves from the inclined portion 134a (see FIG. 7A) of the guide hole 134 to the linear portion 134b (see FIG. 7A) while maintaining the state in which the upper heater 120 is in close contact with the predetermined position of the cartridge 104A. Finally, the guide roller 162 is positioned by the straight portion 134b.

  Since the Y-axis front stage 150 (see FIG. 4A) is urged by the suspension 156 (see FIG. 4A) to return to the second state (backward), the upper heater 120 on the X-axis stage 160 is also suspended. A return force (biasing force) for returning to the second state is applied by the urging force (elastic return force) of 156 (see FIG. 4A). Incidentally, in the third state, if the guide roller 162 is to be positioned by the inclined portion 134a (see FIG. 7A), the upper heater 120 returns to the second state due to the elastic return force of the suspension 156. However, in the present embodiment, the guide roller 162 is positioned by the straight portion 134b, so that even if a return force F1 (see FIG. 7A) by the suspension 156 acts on the guide roller 162, the guide roller 162 is guided by the straight portion 134b. Movement (return) can be regulated (backlash can be prevented).

  In addition, when the upper heater 120 is positioned by the inclined portion 134a (see FIG. 7A), the position of the upper heater 120 in the left-right direction changes depending on the position of the inclined portion 134a. However, in this embodiment, since the upper heater 120 is positioned by the linear portion 134b (see FIG. 7A), the position of the upper heater 120 in the left-right direction does not change even if the position of the cartridge 104A slightly moves back and forth. Absent. That is, by positioning the upper heater 120 with the straight portion 134b, the position of the upper heater 120 in the left-right direction is determined with mechanical accuracy.

  In the process from the second state shown in FIG. 6B to the third state shown in FIG. 7C, the guide roller 112 moves up the inclined portion 170 a of the guide hole 170, and the lower heater 110 moves up together with the heater base 111. When the guide roller 112 reaches the upper end of the inclined portion 170a, the lower heater 110 comes into close contact with the bottom of the measuring container cup 16A of the cartridge 104A or the lower heater guide 110a comes into contact with the second collar portion 16g4 of the cartridge 104B.

  Thus, by dividing into two stages, the Y-axis rear stage 140 and the Y-axis front stage 150, the lower heater 110 can be easily brought into contact with the bottom surface 16h of the measurement container cup 16A.

  And the guide roller 112 moves the linear part 170b from the inclined part 170a of the guide hole 170, maintaining the state which the lower heater 110 contact | adhered to the bottom face 16h of the measurement container cup 16A. Finally, the guide roller 112 is positioned by the straight portion 170b.

  When the heater base 111 is positioned in the third state and the guide roller 112 is positioned by the inclined portion 170a, the lower heater 110 returns to the second state in response to the elastic restoring force of the suspension 155. However, in this embodiment, even if the return force F2 (see FIG. 7C) due to the suspension 155 (see FIG. 4B) acts on the guide roller 112 by positioning the guide roller 112 with the straight portion 170b, the straight portion The movement (return) of the guide roller 112 can be restricted by 170b.

  Further, when the lower heater 110 is to be positioned by the inclined portion 170a, the vertical position of the lower heater 110 changes depending on the position of the inclined portion 170a. However, in the present embodiment, since the lower heater 110 is positioned by the linear portion 170b, the vertical position of the lower heater 110 does not change even if the position of the cartridge 104A slightly changes. That is, by positioning the lower heater 110 with the linear portion 170b, the vertical position of the lower heater 110 is determined with mechanical accuracy.

  On the other hand, in the second state (see FIG. 6B) in which the Y-axis rear stage 140 is in contact with (docked) the Y-axis front stage 150, the connecting plate 182 of the pinch valve 105 (see FIG. 1A) It is separated. In this state, the pinch valve tip 12 is pushed up by the urging force of the compression coil spring 181, and the elastic tube 17 c of the nozzle 17 </ b> A is crushed by the pinch valve tip 12, thereby closing the valve. The same applies to the first state (see FIG. 5C).

  Then, when the Y-axis rear stage 140 and the Y-axis front stage 150 integrally move to the third state (see FIG. 7C), the connecting plate 182 is connected to the pinch valve driving unit 13. That is, the connection pin 137 of the pinch valve drive unit 13 is inserted into the connection hole 183 formed in the connection plate 182.

  As described above, the pinch valve drive unit 13 is fixed to the base 130 side, and the pinch valve drive unit 13 and the valve body side (pinch valve tip 12) of the pinch valve 105 (see FIG. 1A) are separated. When the cartridge 104A is moved from the first state to the third state through the second state, the load due to the weight of the pinch valve driving unit 13 can be reduced.

