Mass spectrometer

Abstract

A mass spectrometer (10), (10A), (10B) is provided with: an ion source (30); a vacuum chamber (40) into which the sample ionized by the ion source (30) is introduced; and turbo molecular pumps (50), (50A), (50B) that hold the vacuum chamber (40) in a vacuum state, the turbo molecular pumps (50), (50A), (50B) being provided above the vacuum chamber (40) in the vertical direction.

Description

Technical Field

[0001] The present invention relates to a mass analysis device. Background Art

[0002] Typically, a mass spectrometer includes components such as an ion source, an ion lens, a quadrupole mass filter, and an ion detector within a vacuum chamber. A technique using a turbomolecular pump to maintain a high vacuum state within the vacuum chamber has been disclosed (see Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2020-13737 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] In the mass spectrometer disclosed in Patent Document 1 and the like, the vacuum chamber is supported by a frame structure. Here, the frame structure is a structure composed of a plurality of frame members such as columns and beams.

[0008] The turbomolecular pump is mounted on, for example, a side wall or a bottom portion of the vacuum chamber. Since the vacuum chamber and the turbomolecular pump are heavy, the frame structure is made by joining a plurality of frame members.

[0009] Regular maintenance and repair of turbomolecular pumps in the event of a malfunction require a relatively large workspace. This is especially true when multiple mass spectrometers are installed in a confined space or when mass spectrometers are located near walls, as the area available for workspace is limited. Therefore, ensuring efficient maintenance becomes a challenge.

[0010] The present invention provides a mass spectrometer capable of ensuring a larger working space for maintenance of a turbomolecular pump than in the past.

[0011] Means for solving problems

[0012] The present invention includes multiple means for solving the above-mentioned problems. For example, it comprises: an ion source; a vacuum chamber into which sample ions ionized by the ion source are introduced; and a turbomolecular pump that maintains the vacuum chamber in a vacuum, wherein the turbomolecular pump is arranged vertically above the vacuum chamber.

[0013] Effects of the Invention

[0014] According to the present invention, compared with the related art, it is possible to ensure a work space for maintenance of the turbomolecular pump, etc. Other problems, structures, and effects than those described above will become clear from the following description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a diagram showing an overview of an analysis system including a plurality of mass spectrometers.

[0016] Figure 2 This is a diagram showing an example of the installation of a mass spectrometer.

[0017] Figure 3 A diagram showing an overview of a mass spectrometer.

[0018] Figure 4 It is a side view showing the mass spectrometer in operation.

[0019] Figure 5 This is a side view showing a state in which the turbomolecular pump of the mass spectrometer is removed.

[0020] Figure 6 This is a side view showing the mass spectrometer according to Modification 1 during operation.

[0021] Figure 7 This is a side view showing the state of the mass spectrometer of Modification 1 when the turbomolecular pump is removed.

[0022] Figure 8 This is a side view showing the mass spectrometer according to Modification 2 during operation.

[0023] Figure 9 This is a side view showing a state in which the turbomolecular pump of the mass spectrometer of Modification 2 is removed. DETAILED DESCRIPTION

[0024] use Figures 1 to 9 In the drawings used in this specification, identical or corresponding components are denoted by identical or similar reference numerals, and overlapping descriptions of these components may be omitted.

[0025] First use Figure 1 as well as Figure 2 An example of a schematic configuration and usage of a mass spectrometer or an analysis system including the mass spectrometer will be described. Figure 1 is a diagram showing an overview of an analysis system including mass spectrometers according to a plurality of embodiments. Figure 2 This is a diagram showing an example of the installation of a mass spectrometer according to the embodiment.

[0026] Figure 1 The analysis system 1 shown has: a plurality of ( Figure 1There are three mass spectrometers 10 (three in total) that ionize the sample and analyze the ions based on the mass-to-charge ratio; and a control device 5 that has an operating unit that controls the operation of these mass spectrometers 10 and is used to receive information or operation input for the operator.

[0027] like Figure 2 As shown, such an analysis system 1 is sometimes used while installed on a wall of an analysis chamber 100. In this case, in order to position the control device 5, which includes an operating unit for receiving operator information and operational input, in the most accessible position, the three mass analyzers 10 may only have workspaces for maintenance, etc., located on their front surfaces. This also applies to the case of a single mass analyzer 10. Furthermore, if the analysis system 1 is not installed on a wall of the analysis chamber 100, workspaces may only be provided on its front and rear surfaces.

[0028] Next, use Figures 3 to 9 The configuration of the mass spectrometer 10 will be described.

[0029] First, use Figure 3 The schematic configuration of the mass spectrometer 10 will be described. Figure 3 It is a diagram showing an overview of a mass spectrometer according to an embodiment.

[0030] Figure 3 The mass spectrometer 10 shown includes a housing 20 that supports various structures 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 structures other than the housing 20 .

