Technical Field
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The present invention relates to a mass spectrometer.
Background Art
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In general, a mass spectrometer includes components such as an ion source, an ion lens, a quadrupole mass filter, and an ion detector in a vacuum chamber. Here, a technique of using a turbomolecular pump to maintain an inside of the vacuum chamber in a high vacuum state is disclosed (see PTL 1).
Citation List
Patent Literature
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Summary of Invention
Technical Problem
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In a mass spectrometer in PTL 1 or the like, the vacuum chamber is supported by a frame structure. Here, the frame structure refers to a structure including a plurality of frame members such as columns and beams.
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The turbomolecular pump is attached to, for example, a sidewall or a lower portion of the vacuum chamber. Since the vacuum chamber and the turbomolecular pump have a large weight, the frame structure is manufactured by joining a large number of frame members.
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Periodic maintenance of the turbomolecular pump and repair at the time of a failure require a somewhat large work space. Here, when a plurality of mass spectrometers and the like are provided in a narrow space or when the mass spectrometers are disposed near a wall, an area that can be used as a work space is limited, and thus it is a problem to secure maintenance workability.
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The invention provides a mass spectrometer capable of securing a work space for maintenance or the like of a turbomolecular pump as compared with one in the related art.
Solution to Problem
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The invention includes a plurality of means for solving the above problems, and an example thereof includes one including an ion source, a vacuum chamber into which a sample ion ionized by the ion source is introduced, and a turbomolecular pump configured to maintain the vacuum chamber in a vacuum, in which the turbomolecular pump is provided above the vacuum chamber in a vertical direction.
Advantageous Effects of Invention
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According to the invention, a work space for maintenance or the like of a turbomolecular pump is secured as compared with one in the related art. Problems, configurations, and effects other than those described above will be clarified by description of the following embodiment.
Brief Description of Drawings
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- [FIG. 1] FIG. 1 is a diagram showing an outline of an analysis system including a plurality of mass spectrometers.
- [FIG. 2] FIG. 2 is a diagram showing an example of installation of the mass spectrometers.
- [FIG. 3] FIG. 3 is a diagram showing an outline of the mass spectrometer.
- [FIG. 4] FIG. 4 is a side view showing a state of the mass spectrometer during operation.
- [FIG. 5] FIG. 5 is a side view showing a state when a turbomolecular pump of the mass spectrometer is removed.
- [FIG. 6] FIG. 6 is a side view showing a state of a mass spectrometer according to Modification 1 during operation.
- [FIG. 7] FIG. 7 is a side view showing a state when a turbomolecular pump of the mass spectrometer according to Modification 1 is removed.
- [FIG. 8] FIG. 8 is a side view showing a state of a mass spectrometer according to Modification 2 during operation.
- [FIG. 9] FIG. 9 is a side view showing a state when a turbomolecular pump of the mass spectrometer according to Modification 2 is removed.
Description of Embodiments
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An embodiment of a mass spectrometer according to the invention will be described with reference to FIGS. 1 to 9. In the drawings used in the present description, the same or corresponding components are denoted by the same or similar reference signs, and repeated descriptions of these components may be omitted.
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First, an example of a schematic configuration and a use state of a mass spectrometer and a spectrometer system including the mass spectrometer will be described with reference to FIGS. 1 and 2. FIG. 1 is a diagram showing an outline of a spectrometer system including a plurality of mass spectrometers according to the embodiment, and FIG. 2 is a diagram showing an example of installation of the mass spectrometers according to the embodiment.
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A spectrometer system 1 shown in FIG. 1 includes a plurality of (three in FIG. 1) mass spectrometers 10 that ionize a sample and analyze ions according to a mass-to-charge ratio, and a control device 5 that is a part that controls operations of the mass spectrometers 10 and includes an operation unit that provides information to an operator and receives an input of an operation.
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As shown in FIG. 2, the spectrometer system 1 may be used in a state of being provided near a wall of an analysis chamber 100. In such a case, the control device 5 including the operation unit that provides information to the operator and receives an input of an operation is disposed at a position where the operation is most easily performed, and thus, in the three mass spectrometers 10, a work space for maintenance of each spectrometer or the like may be provided only on a front surface thereof. The same applies to a case of one mass spectrometer 10, and the same applies to a case where the spectrometer system 1 is not provided near the wall of the analysis chamber 100, and the work space may be provided only on the front surface or a rear surface thereof.
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Next, a configuration of the mass spectrometer 10 will be described with reference to FIGS. 3 to 9.
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First, a schematic configuration of the mass spectrometer 10 will be described with reference to FIG. 3. FIG. 3 is a diagram showing an outline of a mass spectrometer of an embodiment.