  When the sample gas is charged, the drive unit 136 is energized by the control circuit 38 (see FIG. 1A), whereby the connecting pin 137 is pulled down, and the pinch valve tip 12 is pulled down against the urging force of the compression coil spring 181. The pinch valve 105 (see FIG. 1A) is opened. When the control circuit 38 is deenergized, the connecting pin 137 is pushed back by the spring force (not shown) in the drive unit 136, and the pinch valve tip 12 is elastically received by the urging force of the compression coil spring 181. The tube 17c is crushed and the valve is closed.

  By the way, when the mass spectrometer 100 is reduced in size and weight, heaters cannot be installed in various places. Thus, in the present embodiment, by locally providing a heater that heats the measurement sample, such as the lower heater 110 and the upper heater 120, the power required to operate the mass spectrometer 100 can be reduced, thereby saving power. By miniaturization, it is possible to realize a small size and light weight. Further, by providing the upper heater 120 that heats the vaporized measurement sample (sample gas), dew condensation can be prevented and sensitivity can be improved (performance can be improved), thereby providing a highly accurate mass spectrometer.

  FIG. 8A is a side view (first state) showing a mass spectrometer (equipped with a measurement container for solids) according to an embodiment of the present invention, and FIG. 8B is a mass spectrometer (for solids) according to an embodiment of the present invention. FIG. 8C is a side view (third state) showing the mass spectrometer (equipped with a solid measurement container) according to the embodiment of the present invention. . The liquid cartridge 104 </ b> A and the solid cartridge 104 </ b> B (sample introduction unit) are performed by the common mass spectrometer 100. The open / close valve 45 (see FIG. 1A) is closed.

  As shown in FIG. 8A, in the first state, similarly to the case of the liquid cartridge 104A, the Y-axis rear stage 140 is separated rearward from the Y-axis front stage 150, and the measurement container cup 16B is disposed behind the lower heater 110. Is located.

  8A (first state) to FIG. 8B (second state), that is, when the Y-axis rear stage 140 moves forward and contacts the Y-axis front stage 150, the measurement container cup 16B is directly below. The lower heater 110 is located.

  Then, from FIG. 8B (second state) to FIG. 8C (third state), that is, when the Y-axis rear stage 140 and the Y-axis front stage 150 integrally move forward and come into contact with the wall 200. The heating probe 16f is lifted (lifted up) by the lower heater 110, and the heating probe 16f is put on the lower heater 110. At this time, since the diameter of the lower heater 110 is shorter than the diameter of the opening 16g2 of the cup portion 16g, a gap T1 is formed between the lower heater 110 and the opening 16g2. Further, since the support plate 16f1 of the heating probe 16f is supported by the protrusion 16g6 (see FIG. 3C) of the cup portion 16g, the clearance T2 is formed between the support plate 16f1 and the inner peripheral wall surface of the cup portion 16g by lift-up. Is formed. By forming the gaps T1 and T2 in this way, a flow path in which air rises is formed as shown by arrows in FIG. 8C.

  By doing so, not only can the heat of the lower heater 110 be efficiently transmitted to the heating probe 16f, but neither the lower heater 110 nor the heating probe 16f is in contact with the measurement container cup 16B. Even if it is necessary to set the temperature to 150 ° C. to 200 ° C., the measurement container cup 16B can be made of resin, and the cost of the cartridge 104B can be reduced.

  By the way, when the measurement sample (solid sample) is heated, many gases (excess gas) of various components come out from the measurement sample, and such extra gas needs to be discharged from the cartridge 104B. Therefore, as described above, the cartridge 104B has a chimney structure, so that an updraft is generated and fresh air can be taken in, so that highly accurate mass spectrometry can be performed.

  Depending on the type of measurement sample, there may be a strange odor (strong odor) generated by heating, so a plate-like adsorbent (such as an activated carbon filter) is placed in the space S10 of the grip portion 15b (chimney portion) of the cartridge 104B. May be arranged so as not to obstruct the air flow to reduce odor components.