[0031] The vacuum chamber 40 has an analysis unit (omitted for ease of illustration) inside thereof. The analysis unit is fed with sample ions ionized by the ion source 30 and analyzes the sample ions by mass separation. Since it is impossible to change the pressure from atmospheric pressure (the pressure at the location of the ion source 30) to 10 -3 To achieve a horizontal vacuum degree, differential exhaust is performed in a manner that gradually achieves vacuum from several hundred Pascals.

[0032] The turbomolecular pump 50 is a pump for maintaining the space in the vacuum chamber 40 at a vacuum state.

[0033] The separation mechanism is a mechanism for mechanically separating an airtight member such as an O-ring formed of silicone resin, which is used to maintain the connection between the vacuum chamber 40 and the turbomolecular pump 50 in an airtight manner. The mechanism comprises a rod 60 provided on the exterior of the turbomolecular pump 50, which is provided on the top surface vertically above the vacuum chamber 40, and elliptical levers 65 provided at the base of the rod 60 and at the connection portions with two locations of the turbomolecular pump 50.

[0034] like Figure 3 As shown, the mass spectrometer 10 has a two-layer structure in which the turbomolecular pump 50 is not provided on the housing 20 side but is provided on the top surface of the vacuum chamber 40 in the vertical direction.

[0035] The configuration of the mass spectrometer 10 is the same as that of a conventional mass spectrometer except that the turbomolecular pump 50 is disposed above the vacuum chamber 40 , and detailed description thereof will be omitted.

[0036] Next, use Figure 4 as well as Figure 5 The following describes the situation when the turbomolecular pump is disconnected from the vacuum chamber. Figure 4 is a side view showing the mass spectrometer of the embodiment in operation. Figure 5 This is a side view showing the situation when the turbomolecular pump of the mass spectrometer of the embodiment is removed. Figure 4 as well as Figure 5 Indicates the state where the outer cover is removed.

[0037] like Figure 4 As shown, during operation of the mass spectrometer 10, the rod 60 is positioned toward the front of the device, and the long axis of the lever 65 provided at the base of the rod 60 is parallel to the upper surface of the vacuum chamber 40. Therefore, the airtight member that maintains an airtight connection between the vacuum chamber 40 and the turbomolecular pump 50 is functioning, and the vacuum level within the vacuum chamber 40 is maintained at a high level.

[0038] During maintenance or repair or replacement work caused by failure of the turbo molecular pump 50, such as Figure 5 As shown, when removing the turbomolecular pump 50 , first, the outer cover and the ion source 30 are removed in order to access the turbomolecular pump 50 .

[0039] Next, by pushing the rod 60 toward the rear of the mass spectrometer 10, the outer surface of the lever 65 in the longitudinal direction interferes with the upper surface of the vacuum chamber 40, thereby lifting the turbomolecular pump 50 upward. Therefore, even when an airtight member is fixed, the turbomolecular pump 50 can be easily and simply peeled off from the upper surface of the vacuum chamber 40.

[0040] After maintenance, repair, or replacement, an unused airtight member is placed at the connection between the vacuum chamber 40 and the turbomolecular pump 50, and the vacuum chamber 40 and the turbomolecular pump 50 are fixed. The ion source 30 and the outer cover are then installed to complete the operation.

[0041] Next, use Figures 6 to 9 Other modifications of the separation mechanism will be described.

[0042] First, use Figure 6 as well as Figure 7 A mass spectrometer 10A according to Modification 1 will be described. Figure 6 is a side view showing the mass spectrometer of Modification 1 in operation. Figure 7 This is a side view showing the situation when the turbomolecular pump of the mass spectrometer of Modification 1 is removed. Figure 6 as well as Figure 7 Also indicates the state with the exterior cover removed.

[0043] The separation mechanism of the mass spectrometer 10A is composed of screws 70 and plates 75 having threaded holes for engagement with the screws 70 . One or more plates 75 having screw blocking holes aligned with the screws 70 are attached to the side surface of the turbomolecular pump 50A.

[0044] In the mass spectrometer 10A, as Figure 6 As shown, during operation of the mass spectrometer 10A, the tip of the screw 70 is in contact with the upper surface of the vacuum chamber 40, and the lower end of the screw 70 is not in contact with the upper surface of the plate 75. Therefore, the airtight member that maintains an airtight connection between the vacuum chamber 40 and the turbomolecular pump 50A is functioning, and the vacuum level within the vacuum chamber 40 is maintained at a high level.

[0045] During maintenance or repair or replacement of the turbo molecular pump 50A, Figure 7 As shown, the outer cover and the ion source 30 are removed.

[0046] Next, screw 70 is turned toward the tightening side. This allows screw 70 to advance relative to plate 75, but the tip of screw 70 interferes with the upper surface of the ceiling of vacuum chamber 40, causing turbomolecular pump 50A, to which plate 75 is fixed, to lift upward. Therefore, even when an airtight member is fixed, turbomolecular pump 50A can be easily peeled off from the upper surface of vacuum chamber 40.