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The mass spectrometer 10 shown in FIG. 3 includes a housing 20 that supports components described later, an ion source 30, a vacuum chamber 40, a turbomolecular pump 50, a separation mechanism, and an exterior cover (not shown) that protects components other than the housing 20.
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The vacuum chamber 40 includes, inside thereof, an analysis unit (omitted for convenience of illustration) into which sample ions ionized by the ion source 30 are introduced and which analyzes the sample ions by mass-separating the sample ions, and differential evacuation is performed to gradually implement a vacuum from several 100 pascals since a degree of vacuum cannot be changed at once from an atmospheric pressure (atmospheric pressure at a position of the ion source 30) to a level of 10-3.
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The turbomolecular pump 50 is a pump for maintaining a space in the vacuum chamber 40 in a vacuum.
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The separation mechanism is a mechanism for mechanically separating an airtight member such as an O-ring made of a silicon resin for maintaining a connection portion between the vacuum chamber 40 and the turbomolecular pump 50 airtight, and includes a lever 60 provided on an exterior of the turbomolecular pump 50 provided above a top surface of the vacuum chamber 40 in a vertical direction, and elliptical fulcrums 65 provided at two locations of a connection portion between a base of the lever 60 and the turbomolecular pump 50.
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As shown in FIG. 3, the mass spectrometer 10 has a two-story structure in which the turbomolecular pump 50 is provided not on the housing 20 side but above the top surface of the vacuum chamber 40 in the vertical direction.
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The configuration of the mass spectrometer 10 is the same as that of a mass spectrometer in the related art except that the turbomolecular pump 50 is disposed above the vacuum chamber 40, and the details thereof are omitted.
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Next, how the turbomolecular pump is separated from the vacuum chamber will be described with reference to FIGS. 4 and 5. FIG. 4 is a side view showing a state of the mass spectrometer according to the embodiment during operation, and FIG. 5 is a side view showing a state of the mass spectrometer according to the embodiment when the turbomolecular pump is removed. FIGS. 4 and 5 show a state in which the exterior cover is excluded.
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As shown in FIG. 4, during an operation of the mass spectrometer 10, the lever 60 is in a state of being located on a front side of the device, and a longitudinal direction of the fulcrum 65 in which the base of the lever 60 is provided is in a state of being parallel to an upper surface of the vacuum chamber 40. Therefore, the airtight member that maintains the connection portion between the vacuum chamber 40 and the turbomolecular pump 50 in an airtight manner functions, and a degree of vacuum in the vacuum chamber 40 is maintained in a high state.
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At the time of maintenance or at the time of repair or replacement work due to a failure or the like of the turbomolecular pump 50, as shown in FIG. 5, when the turbomolecular pump 50 is removed, the exterior cover and the ion source 30 are first removed to access the turbomolecular pump 50.
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Next, by pushing the lever 60 to a back side of the mass spectrometer 10, an outer surface of the fulcrum 65 in the longitudinal direction interferes with the upper surface of the vacuum chamber 40, and the turbomolecular pump 50 is lifted upward. Therefore, even when the airtight member is fixed, the turbomolecular pump 50 can be easily detached from the upper surface of the vacuum chamber 40.
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After the maintenance is completed or after repair or replacement work, an unused airtight member is provided at the connection portion between the vacuum chamber 40 and the turbomolecular pump 50, and the vacuum chamber 40 and the turbomolecular pump 50 are fixed. Thereafter, the ion source 30 and the exterior cover are attached to complete the work.
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Next, another modification of the separation mechanism will be described with reference to FIGS. 6 to 9.
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First, a mass spectrometer 10A according to Modification 1 will be described with reference to FIGS. 6 and 7. FIG. 6 is a side view showing a state of a mass spectrometer according to Modification 1 during operation, and FIG. 7 is a side view showing a state when the turbomolecular pump of the mass spectrometer according to Modification 1 is removed. FIGS. 6 and 7 also show the state in which the exterior cover is excluded.
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A separation mechanism of the mass spectrometer 10A is constituted by a screw 70 and a plate 75 formed with a screw hole engaged with the screw 70, and one or more sets of plates 75 having threaded holes matching the screw 70 are attached to a side surface of the turbomolecular pump 50A.
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In the mass spectrometer 10A, as shown in FIG. 6, during an operation of the mass spectrometer 10A, a tip of the screw 70 is in a state of in contact with the upper surface of the vacuum chamber 40, and a lower end surface of a head of the screw 70 is not in contact with an upper surface of the plate 75. Therefore, the airtight member that maintains the connection portion between the vacuum chamber 40 and the turbomolecular pump 50A in the airtight manner functions, and the degree of vacuum in the vacuum chamber 40 is maintained in the high state.