FIG. 9 is a flowchart of a mass spectrometry method performed by the mass spectrometer 100 according to the first embodiment of the present invention. Hereinafter, a case where the measurement sample is a liquid will be described.
First, when the mass spectrometer 100 is turned on by the operator, the mass spectrometer 100 (control circuit 38) is activated. In step S1 shown in FIG. 9, the control circuit 38 automatically evacuates the vacuum chamber 30 by the control using the turbo molecular pump 36, the roughing pump 37, the vacuum gauge 35, and the like. The control circuit 38 monitors the degree of vacuum (change) in the vacuum chamber 30 with the vacuum gauge 35 and determines whether or not the degree of vacuum in the vacuum chamber 30 has reached a prescribed degree of vacuum. After determining that the specified degree of vacuum has been reached, the process proceeds to step 2.

  In step S2, the operator removes the measurement container cup 16A from the cartridge 104A and puts the measurement sample 18 (liquid) into the measurement container cup 16A as shown in FIG. 2B. The operator attaches the measurement container cup 16A to the cartridge 104A. As shown in FIGS. 5A to 5C, the operator attaches (sets) the cartridge 104A to the main body (the main body of the mass spectrometer 100).

  By setting the cartridge 104A in the main body, the elastic tube 17c is crushed by the pinch valve 105 (pinch valve tip 12), the flow path is closed, and the pinch valve 105 is in a closed state. This closed state of the pinch valve 105 continues until the end of step S7. When the cartridge 104A is set in the main body, the head space decompression pipe (decompression unit) 17 is connected to the cartridge 104A via the communication hole 15f. In the plan view (second state) shown in FIG. 6A to the plan view (third state) shown in FIG. 7A, the cartridge 104A is prevented from being lifted by the urging force that crushes the elastic tube 17c by the pinch valve 105. The guide roller (not shown) presses the cartridge 104A from above.

  Whether the cartridge 104A is for depressurization measurement (for liquid), atmospheric pressure measurement (for liquid), or atmospheric pressure measurement (for solid), the cartridges 104A and 104B are set in the main body. In this case, the difference between the shapes of the cartridges 104A and 104B can be realized by a sensor (not shown) connected to the control circuit. When the decompression measurement cartridge 104A is set in the main body, the control circuit 38 opens the opening / closing valve 45 in step S6.

  In step S3, as shown in FIG. 5A (first state) to FIG. 6A (second state), the operator grasps the grip portion 15b of the cartridge 104A and moves the Y-axis rear stage 140 on which the cartridge 104A is set. The Y-axis rear stage 140 is brought into contact with the Y-axis front stage 150 while being moved in the direction of the slide valve 103 (forward). During this time, the pinch valve 105 remains closed.

  In step S4, after the narrow tube 17a of the nozzle 17A has penetrated the first O-ring 9a, the slide valve valve body 7 moves in the direction of coming out of the slide valve container 6, and the slide valve 103 is opened. The thin tube 17a of the nozzle 17A penetrates the second O-ring 9b, and the tip of the thin tube 17a is inserted into the dielectric container 1.

  In step S5, the operator moves the cartridge 104A in a state where the Y-axis rear stage 140 and the Y-axis front stage 150 are docked, as shown in the change from FIG. 6A (second state) to FIG. 7A (third state). It is further moved in the direction (forward) of the slide valve 103. As a result, the lower heater 110 is in close contact with the bottom surface 16h of the measurement container cup 16A, and the upper heater 120 is in close contact with the recess 15a1 formed in the upper part of the measurement container cup 16A. The movement of the lower heater 110 and the upper heater 120 to this position is determined by blocking light incident on the photosensor 154 by the light shielding plate 163.

  The control circuit 38 determines whether or not the cartridge 104 </ b> A has moved to a predetermined position that can be measured by the photo sensor 154. The operator moves the cartridge 104A until the protruding portion 15h of the cartridge 104A matches the mark (marking, groove, etc.) on the main body side. If the control circuit 38 determines that the photosensor 154 has not moved to the specified position, the control circuit 38 prompts the operator to further move the cartridge 104A. If the control circuit 38 determines that the photosensor 154 has moved to the specified position, To stop moving.

  In step S <b> 6, the control circuit 38 decompresses the head space 21 in the sample container (measurement container cup 16 </ b> A + measurement container cap portion 15 a) via the head space decompression pipe (decompression unit) 17.

  In step S7, the control circuit 38 monitors the degree of vacuum (change) in the vacuum chamber 30 with the vacuum gauge 35, and whether the degree of vacuum once lowered in step S4 recovers and rises, is it equal to or higher than a specified value. Determine whether or not. When the degree of vacuum in the vacuum chamber 30 is not less than the specified value, the process proceeds to step S8. If it is less than the specified value, an error is generated and the process does not proceed to step S8. In this case, since it is considered that there is a problem in the insertion of the thin tube 17a, the flow returns to step S3 or returns to step S2, and the thin tube 17a is inserted again.