[0047] Next, use Figure 8 as well as Figure 9 A mass spectrometer 10B according to Modification 2 will be described. Figure 8is a side view showing a mass spectrometer according to a second modification of the embodiment in operation. Figure 9 This is a side view showing the situation when the turbomolecular pump of the mass spectrometer of the modified example 2 of the embodiment is removed. Figure 8 as well as Figure 9 Also indicates the state with the exterior cover removed.

[0048] The separation mechanism of the mass spectrometer 10B is constituted by a wedge 80 , and a cutout roughly conforming to the shape of the wedge 80 is formed below the front surface of the turbomolecular pump 50B.

[0049] In the mass spectrometer 10B, as Figure 8 As shown, during the operation of the mass spectrometer 10B, the wedge 80 does not intrude into the cutout of the turbomolecular pump 50B, and the airtight member that maintains the connection between the vacuum chamber 40 and the turbomolecular pump 50B airtightly functions, and the vacuum degree in the vacuum chamber 40 is maintained at a high level.

[0050] During maintenance or repair or replacement of the turbomolecular pump 50B, Figure 9 As shown, the outer cover and the ion source 30 are removed.

[0051] Next, the wedge 80 is pushed toward the rear side of the mass spectrometer 10B by a mechanism such as a motor, a screw, or a cylinder, so that the wedge 80 penetrates the cutout of the turbomolecular pump 50B, thereby lifting the turbomolecular pump 50B from the upper surface of the vacuum chamber 40. Therefore, even when an airtight member is fixed, the turbomolecular pump 50B can be easily and simply peeled off from the upper surface of the vacuum chamber 40.

[0052] Next, the effects of this embodiment will be described.

[0053] The mass spectrometers 10, 10A, and 10B described above include an ion source 30, a vacuum chamber 40 into which sample ions ionized by the ion source 30 are introduced, and turbomolecular pumps 50, 50A, and 50B for maintaining the vacuum chamber 40 in a vacuum state. The turbomolecular pumps 50, 50A, and 50B are disposed vertically above the vacuum chamber 40.

[0054] According to such a structure, by removing the ion source 30, maintenance, replacement or repair of the turbomolecular pumps 50, 50A, 50B can be performed on the upper surface of the front surface side of the device, so compared with the past, the working space for maintenance of the turbomolecular pumps 50, 50A, 50B can be ensured, and compared with the previous structure, maintenance can be easily performed in a limited area.

[0055] Furthermore, since a separation mechanism is provided for mechanically separating the airtight member for maintaining the airtight structure between the vacuum chamber 40 and the turbomolecular pumps 50, 50A, and 50B, even if the airtight member becomes fixed between the vacuum chamber 40 and the turbomolecular pumps 50, 50A, and 50B due to deterioration or the like, the vacuum chamber 40 and the turbomolecular pumps 50, 50A, and 50B can be easily separated, thereby further improving operability.

[0056] Furthermore, the separation mechanism includes the rod 60 and the lever 65 , the screw 70 and the plate 75 having a threaded hole for engaging with the screw 70 , or the wedge 80 , thereby reliably separating the vacuum chamber 40 from the turbomolecular pumps 50 , 50A, 50B with a simple structure.

[0057] <Other>

[0058] It should be noted that the present invention is not limited to the above-described embodiments, and various modifications and applications are possible. The above-described embodiments are described in detail to facilitate understanding of the present invention, and are not limited to necessarily having all the described structures.

[0059] Description of reference numerals:

[0060] 1…Analysis system

[0061] 5…Control device

[0062] 10, 10A, 10B…Mass analysis device

[0063] 20…frame

[0064] 30…Ion source

[0065] 40…Vacuum chamber

[0066] 50, 50A, 50B… turbomolecular pumps

[0067] 60... rod (release mechanism)

[0068] 65…Lever (release mechanism)

[0069] 70…Screw (Separation mechanism)

[0070] 75… Plate (separation mechanism)

[0071] 80…Wedge (separation mechanism)

[0072] 100…Analysis room.

Claims

1. A mass spectrometer, wherein: The mass analysis device comprises: ion source; a vacuum chamber into which sample ions ionized by the ion source are introduced; and a turbomolecular pump to maintain the vacuum chamber at a vacuum, The turbomolecular pump is arranged above the vacuum chamber in a vertical direction.

2. The mass spectrometer according to claim 1, wherein The mass spectrometer further includes a separation mechanism that mechanically separates an airtight member for maintaining an airtight structure between the vacuum chamber and the turbomolecular pump.

3. The mass spectrometer according to claim 2, wherein The separation mechanism includes a rod and a lever.

4. The mass spectrometer according to claim 2, wherein The separation mechanism includes a screw and a plate having a threaded hole formed therein to engage with the screw.

5. The mass spectrometer according to claim 2, wherein The separation mechanism has a wedge.

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