JP6167969B2 - Sampling unit and ICP mass spectrometer having the same - Google Patents

Description

  The present invention relates to a sampling unit and an ICP mass spectrometer equipped with the sampling unit, and more particularly to an ICP mass spectrometer using a high frequency inductively coupled plasma (ICP) as an ion source.

The ICP mass spectrometer is currently attracting attention as an apparatus capable of performing highly sensitive elemental analysis. FIG. 10 is a schematic configuration diagram illustrating an example of a conventional ICP mass spectrometer. 11 is a perspective view showing an appearance of the ICP mass spectrometer shown in FIG. 10, and FIG. 12 is an enlarged perspective view of A shown in FIG. One direction horizontal to the ground is defined as an X direction (axis direction), a direction horizontal to the ground and perpendicular to the X direction is defined as a Y direction, and a direction perpendicular to the X direction and the Y direction is defined as a Z direction.
The ICP mass spectrometer 101 includes a plasma torch (plasma ion source) 10, a sampling unit 120 disposed in front of the plasma torch 10 (X direction), and a mass analyzing unit 130 disposed adjacent to the sampling unit 120. A low vacuum pump 38 such as a rotary pump, high vacuum pumps 36 and 37 such as a turbo molecular pump, a power source 42 and a cooling solvent supply source 41 connected to the sampling unit 120, and a gas supply connected to the plasma torch 10. A source 43 and a controller (not shown) that controls the entire ICP mass spectrometer 101 are provided (see, for example, Patent Document 1).

  The plasma torch 10 includes a cylindrical glass sample gas tube (not shown), a cylindrical glass plasma gas tube (not shown) that covers the outer peripheral surface of the sample gas tube with a space therebetween. A cylindrical glass coolant gas tube 11 covering the outer peripheral surface of the plasma gas tube with a space, and a high frequency induction coil 12 wound around the tip of the outer peripheral surface of the coolant gas tube 11 for two to four turns. And a gas inlet 13. And the gas inlet 13 is connected with the gas supply source 43, and argon gas is supplied.

The sampling unit 120 includes a housing 121 made of aluminum or copper blocks (for example, 13 cm × 9 cm × 2.5 cm) having through holes in the X direction, and the sampling cones are sequentially arranged from the plasma torch 10 side (toward the X direction). 151, a skimmer cone 152, and an extractor electrode 153 are arranged.
A cooling solvent flow path (not shown) for circulating cooling water is formed in the wall of the casing 121, and the cooling solvent supply source 41 and the inlet / outlet of the cooling solvent flow path are connected to each other. Thereby, the housing | casing 121 is cooled with a cooling water. An opening is formed in the wall of the housing 121 and is connected to the low vacuum pump 38. Thereby, the inside of the housing 121 is in a vacuum state (for example, 150 to 200 Pa) by the low vacuum pump 38.

  The sampling cone 151 is a metal body having a disc body (for example, 6 cm in diameter) and a conical portion formed at the center of the disc body, and a circular opening 151a is formed at the center of the conical portion. ing. The opening 151a of the sampling cone 151 has a shape that gradually widens in the ion traveling direction (X direction). The sampling cone 151 can be attached and detached using the side wall of the casing 121 on the plasma torch 10 side and the two screws 151b.

  The skimmer cone 152 is a metal body having a disc body (for example, 3 cm in diameter) and a conical portion formed in the center of the disc body, and a circular opening 152a is formed in the center of the conical portion. ing. The opening 152a of the skimmer cone 152 has a shape that gradually widens in the ion traveling direction (X direction). The skimmer cone 152 can be attached and detached using the inside of the housing 121 and a screw (not shown).

  The extractor electrode 153 is a metal body having a disc body (for example, a diameter of 5 cm) and a cylindrical portion 153a formed at the center of the disc body. The extractor electrode 153 is connected to the power source 42 and is applied with a voltage of 0 to 700V. The extractor electrode 153 can be attached and detached using a side wall opposite to the plasma torch 10 side of the casing 121 and two screws (not shown).