  In step S8, the control circuit 38 energizes the drive unit 136 and pulls the connection pin 137 to start the measurement, thereby pulling down the connection plate 182 and opening the pinch valve 105 (elastic tube 17c). A sample gas is introduced into the ion source 102 (inside the dielectric container 1).

  By the way, if the operation of opening the slide valve 103 and the operation of moving the lower heater 110 and the upper heater 120 are performed simultaneously in one operation, the resistance load becomes very large and the cartridge 104A may be damaged. . However, such a malfunction can be prevented by operating the Y-axis rear stage 140 and the Y-axis front stage 150 separately in two.

  In addition, electrical components are mounted on the lower heater 110 and the upper heater 120, and when the lower heater 110 and the upper heater 120 operate, cables connected to the lower heater 110 and the upper heater 120 move correspondingly. Become. Thereby, there exists a possibility that a cable may become obstructive or a cable may be disconnected by stress. Therefore, in this embodiment, the slide valve 103 is opened by the operation from the first state to the second state, and the lower heater 110 and the upper heater 120 are operated by the operation from the second state to the third state. The moving distance of 110, 120 can be shortened, and disconnection of the cable can be suppressed.

FIG. 10 shows the fluctuation of the pressure (b) in the ion source 102 (in the dielectric container 1) and the fluctuation in the pressure (c) in the vacuum chamber 30 as the pinch valve 105 is opened and closed (a).
As shown in FIGS. 10A and 10B, when the pinch valve 105 is opened, the pressure in the dielectric container 1 increases, and the atmosphere is used as the discharge gas in several tens of milliseconds with good reproducibility. In this case, the pressure (for example, 100 to 20,000 Pa, preferably 5000 to 10,000 Pa, 9,000 Pa in the example of FIG. 10B) suitable for ionization of the barrier discharge method is reached. As shown in FIG. 10C, the pressure in the vacuum chamber 30 gradually increases to about 20 to 100 Pa in conjunction with the increase in the pressure in the dielectric container 1 due to differential evacuation.

In step S9, the control circuit 38 generates barrier discharge in the dielectric container 1, and starts ionization of the sample gas. Optimal ionization is realized by starting and ending the barrier discharge in synchronization with the fluctuation of the pressure in the dielectric container 1. As shown in FIG. 10A, when the pinch valve 105 is opened for a short time of 30 ms to 100 ms, as shown in FIG. 10B, the pressure in the dielectric container 1 is ionized by the barrier discharge method. The pressure range suitable for the pressure range is 100 to 20,000 Pa, preferably 5,000 to 10,000 Pa. The time during which the pressure in the dielectric container 1 is in this pressure zone is a time zone (50 ms to 1 s) suitable for the ionization of the barrier discharge method, and if it is within this time zone, the barrier discharge can be easily performed. Can be generated. Note that the time period suitable for ionization of the barrier discharge method is longer than the time required for ionization of reaction ions (ionization execution time) necessary for securing sufficient sample molecular ions by mass spectrometry. The ionization execution time can be arbitrarily set as long as it is within this time zone. For example, the start times may be matched, set when the pinch valve 105 is closed, or the end times may be matched. The control circuit 38 generates a barrier discharge during the set ionization execution time. In the barrier discharge, when an AC voltage of several kV and several MHz is applied from the barrier discharge AC power source 4 to the two barrier discharge units 5 arranged outside the dielectric container 1, the barrier discharge is generated in the barrier discharge unit 5. To do. Moisture (H ₂ O) and oxygen molecules (O ₂ ) in the atmosphere passing through the barrier discharge unit 5 are changed into reaction ions such as H ₃ O ⁺ and O ₂ ⁻ by the barrier discharge, and are sent to the mass analysis unit 101. Moving.

  In step S10, as shown in FIG. 10A, the control circuit 38 closes the pinch valve 105 after a predetermined time (30 ms to 100 ms) has elapsed since the pinch valve 105 was opened in step S8.

  In step S11, the control circuit 38 accumulates ions such as the sample gas ionized in step S9 into the mass analysis unit 101. Step S11 starts in conjunction with the start of ionization in step S9. The end of step S11 and the end of ionization in step S9 are after the closing of the pinch valve 105 in step S10, as shown in FIGS. 10 (a) and 10 (b).