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At the time of maintenance or at the time of repair or replacement work due to a failure or the like of the turbomolecular pump 50A, as shown in FIG. 7, the exterior cover and the ion source 30 are removed.
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Next, the screw 70 is turned to a tightening side. Accordingly, the screw 70 advances with respect to the plate 75, but since the tip of the screw 70 interferes with the upper surface of the top plate of the vacuum chamber 40, the turbomolecular pump 50A to which the plate 75 is fixed is lifted upward. Therefore, even when the airtight member is fixed, the turbomolecular pump 50A can be easily detached from the upper surface of the vacuum chamber 40.
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Next, a mass spectrometer 10B according to Modification 2 will be described with reference to FIGS. 8 and 9. FIG. 8 is a side view showing a state of a mass spectrometer according to Modification 2 of the embodiment during operation, and FIG. 9 is a side view showing a state when a turbomolecular pump of the mass spectrometer according to Modification 2 of the embodiment is removed. FIGS. 8 and 9 also show the state in which the exterior cover is excluded.
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A separation mechanism of the mass spectrometer 10B is constituted with a wedge 80, and a notch having a shape that substantially matches the wedge 80 is formed below a front surface side of the device of the turbomolecular pump 50B.
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In the mass spectrometer 10B, as shown in FIG. 8, during an operation of the mass spectrometer 10B, the wedge 80 does not enter the notch of the turbomolecular pump 50B, the airtight member that maintains the connection portion between the vacuum chamber 40 and the turbomolecular pump 50B in the airtight manner functions, and the degree of vacuum in the vacuum chamber 40 is maintained in the high state.
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At the time of maintenance or at the time of repair or replacement work due to a failure or the like of the turbomolecular pump 50B, as shown in FIG. 9, the exterior cover and the ion source 30 are removed.
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Next, the wedge 80 is pushed to a back side of the mass spectrometer 10B by a unit such a motor, a screw, or a cylinder, and the wedge 80 enters the notch of the turbomolecular pump 50B, so that the turbomolecular pump 50B is lifted from the upper surface of the vacuum chamber 40. Therefore, even when the airtight member is fixed, the turbomolecular pump 50B can be easily detached from the upper surface of the vacuum chamber 40.
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Next, effects of the present embodiment will be described.
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The mass spectrometers 10, 10A, 10B described above each include: the ion source 30; the vacuum chamber 40 into which the sample ions ionized by the ion source 30 are introduced; and the turbomolecular pumps 50, 50A, 50B configured to maintain the vacuum chamber 40 in a vacuum. The turbomolecular pumps 50, 50A, 50B are provided above the vacuum chamber 40 in the vertical direction.
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With such a configuration, since maintenance, replacement, and repair work of the turbomolecular pumps 50, 50A, 50B can be performed on the upper surface on front surface side of the device by removing the ion source 30, a work space for maintenance or the like of the turbomolecular pumps 50, 50A, 50B can be secured as compared with one in the related art, and the maintenance and the like can be easily performed in a limited area as compared with a configuration in the related art.
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In addition, since the separation mechanism for mechanically separating the airtight member for maintaining an airtight structure between the vacuum chamber 40 and the turbomolecular pumps 50, 50A, 50B is further provided, even when the airtight member is fixed between the vacuum chamber 40 and the turbomolecular pumps 50, 50A, 50B due to deterioration or the like, the vacuum chamber 40 and the turbomolecular pumps 50, 50A, 50B can be easily separated, and workability can be further improved.
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Further, since the separation mechanism includes the lever 60 and the fulcrum 65, or the screw 70 and the plate 75 formed with the screw hole engaged with the screw 70, or the wedge 80, the vacuum chamber 40 and the turbomolecular pumps 50, 50A, 50B can be reliably separated with a simple configuration.
<Others>
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The invention is not limited to the embodimentdescribed above, and various modifications and applications are possible. The embodiment described above is described in detail for easy understanding of the invention, and is not necessarily limited to those having all the configurations described above.
Reference Signs List
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- 1: spectrometer system
- 5: control device
- 10, 10A, 10B: mass spectrometer
- 20: housing
- 30: ion source
- 40: vacuum chamber
- 50, 50A, 50B: turbomolecular pump
- 60: lever (separation mechanism)
- 65: fulcrum (separation mechanism)
- 70: screw (separation mechanism)
- 75: plate (separation mechanism)
- 80: wedge (separation mechanism)
- 100: analysis chamber