  The mass spectrometric unit 130 includes a first chamber 131 having an aluminum case-like (eg, 14 cm × 12 cm × 10 cm) casing 131a and a second case 32 having an aluminum case-like (eg, 10 cm × 33 cm × 10 cm) casing 32a. And a chamber 32. An ion lens section 33 such as a converging lens is disposed in the casing 131a, a mass separation section 34 such as a quadrupole rod structure is disposed in the casing 32a, and an electromultiplier or the like is provided in the last stage. A detector 35 is arranged.

  In such an ICP mass spectrometer 101, a plasma P is generated by passing a high-frequency current through the high-frequency induction coil 12 of the plasma torch 10, and the sample is ionized by the heat of the plasma P at 5000 ° C. to 6000 ° C. Plasma P is introduced into the housing 121 through the opening 151 a of the skimmer cone 151. The ions introduced into the casing 121 are sequentially introduced through the opening 152a of the sampling cone 152 and the cylindrical portion 153a of the extractor electrode 153 into the casing 131a. In the casing 131a, the ions from the sampling unit 120 are converged toward the rear second chamber 32 by the ion lens unit 33.

  In the mass separation unit 34 to which a voltage obtained by superimposing a DC voltage and a high frequency voltage is applied, only ions having a mass number (mass m / charge z) corresponding to the applied voltage are selectively passed. The ions reach the detector 35. At this time, since the mass number of ions passing through the second chamber 32 depends on the applied voltage, an ion intensity signal for ions having a predetermined mass number is obtained by the detector 35 by manipulating the voltage. be able to.

  By the way, in the ICP mass spectrometer 101, the sampling cone 151 is directly exposed to the plasma P, and since ions pass through the opening 151a, the sampling cone 151 is a component that is easily deteriorated by heat or easily contaminated with dirt. When dirt is attached, the aperture 151a becomes smaller, or the aperture 151a becomes larger due to deterioration due to heat, and the state of the electric field is changed to lower the analysis sensitivity. Therefore, the sampling cone 151 is relatively frequently maintained. There is a need. Similarly, the skimmer cone 152 and the extractor electrode 153 need to be maintained relatively frequently. Therefore, the ICP mass spectrometer 101 has a structure that can be detached from the casing 121 in order to maintain the sampling cone 151, the skimmer cone 152, and the extractor electrode 153.

  FIG. 13 is a diagram when the ICP mass spectrometer 101 shown in FIG. 10 is maintained. As shown in FIG. 13, at the time of maintenance, the screws 151b and the like were first removed, and the sampling cone 151, skimmer cone 152, and extractor electrode 153 were pulled out from the casing 121 in the direction opposite to the axial direction (−X direction). At this time, since the plasma torch 10 exists in the pulling direction (−X direction), the plasma torch 10 is formed so as to be removable from a predetermined position before starting maintenance or to move in the −X direction from the predetermined position. ing.

Japanese Patent Laid-Open No. 11-144672

However, in the ICP mass spectrometer 101 in which the plasma torch 10 is formed so as to be removable, it takes time to remove the plasma torch 10, and the position of the plasma torch 10 needs to be adjusted when the plasma torch 10 is once removed. It took a lot of time and effort.
Further, the ICP mass spectrometer 101 in which the plasma torch 10 is configured to be movable in the −X direction requires a space for moving the plasma torch 10, so that the size of the ICP mass spectrometer 101 is increased. It was.

  In order to solve the above problems, the present inventors have studied a sampling unit that can easily maintain the sampling cone, the skimmer cone, and the extractor electrode without increasing the size of the apparatus. Therefore, the present inventors have found that the sampling unit has a structure in which the sampling cone, the skimmer cone, and the extractor electrode are attached, and is removed from the mass analysis unit and attached to the mass analysis unit.

By the way, when the sampling unit as described above is removed from the mass analysis unit, it is necessary to remove the cooling solvent supply source 41 from the inlet / outlet of the cooling solvent flow path and to remove the power source 42 from the extractor electrode 153. Further, when the sampling unit as described above is attached to the mass analysis unit, it is necessary to attach the cooling solvent supply source 41 to the inlet / outlet of the cooling solvent flow path and to attach the power source 42 to the extractor electrode 153. For this reason, these operations were very time-consuming.
Therefore, the inventors of the present invention have a structure in which an O-ring (annular elastic body) is disposed at the inlet / outlet of the cooling solvent flow path and pressed against the mass analyzing unit, so that the cooling solvent flow path inlet / outlet and the cooling solvent supply are provided. It has been found that the source can be easily coupled.
Simply connecting them causes the cooling water remaining in the sampling section to leak out when the sampling section is removed, so an Ar purge function is added to the device to purge the cooling water remaining in the sampling section cooling water flow path. By doing so, the sampling part can be attached and detached without polluting the surroundings.