  In step S <b> 12, the control circuit 38 waits for 1 to 2 seconds from the end of step S <b> 10 (closing the pinch valve 105) until the pressure in the vacuum chamber 30 housed in the mass analysis unit 101 sufficiently decreases. When the pinch valve 105 is closed in step S10, the pressure in the dielectric container 1 (see FIG. 10B) and the pressure in the vacuum chamber 30 (see FIG. 10C) gradually decrease. Then, the pressure in the vacuum chamber 30 (see FIG. 10C) reaches a pressure capable of mass spectrometry (0.1 Pa or less) after 1 to 2 seconds from the closing of the pinch valve 105. Therefore, by waiting for 1 to 2 seconds, the mass analyzer 101 is in a state (pressure) in which mass analysis is possible. Specifically, the control circuit 38 monitors the degree of vacuum (pressure) in the vacuum chamber 30 with the vacuum gauge 35, and the pressure in the vacuum chamber 30 is a predetermined pressure (less than 0.1 Pa capable of mass analysis). It is determined whether or not (pressure) is reached. And when it determines with a pressure not reaching below a predetermined pressure, it does not progress to step S13 but implements this determination repeatedly. And when it determines with the pressure having reached the predetermined pressure or less, it progresses to step S13.

  In step S13, the control circuit 38 performs mass analysis (mass scan). Ion selection, ion dissociation, and mass separation are performed and the measurement results are stored.

  In step S14, the control circuit 38 determines whether or not to end the measurement of the same measurement sample 19 based on an input from the operator or the like. When the measurement of the same measurement sample 19 is not completed and another measurement is continued with the same measurement sample 19 (No in step S14), the process returns to step S8 and the measurement is performed again. Thereby, the measurement sample 19 can be repeatedly subjected to mass spectrometry. When the measurement of the same measurement sample 19 is to be ended (step S14, Yes), the process proceeds to step S15.

  In step S15, the operator moves the Y-axis rear stage 140 together with the cartridge 104A as shown in the change from FIG. 7A (third state) to FIG. 6A (second state) and further to FIG. 5A (first state). Move in a direction away from the slide valve 103. In the second state shown in FIG. 6A, the upper heater 120 is separated from the recessed portion 15 a 1 and further removed from the heater introduction hole 173 of the storage box 172. Further, the lower heater 110 is separated from the measurement container cup 16A.

  In step S16, in conjunction with the movement of the Y-axis rear stage 140 of the cartridge 104A indicated by the change from FIG. 6A to FIG. 5A by the operator, the slide valve valve body 7 moves into the slide valve container 6 and slides. The valve 103 is closed. As a result, the slide hole 6 b communicating with the inside of the dielectric container 1 is closed by the slide valve 103.

  In step S17, the operator moves the Y-axis rear stage 140 together with the cartridge 104A in the direction away from the slide valve 103 as shown in the change from FIG. 6A to FIG. 5A. The thin tube 17a is completely extracted from the slide valve container 6.

  In step S18, the operator removes the cartridge 104A from the storage box 172 (main body) in the first state.

  In step S19, the operator determines whether there is a measurement sample 19 to be measured next. If the next measurement sample 19 is present (step S19, Yes), the process returns to step S2, and if not (step S19, No), the flow of the mass spectrometry method is terminated.

  FIG. 11 shows (a) opening and closing of the pinch valve 105 in correspondence with the sequence of the mass spectrometry method (ion accumulation and exhaust waiting (time) -ion selection-ion dissociation-mass separation) in the mass spectrometer 100 of the present invention. (B) pressure of the barrier discharge part, (c) pressure of the mass analysis part, (d) AC voltage of the barrier discharge electrode, (e) orifice DC voltage, (f) DC voltage of the incap electrode and end cap electrode, ( g) shows a trap bias voltage, (h) a trap RF voltage, (i) an auxiliary AC voltage, and (j) on / off of the ion detector.

  As shown in FIG. 11, the mass analysis sequence is composed of five steps: an ion accumulation step, an exhaust waiting (time) step, an ion selection step, an ion dissociation step, and a mass separation step. It should be noted that the ion accumulation step and the exhaust waiting (time) step may proceed simultaneously and may overlap each other in time, or may be performed sequentially at different times.