  That is, the sampling unit of the present invention is disposed between a plasma ion source that ionizes a sample with plasma and a mass analysis unit that performs mass analysis on the ionized sample, and the sampling cone and the skimmer cone are arranged in this order in the axial direction. The sampling unit is attached and can be removed, with the sampling cone, the skimmer cone, and the extractor being attached, removed from the mass analysis unit, and attached to the mass analysis unit. The cooling solvent flow path is connected to an inlet / outlet of a cooling solvent supply channel formed in the mass spectrometer, and an annular elastic member is provided at the inlet / outlet of the cooling solvent channel. A body is arranged so as to be pressed against the mass spectrometer.

  As described above, according to the sampling unit of the present invention, it is possible to realize the sealing of the cooling solvent by crushing the annular elastic body, and as a result, the inlet / outlet of the cooling solvent flow path and the cooling solvent supply source are provided. Can be easily connected.

(Means and effects for solving other problems)
Further, the sampling unit of the present invention has a sampling unit side power contact point connected to the mass analysis unit side power contact point formed in the mass analyzing unit, and the sampling unit side power contact point protrudes. You may make it form in this.
According to the sampling unit of the present invention, the sampling unit side power contact point and the mass analysis unit side power contact point can be easily connected.

  In the sampling unit of the present invention, the other end is rotated from the mass analyzing unit by a predetermined distance in the direction opposite to the axial direction by rotating the other end with the one end serving as a rotation axis, and then perpendicular to the axial direction. Is moved from the mass analysis unit and moved in a direction perpendicular to the axial direction, and then held by the mass analysis unit with one end as a rotation axis. The other end may be rotated, and the other end may be moved in the axial direction by a predetermined distance toward the mass analyzer, so that the structure can be attached to the mass analyzer.

  Here, the “predetermined distance” is an arbitrary distance determined in advance by a designer or the like. For example, a distance that does not contact the plasma coil or a distance that moves the plasma coil in the direction opposite to the axial direction is shortened. For example, about 1 cm.

  Further, in the sampling unit of the present invention, the first plate-like body to which the sampling cone is attached, and the second plate-like body to which the skimmer cone and the extractor electrode are attached, A cooling-fluid channel groove serving as the cooling-solvent channel is formed, and the second plate-like body is formed with the sampling-unit-side power contact point and the inlet / outlet of the cooling-solvent channel. It may be.

  Furthermore, in the ICP mass spectrometer of the present invention, the sampling unit as described above, a plasma ion source that ionizes the sample by plasma, a mass analyzer that mass analyzes the ionized sample, and cooling that supplies a cooling solvent. A solvent supply source; a gas supply source that supplies gas; and a control unit that controls the gas supply source. The mass analysis unit includes a cooling solvent supply channel, and the control unit includes: When mass-analyzing the sample, a gas is supplied to the plasma ion source and a cooling solvent is supplied to the cooling solvent supply flow path, while maintenance of the sampling cone, skimmer cone, and extractor electrode is performed. Alternatively, a gas may be supplied to the cooling solvent supply flow path for a predetermined time, and the cooling solvent flow path may be purged.

  According to the ICP mass spectrometer of the present invention, the cooling solvent filled in the cooling solvent flow channel is prevented from leaking when the sampling unit is attached / detached after cooling by flowing the cooling solvent. be able to.

The schematic block diagram which shows an example of the ICP mass spectrometer which concerns on this invention. FIG. 2 is an enlarged sectional view of a part of the ICP mass spectrometer shown in FIG. 1. The perspective view which shows the back surface of the removed sampling part. FIG. 4 is a cross-sectional perspective view of the sampling unit shown in FIG. 3. FIG. 4 is a cross-sectional perspective view of the sampling unit shown in FIG. 3. The perspective view which shows the back surface of a 1st plate-shaped object. The perspective view which shows an example of the mass spectrometry part at the time of sampling part attachment. The perspective view which shows an example of the mass spectrometry part at the time of sampling part removal. The perspective view which shows an example of the mass spectrometry part at the time of the attachment operation | work of a sampling part. The schematic block diagram which shows an example of the conventional ICP mass spectrometer. The perspective view which shows the external appearance of the ICP mass spectrometer shown in FIG. The expansion perspective view of A shown in FIG. The figure which shows the state at the time of the maintenance of the ICP mass spectrometer of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments described below, and it goes without saying that various aspects are included without departing from the spirit of the present invention.

FIG. 1 is a schematic configuration diagram showing an example of an ICP mass spectrometer according to the present invention, and FIG. 2 is an enlarged cross-sectional view of a part of the ICP mass spectrometer shown in FIG. In addition, the same code | symbol is attached | subjected about the thing similar to the ICP mass spectrometer 101 mentioned above.
The ICP mass spectrometer 1 includes a plasma torch (plasma ion source) 10, a sampling unit 20 disposed in front of the plasma torch 10 (X direction), and a mass analyzing unit 30 disposed adjacent to the sampling unit 20. A low vacuum pump 38 such as a rotary pump, high vacuum pumps 36 and 37 such as a turbo molecular pump, a power source 42 and a cooling solvent supply source 41 connected to the mass analysis unit 30, a plasma torch 10 and a mass analysis unit 30. A gas supply source 43, a switching mechanism 44, and a control unit (not shown) for controlling the entire ICP mass spectrometer 1.

Here, FIG. 3 is a perspective view showing the back surface of the sampling unit 20 in a removed state. 4 and 5 are cross-sectional perspective views of the sampling unit 20 shown in FIG.
The sampling unit 20 includes a first plate 21 made of aluminum or copper, and a second plate 22 made of aluminum or copper, and a sampling cone 51 and a skimmer cone 52 in order (X direction) from the plasma torch 10 side. An extractor electrode 53 is disposed.

The sampling cone 51 is a metal body having a disc body (for example, a diameter of 6 cm) and a conical portion formed at the center of the disc body, and a circular opening 51a is formed at the center of the conical portion. ing. The opening 51a of the skimmer cone 51 has a shape that gradually widens in the ion traveling direction (X direction).
The skimmer cone 52 is a metal body having a disc body (for example, 3 cm in diameter) and a conical portion formed at the center of the disc body, and a circular opening 52a is formed at the center of the conical portion. ing. The opening 52a of the sampling cone 52 has a shape that gradually expands in the ion traveling direction (X direction).
The extractor electrode 53 is a metal body having a disc body (for example, a diameter of 5 cm) and a cylindrical portion 53a formed at the center of the disc body.

  FIG. 6 is a perspective view showing the back surface of the first plate-like body 21. The first plate-like body 21 has a rectangular flat plate shape (for example, 13 cm × 9 cm × 1.5 cm). And the opening part 21a penetrated to an axial direction (X direction) is formed in the center part of the 1st plate-shaped object 21. As shown in FIG. As shown in FIG. 2, the sampling cone 51 can be attached to and detached from the central portion of the surface of the first plate 21 using two screws 51b. Further, on the back surface of the first plate-like body 21, a cooling solvent channel groove 21c serving as a cooling solvent channel, a vacuum packing groove 21d around the opening 21a, and a cooling solvent channel are provided. A cooling solvent packing groove 21e is formed at a position around the groove 21c (see FIG. 4). Furthermore, annular packings (elastic bodies) 21c 'are respectively arranged at the positions serving as the inlet and the outlet of the cooling solvent flow path.

  As shown in FIG. 3, the second plate-like body 22 has a rectangular flat plate shape (for example, 13 cm × 9 cm × 1 cm), and the second plate-like body 22 has a central portion in the axial direction (X direction). A penetrating circular (for example, 2 cm in diameter) high vacuum opening 22a is formed. In addition, an inclined portion 22k whose rear surface is inclined at a predetermined angle (for example, 15 °) in the −X direction is formed at the left end portion of the second plate-like body 22 in the drawing. Circular holding grooves 22e (for example, 1 cm in diameter) are formed side by side in the vertical direction (Z direction), and an elliptical low-vacuum opening penetrating in the X direction is formed on the right side of the holding grooves 22e. A portion 22b is formed. Furthermore, in the lower right part of the figure of the second plate-like body 22, two circular (for example, 5 cm in diameter) cooling solvent inlet / outlet ports 22 c penetrating in the X direction are formed. Are each provided with an annular packing (elastic body) 22c '.