(Ion accumulation step)
First, as shown in FIG. 11A, the pinch valve 105 is opened. Then, as shown in FIGS. 11B and 11C, the pressure in the barrier discharge unit 5 (in the dielectric container 1) and the pressure in the mass analysis unit 101 are increased. As shown in FIG. 11 (d), several kV, several kV from the barrier discharge AC power supply 4 is applied to the barrier discharge unit 5 at the timing when the pressure of the barrier discharge unit 5 (dielectric container 1) rises to an appropriate value. An AC voltage or pulse voltage of MHz is applied to generate a barrier discharge. The ions generated in the barrier discharge section 5 are suitable for the viscous flow of the sample gas, the orifice 3, the incap electrode, the linear ion trap electrodes 31a, 31b, 31c, 31d (see FIG. 1B), and the end cap electrode, respectively. By applying a DC voltage (for example, when the sample molecular ion to be measured is a positive ion, 0V to the orifice 3, -5V to the incap electrode, -10V to the linear trap electrode, and -5V to the end cap electrode). The gas 24 introduced into the analysis unit 101 is carried into the linear trap electrode. When a trap RF voltage (see FIG. 11 (h)) is applied to the linear ion trap electrodes 31a, 31b, 31c, and 31d after an appropriate delay time from the application of the barrier discharge electrode voltage, the sample molecular ions become linear ion traps. The electrodes 31a, 31b, 31c, and 31d are trapped (stored) linearly at the center.

(Exhaust waiting step)
Although the exhaust waiting step and the ion accumulation step are overlapped, the process waits until the pinch valve 105 is closed and the pressure in the vacuum chamber 30 becomes 0.1 Pa or less at which mass analysis is possible. Wait about 0.5 to 3 seconds until the pressure in the vacuum chamber 30 drops to 0.1 Pa or less. The pressure in the vacuum chamber 30 is monitored with a vacuum gauge 35.

(Ion selection step)
In the ion selection step, in order to select sample molecule ions (target ions) having an m / z value within a specific range among the trapped ions, as shown in FIG. 11 (i), the linear ion trap electrode 31a and An auxiliary AC voltage 39a (see FIG. 1 (b)) is added to 32b, and the trap RF voltage 39b (see FIG. 1 (b)) is also increased as shown in FIG. 11 (h), and FNF (Filtered Noise Field) processing is performed. As a result, sample molecular ions other than the m / z value in the range to be measured are discharged from the trap region. In addition, this FNF process is abbreviate | omitted when carrying out mass separation of all the trapped sample molecular ions.

(Ion dissociation step)
In the ion dissociation step, the sample molecule ions are processed by CID (Collision Induced Dissociation) to generate product ions. As shown in FIG. 11 (i), an auxiliary AC voltage 39a that matches the m / z value of a precursor ion (target ion) that is a CID target is applied to the linear ion trap electrodes 31a and 31b, and the precursor ion is subjected to mass spectrometry. Collide with neutral molecules (N ₂ or O ₂ ) in the portion 101 to cause fragmentation (dissociation) (generation of fragment ions). The precursor ions resonate with the auxiliary AC voltage 39a and are decomposed by multiple collisions with neutral molecules (buffer gas) in the trap to generate fragment ions. The buffer gas pressure is preferably about 0.01 to 1 Pa. In addition, this CID process is abbreviate | omitted when it is not necessary to carry out mass separation of the product ion.

(Mass separation step)
Finally, as shown in FIG. 11 (h) and FIG. 11 (i), the trap RF voltage 39a, 39b and the auxiliary AC voltage 39a are swept in voltage values (crest values), and ions having a small m / z value are detected. In order, the ions are discharged from the slit 31e of the linear ion trap electrode 31a toward the ion detector 34. A difference in detection timing at the ion detector 34 resulting from a difference in m / z value is recorded as an MS spectrum of mass spectrometry. That is, a mass spectrometry spectrum can be acquired from the detected ion mass number and its signal amount. In the mass scanning step, it is necessary to turn on the voltage of the ion detector 34 as shown in FIG. Since the voltage of the ion detector 34 is a high voltage that requires time for stabilization, it may be turned on during the ion selection step or the ion dissociation step. This is because it is assumed that a high voltage cannot be applied in a high pressure region such as an electron multiplier as the ion detector 34. When using a photomultiplier or a semiconductor detector for the ion detector 34, The voltage of the ion detector 34 can be always turned on during operation (always on), and the on / off switching operation can be omitted.

  The MS / MS measurement is performed in the above five steps of the ion accumulation step, the exhaust waiting step, the ion selection step, the ion dissociation step, and the mass separation step. Steps can be omitted. When performing MS / MS analysis (MSn) a plurality of times, the ion selection step and the ion dissociation step may be repeated a plurality of times.