  The skimmer cone 52 can be attached to and detached from the central portion of the surface of the second plate 22 and the extractor electrode 53 is provided with two screws at the center of the back surface of the second plate 22. It is possible to attach and remove using 53b. Further, inside the upper right portion of the second plate-like body 22 shown in FIG. 5, a metal power supply connecting rod 22h is arranged so as to extend in the horizontal direction (Y direction), and one end portion of the power supply connecting rod 22h. Is formed with a metal power supply terminal (sampling part side power contact point part) 22j protruding toward the back surface side, and the center part of the back surface of the second plate-like body 22 serving as the other end of the power supply connecting rod 22h. Are formed with a metal power supply terminal 22 i that is electrically connected to the attached extractor electrode 53.

  The first plate-like body 21 and the second plate-like body 22 are formed after the packing (elastic bodies) 21d ′ and 21e ′ are arranged in the vacuum packing groove 21d and the cooling solvent packing groove 21e. The front surface of the second plate-like body 22 and the back surface of the first plate-like body 21 are attached by using four screws 21f. At this time, the periphery of the opening 21a of the first plate 21 and the high vacuum opening 22a and the low vacuum opening 22b of the second plate 22 are connected while being sealed (sealed) with the packing 21d ′. The Further, the periphery of the coolant channel 21c of the first plate 21 and the surface of the second plate 22 are connected to each other while being sealed by the packing 21e '. At this time, a flow path is formed between the surface of the second plate-like body 22 and the cooling solvent flow path groove 21c of the first plate-like body 21, and the inlet / outlet of the cooling solvent flow path is the cooling solvent inlet / outlet 22c. And are connected while being sealed by the packing 21c ′.

Here, an example of a maintenance method for maintaining the sampling cone 51, the skimmer cone 52, and the extractor electrode 53 will be described.
First, the two screws 51b are removed from the first plate-like body 21, and the sampling cone 51 is removed. Next, the skimmer cone 52 is removed from the second plate-like body 22. Further, the two screws 53b are removed from the second plate-like body 22, and the extractor electrode 53 is removed.
Then, the sampling cone 51, skimmer cone 52, and extractor electrode 53 are maintained.
Next, the maintained extractor electrode 53 is attached to the center of the back surface of the second plate 22 by two screws 53b, and the maintained skimmer cone is mounted on the center of the surface of the second plate 22. 52 is installed. At this time, the extractor electrode 53 and the power supply terminal 22i are electrically connected. Next, the maintained sampling cone 51 is attached to the center of the surface of the first plate-like body 21 with two screws 51b.

Here, the mass spectrometer 30 to which the sampling unit 20 is attached or detached will be described. FIG. 7 is a perspective view showing an example of the mass analysis unit 30 when the sampling unit 20 is attached, and FIG. 8 is a perspective view showing an example of the mass analysis unit 30 when the sampling unit 20 is removed. FIG. 9 is a perspective view showing an example of the mass analysis unit 30 when the sampling unit 20 is attached.
A circular opening (for example, a diameter of 5 cm) that penetrates in the axial direction (X direction) is formed in the center of the front wall 31 of the mass analysis unit 30, and the right part of the front wall 31 extends in the X direction. A penetrating elliptical vacuum opening 31b is formed, and two circular (for example, 5 cm in diameter) cooling solvent supply passages 31c penetrating in the X direction are formed in the lower left portion of the front wall 31. The cooling solvent supply channel 31c is connected to a cooling solvent supply source 41 (see FIG. 1). In addition, a power supply terminal (mass analysis unit side contact part) 31d is formed on the upper left portion of the front wall 31, and the power supply terminal 31d is connected to a power source 42 (see FIG. 1).

  The power supply terminal (mass analysis part side contact part) 31d has a substantially cylindrical pin, an elastic body into which the pin is inserted, and a power supply plate arranged in the X direction of the pin. According to such a power supply terminal 31d, when the elastic body acts to move the pin in the -X direction, the pin and the power supply plate are brought into a non-contact state, while the pin opposes the elastic force of the elastic body. When moving in the direction, the pin and the power supply plate are in contact with each other.

  In addition, a guide portion 31e is formed in the upper and lower portions of the front wall 31 so as to extend in the horizontal direction (Y direction), and two protrusions 31f are formed in the vertical direction (Z A screw hole 31g into which a screw 22g is inserted is formed on the left side of the front wall 31. The guide portion 31e is formed so as to protrude from the front wall 31 in a −X direction by a predetermined distance (for example, 1 cm), and when the sampling portion 20 is attached / detached, the sampling portion 20 is fixed by the guide portion 31e in the −X direction. It does not move as described above, and moves in the Y direction while being separated from the front wall 31 by a predetermined distance. The two protrusions 31f have a cylindrical body shape (for example, a diameter of 1 cm and a height of 1 cm) protruding in the −X direction. When the sampling unit 20 is at a predetermined position of the mass analysis unit 30, the sampling unit 20 Inserted in the holding groove 22e, the sampling unit 20 rotates with the Z direction connecting the two projections 31f and 31f as the rotation axis.

  The switching mechanism 44 includes a first switching mechanism 44a and a second switching mechanism 44b. The first switching mechanism 44 a is configured to be in a state of supplying argon gas from the gas supply source 43 to the plasma torch 10 or supplying it to the mass analysis unit 30. The second switching mechanism 44b is configured to either supply the cooling water from the cooling solvent supply source 41 to the mass analyzer 30 or not supply it. The first switching mechanism 44a and the second switching mechanism 44b are controlled by the control unit.

  The control unit includes a CPU, and a display device having a monitor screen and an input device having a keyboard and a mouse are connected to each other. When the functions processed by the CPU are described in a block form, a switching mechanism control unit that controls the switching mechanism 44 is provided. When the “sample analysis” is input from the input device, the switching mechanism control unit controls the second switching mechanism 44b so as to supply the cooling water from the cooling solvent supply source 41 to the cooling solvent supply channel 31c. The first switching mechanism 44 a is controlled so that argon gas from the gas supply source 43 is supplied to the plasma torch 10. Then, when “input the sampling unit 20 from the mass analyzing unit 30” is input by the input device, the second supply is performed so as to stop the supply of the cooling water from the cooling solvent supply source 41 to the cooling solvent supply channel 31c. While controlling the switching mechanism 44b, the first switching mechanism 44a is controlled so that the argon gas from the gas supply source 43 is supplied to the cooling solvent supply channel 31c for a predetermined time (for example, 1 minute).

An example of a method for removing the sampling unit 20 from the mass analysis unit 30 will be described. First, the measurer inputs “remove sampling unit 20 from mass analysis unit 30” to the control unit. Thereby, the control unit supplies the argon gas to the cooling solvent supply channel 31c for a predetermined time. As a result, the cooling solvent filled in the cooling solvent flow path disappears, and the cooling solvent flow path is filled with argon gas.
Next, the screw 22g is removed from the screw hole 31g. Next, the left end portion of the sampling unit 20 is moved in the −X direction by a predetermined distance by rotating the sampling unit 20 around the two protrusions 31f as the rotation axis. Thereafter, the sampling unit 20 cannot move in the −X direction by the upper guide portion 31e and the lower guide portion 31e. Next, the sampling unit 20 is moved in the Y direction by the upper guide unit 31e and the lower guide unit 31e, so that the upper guide unit 31e, the lower guide unit 31e, and the front wall 31 of the mass analysis unit 30 are connected. The sampling part 20 is removed from between.