  A specific example of a container (cartridge 104A) for measuring a liquid sample is shown. The measurement sample (liquid) 18 is put in the measurement container cup 16A and sealed with the measurement container cap part 15a. The measurement container cap portion 15a has a space S connected to the head space 21 of the measurement container cup 16A. The space S is connected to a head space decompression pipe 17 (see FIG. 1A) and a sample gas pipe 17b (see FIG. 1A). The connecting through holes 15f and 15d1 (see FIG. 2B) are connected. The elastic tube 17c is further connected to a thin tube 17a held by a body 15A having a measurement container cap portion 15a. The cartridge 104A configured by the measurement container cup 16A, the body 15A having the measurement container cap portion 15a, and the nozzle 17A may be contaminated by the sample gas from which the measurement sample (liquid) 18 is volatilized. By making it disposable and using a new cartridge 104A for each measurement, erroneous detection due to contamination can be prevented. In addition, the through hole 15f of the measurement container cap portion 15a is connected to the head space decompression pipe 17, and an open / close valve 45 and a leak pipe 46 (see FIG. 1A) are attached to the head space decompression pipe 17.

  When the on-off valve 45 is in the open state, the pressure of the head space 21 of the measurement container cup 16A is such that the flow of the gas 22 exhausted from the head space decompression pipe 17 and the flow of outside air (atmosphere 47) flowing in from the leak pipe 46. It depends on. That is, by adjusting the conductance of the leak pipe 46, the pressure of the head space 21 of the measurement container cup 16 can be adjusted.

  Further, the measurement container cup 16 </ b> A is heated by the lower heater 110. Thus, the measurement sample (liquid) 18 is vaporized into the head space 21 by reducing the pressure of the head space 21 and heating the measurement container cup 16 </ b> A with the lower heater 110. A part of the generated sample gas is exhausted to the head space decompression pipe 17 side as the flow of the sample gas 22.

  When the opening / closing valve 45 of the head space decompression pipe 17 is closed, the pressure of the head space 21 of the measurement container cup 16A is maintained at atmospheric pressure by the flow of outside air (atmosphere) 47 flowing from the leak pipe 46. In this case, the measurement sample (liquid) 18 is vaporized in the head space 21 only by heating with the lower heater 110. Therefore, the temperature of the lower heater 110 needs to be higher than when the on-off valve 45 is in the open state. Further, since the pressure in the head space 21 is atmospheric pressure, the state in which the pinch valve 105 is opened when the pinch valve tip 12 moves downward is shortened, or the conductance of the sample gas pipe 17b and the narrow pipe 17a is reduced. Thus, it is preferable that the amount of flow of the sample gas 22 to be measured is the same as that when the on-off valve 45 is opened.

  In the container (cartridge 104A) for measuring the liquid sample, if the measurement sample (liquid) 18 is heated too much, the measurement sample (liquid) 18 boils in the measurement container cup 16A, and the headspace decompression pipe 17 Since the measurement sample (liquid) 18 may flow into the sample gas pipe 17b, the temperature of the lower heater 110 can only be raised to a temperature at which the measurement sample (liquid) 18 does not boil.

  By the way, if the head space 21 is depressurized when the opening / closing valve 45 is in the open state, the boiling point of the measurement sample (liquid) 18 is lowered, so that the heating temperature may not be sufficiently increased. In such a case, it is necessary to heat and measure the measurement sample in a solid state. Below, the case where a measurement sample is a solid is demonstrated.

  The specific example of the container (cartridge 104B) in the case of measuring solid samples, such as powder and a plant piece, is shown. A heating probe 16f is fitted into the measurement container cup 16B, and a measurement sample (solid) 19 is attached to the tip of the heating probe 16f. The measurement container cap portion 15i is provided with a space (hollow portion) S into which the tip of the heating probe 16f enters when the measurement container cup 16B is attached.

  Further, when the heating probe 16 f is heated by the lower heater 110, sample gas sublimated (gasified) is generated from the measurement sample (solid) 19. In this state, if the pinch valve tip 12 is intermittently moved up and down using the pinch valve drive unit 13, the pinch valve 105 is opened when the pinch valve tip 12 moves down, and one of the sublimated sample gas The portion becomes a gas 23 introduced into the ion source 102 and is supplied to the ion source 102 side. The sublimated sample gas rides on the flow of outside air (atmosphere) rising from the gaps T1 and T2 formed between the cup portion 16g of the measurement container cup 16B and the heating probe 16f by the heat of the lower heater 110. It is discharged out of the cartridge 104B through the space S, the communication space S11, and the space S10 of the measurement container cap portion 15i.