  Furthermore, an example of a method for attaching the sampling unit 20 to the mass analysis unit 30 will be described. First, the sampling unit 20 is inserted from the -Y direction between the upper guide unit 31e and the lower guide unit 31e and the front wall 31 of the mass analysis unit 30, and the lower end of the sampling unit 20 is connected to the lower guide unit 31e. Move it in the -Y direction while riding on. Thereafter, when the sampling unit 20 moves to a predetermined position of the mass analysis unit 30, the two holding grooves 22 e at the right end of the sampling unit 20 are inserted into the two protrusions 31 f of the mass analysis unit 30. Next, the left end portion of the sampling unit 20 is moved by a predetermined distance in the X direction by rotating the sampling unit 20 around the two protrusions 31f as the rotation axis. Next, the screw 22g is inserted into the screw hole 31g, and the sampling unit 20 is firmly fixed to the mass analysis unit 30. At this time, the high vacuum opening 22a is connected to the opening 31a and the low vacuum opening 22b is connected to the vacuum opening 31b while being sealed with the packing 31h, and the cooling solvent inlet / outlet 22c is connected to the cooling solvent supply channel 31c. The power supply terminal (sampling unit side power contact point) 22j is electrically connected by pressing the pin of the power supply terminal (mass analyzing unit side contact point) 31d in the X direction while being sealed with the packing 22c ′. .

  As described above, according to the ICP mass spectrometer 1 of the present invention, the sealing of the cooling solvent can be realized by crushing the packing 22c ′. As a result, the cooling solvent inlet / outlet port 22c and the cooling solvent supply flow path 31c can be realized. Can be easily connected. Further, the power supply terminal (sampling unit side power contact point) 22j and the power supply terminal (mass analysis unit side contact unit) 31d can be easily connected. Furthermore, when the sampling unit 20 is attached / removed after the cooling solvent is supplied and cooled, it is possible to prevent the cooling solvent filled in the cooling solvent flow channel from leaking.

  The present invention can be used for an ICP mass spectrometer or the like.

1: ICP mass spectrometer 10: Plasma torch (plasma ion source)
20: Sampling part 22c ': Packing (elastic body)
30: Mass spectrometer 31c: Cooling solvent supply channel 51: Skimmer cone 52: Sampling cone 53: Extractor

Claims (5)

It is arranged between a plasma ion source that ionizes a sample with plasma and a mass analyzer that performs mass analysis on the ionized sample,
Sampling cone, skimmer cone and extractor electrode are attached in this order in the axial direction, and can be removed,
With the sampling cone, skimmer cone, and extractor electrode attached, it is removed from the mass analyzer and is attached to the mass analyzer.
A cooling solvent flow path connected to an inlet / outlet of a cooling solvent supply flow path formed in the mass spectrometer;
A sampling unit, wherein an annular elastic body is disposed at an entrance of the cooling solvent flow path and is pressed against the mass analyzing unit. Having a sampling unit side power contact point connected to the mass analysis unit side power contact point formed in the mass analysis unit;
The sampling unit according to claim 1, wherein the sampling unit side power contact point is formed to protrude. By moving the other end from the mass analyzer by a predetermined distance in the direction opposite to the axial direction by rotating the other end with the one end serving as a rotation axis, and moving in the direction perpendicular to the axial direction, Removed from the mass spectrometer, and
After moving in a direction perpendicular to the axial direction, the mass analyzer is held at one end, the other end is rotated with one end as a rotation axis, and the other end is axially directed toward the mass analyzer. The sampling unit according to claim 1 or 2, wherein the sampling unit is configured to be attached to the mass analyzing unit by being moved a predetermined distance. A first plate body to which the skimmer cone is attached;
A second plate-like body to which the sampling cone and the extractor electrode are attached;
The first plate-like body is formed with a cooling solvent channel groove that becomes the cooling solvent channel,
The sampling part according to claim 2, wherein the second plate-like body is formed with the sampling part side power contact point part and an inlet / outlet of the cooling solvent flow path. The sampling unit according to any one of claims 1 to 4, and
A plasma ion source for ionizing a sample with plasma;
A mass spectrometer for mass-analyzing the ionized sample;
A cooling solvent supply source for supplying the cooling solvent;
A gas supply source for supplying the gas;
A control unit for controlling the gas supply source,
In the mass spectrometer, a cooling solvent supply channel is formed,
When the mass analysis of the sample is performed, the control unit supplies a gas to the plasma ion source and a cooling solvent to the cooling solvent supply channel, while the skimmer cone, the sampling cone, and the extractor electrode In the ICP mass spectrometer, the gas is supplied to the cooling solvent supply flow path for a predetermined time and the cooling solvent flow path is purged.

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