1 Dielectric container (dielectric barrier)
2 High voltage application electrode 3 Orifice 4 Barrier discharge AC power supply 5 Plasma or thermoelectron 6 Slide valve vessel 6a Through hole 6b Slide hole 7 Slide valve valve body 8a Valve body shaft 8b Vacuum bellows 8c Guide roller 8d Compression coil spring 9a 1O Ring 9b Second O-ring 9c Valve body O-ring 12 Pinch valve tip 13 Pinch valve drive unit 15A, 15B Body 15a, 15i Measurement container cap (measurement container)
15a1 recess 16A, 16B Measuring container cup (measuring container)
16f Heating probe 16f1 Support plate 16f2 Pin 16f3 Recessed part 16g Cup part 16g1 Reduced diameter part 16g2 Opening part 17 Headspace decompression piping 17A, 17B Nozzle (introduction pipe)
17a Narrow tube 17b Sample gas piping 17c Elastic tube 18 Measurement sample (liquid)
18a, 18b Fixed wedge 19 Sample (solid)
21 Headspace 22 Gas to be Exhausted 23 Gas to be Introduced into Ion Source 24 Gas to be Introduced into Mass Analyzer 25 Mass-Separated Sample Molecular Ion 26 Gas Exhausted from Vacuum Chamber 30 Vacuum Chamber 34 Ion Detector 35 Vacuum Gauge 36 Turbo molecular pump 37 Roughing pump 38 Control circuit 45 Open / close valve 46 Leak piping 47 Incoming outside air (atmosphere)
DESCRIPTION OF SYMBOLS 100 Mass spectrometer 101 Mass spectrometry part 102 Ion source 103 Slide valve 104A Cartridge (for liquid samples, sample introduction part)
104B cartridge (for solid sample, sample introduction part)
105 Pinch valve 110 Lower heater (first heater, heater, heating unit)
120 Upper heater (second heater, heating part)
120d End face 120s Claw (projection)
121 Resin block (resin member)
122 Arm (metal member)
123 Compression coil spring (biasing member)
140 Y-axis rear stage 180 Slider 180a Crank-shaped guide hole S10 space S11 communication space (space)
T1, T2 clearance

Claims (10)

A sample introduction section that introduces a measurement sample and is detachable from the main body;
A heating unit that gasifies the measurement sample by heating to generate a sample gas;
An ion source for ionizing the sample gas;
A mass spectrometer for separating the ionized sample gas,
The ion source is internally depressurized by differential exhaust from the mass spectrometer,
The sample introduction unit includes a measurement container for containing the measurement sample, and an introduction pipe for intermittently introducing the sample gas generated in the measurement container into the ion source,
The heating unit includes a first heater that gasifies the measurement sample, and a second heater that heats a space in which the gasified sample gas stays ,
The second heater is supported by a resin member,
The mass spectrometer is characterized in that the resin member is supported by a metal member . The mass spectrometer according to claim 1 , wherein the resin member includes an urging member that is in close contact with the measurement container. The introduction tube includes a thin tube connected to the ion source, and an elastic tube connecting the measurement container and the thin tube,
The mass spectrometer according to claim 1, wherein the main body includes a valve that closes the flow path by sandwiching the elastic tube and opens the flow path by being separated from the elastic tube. The mass spectrometer according to claim 3 , wherein the second heater includes a protrusion that heats the periphery of the elastic tube on the upstream side of the valve. Before SL sample introduction section, the mass spectrometer according to claim 1 which is connected to the front Symbol inlet tube, characterized in that it comprises between air that generates the ascending air current in the sample gas.   The mass spectrometer according to claim 1, wherein the sample introduction unit is a disposable type. A cartridge detachably attached to a main body used in a mass spectrometer for gasifying a measurement sample with a heater to generate a sample gas and separating the sample gas ionized with an ion source,
The cartridge includes a body having a measurement container for containing the measurement sample, and an introduction tube that is supported by the body and intermittently introduces the sample gas generated in the measurement container into the ion source,
The body includes a space that communicates with the introduction pipe and generates an updraft in the sample gas ;
The measurement container includes a heating probe that contacts the heater, and a cup portion that detachably holds the heating probe.
The cartridge in which the cup part is formed with an opening for removing the heating probe by the operation of the heater . The cartridge according to claim 7 , wherein a gap is formed between the heating probe and the cup portion when the heating probe is detached. The heating probe includes a support plate supported by the cup portion, and a pin extending from the support plate toward the space,
The cartridge according to claim 7 , wherein a recess for accommodating the measurement sample is formed at a tip of the pin. The cartridge according to any one of claims 7 to 9 , wherein the cartridge is a disposable type.

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