MULTIPOLE WITH MOUNTING RINGS ARRANGED ON THE END FACES THEREOF, AND MOUNTING RING OF SAID TYPE

Abstract

A multipole with mounting rings arranged on its end faces for mounting the multipole in a mass spectrometer includes two electrode half-shells each having at least two electrodes joinable together by positive-fitting connections on the electrode half-shell longitudinal edges. Each positive-fitting connection includes a fitting and a matching mating fitting, the fitting integrally formed on one electrode half-shell and the mating fitting integrally formed on the other electrode half-shell. Each mounting ring has two mounting ring fittings. One mounting ring fitting can be joined to a mating fitting integrally formed on one of the two electrode half-shells and the other of the two mounting ring fittings can be joined to a mating fitting integrally formed on the other of the two electrode half-shells. Furthermore, a mounting ring for such a multipole has two mounting ring fittings joinable to corresponding mating fittings integrally formed on the electrode half-shells.

Claims

1: A multipole with mounting rings arranged on its end faces for mounting the multipole in a mass spectrometer, wherein the multipole comprises two electrode half-shells each having at least two electrodes which can be joined together by positive-fitting connections arranged on the longitudinal edges of the electrode half-shells, wherein each positive-fitting connection comprises a fitting and a mating fitting matched thereto, the fitting being integrally formed on one of the two electrode half-shells and the mating fitting being integrally formed on the other of the two electrode half-shells, wherein each of the mounting rings has two mounting ring fittings, wherein one of the two mounting ring fittings can be joined to a mating fitting integrally formed on one of the two electrode half-shells and the other of the two mounting ring fittings can be joined to a mating fitting integrally formed on the other of the two electrode half-shells.

2: The multipole according to claim 1, wherein the mating fitting, which can be joined to a mounting ring, of one of the electrode half-shells is part of one of the positive-fitting connections for joining together the two electrode half-shells.

3: The multipole according to claim 1, wherein the mating fitting, which can be joined to a mounting ring, of one of the electrode half-shells is formed separately from the mating fittings of the electrode half-shells provided for the positive-fitting connections for joining together the two electrode half-shells.

4: The multipole according to claim 1, wherein the fittings each have a roof structure and the mating fittings each have a prism structure, so that each fitting and the mating fitting joined to it each form a roof-and-prism connection.

5: The multipole according to claim 1, wherein each fitting can be screwed to the mating fitting joined to it by means of a screw in order to form a screw connection.

6: The multipole according to claim 1, wherein each electrode half-shell on a longitudinal edge comprises a plurality, preferably three, of mating fittings, wherein the two outer mating fittings each have two drilled holes for screws, wherein each of the two outer screws can be screwed to another of the two mounting ring fittings.

7: The multipole according to claim 6, wherein the fittings on the electrode half-shells and the mounting ring fittings each have a threaded hole for receiving one of the screws.

8: A mounting ring for a multipole according to claim 1, wherein the mounting ring has two mounting ring fittings which are designed in such a way as to be joined to correspondingly designed mating fittings integrally formed on the electrode half-shells.

9: The mounting ring according to claim 8, wherein the mounting ring fittings are integrally formed on the respective mounting ring in a rotationally symmetric manner.

10: The mounting ring according to claim 9, wherein the mounting ring fittings are arranged to be rotationally symmetric by 180°.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Other objects and features of the invention will become apparent from the following detailed description considered in connection with the accompanying drawings. It is to be understood, however, that the drawings are designed as an illustration only and not as a definition of the limits of the invention.

[0034] In the drawings,

[0035] FIG. 1 an exploded view of a multipole including mounting rings according to the prior art,

[0036] FIG. 2 a perspective view of the multipole shown in FIG. 1 in the assembled state with the mounting rings,

[0037] FIG. 3 a perspective view of the multipole shown in FIG. 1, in the assembled state without mounting rings,

[0038] FIG. 4 an exemplary embodiment of a multipole according to the invention in an exploded view,

[0039] FIG. 5 a perspective view of the multipole shown in FIG. 4 in the assembled state with the mounting rings, and

[0040] FIG. 6 a perspective view of the multipole shown in FIG. 4, in the assembled state without mounting rings.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0041] FIGS. 1 to 3 have already been described above. The statements made there for the definition of terms also apply to the following description of an exemplary embodiment according to the invention.

[0042] FIGS. 4 to 6 show an exemplary embodiment of a multipole 110 according to the invention with mounting rings 112, 114 attached to the end faces of the multipole 110 for mounting the multipole 110 in a mass spectrometer, not illustrated. FIG. 4 shows an exploded view of this multipole 110 together with the two mounting rings 112, 114. FIG. 5 shows a perspective view of the assembled multipole 110 together with the mounting rings 112, 114 according to FIG. 4. FIG. 6 shows a perspective view of the assembled multipole 100, but with the mounting rings 112, 114 removed.

[0043] The multipole 110 comprises two electrode half-shells 116, 118. Each of these electrode half-shells 116, 118 has a plurality, namely in the example two, of rod-shaped electrodes 120, 122 and 124, 126. Each pair of these electrodes 120, 122 or 124, 126 is fixed on a carrier 128, 130, connected together by insulating bodies 132, 136, 138. These insulating bodies 132, 136, 138 electrically insulate the electrodes 120, 122, 124, 126 from the carriers 128, 130. For example, the insulating bodies 132, 136, 138 can be made of quartz or quartz glass.

[0044] Each of the carriers 128, 130 is essentially shaped like a half-hollow cylinder fitted with recesses and holes, i.e. a hollow cylinder cut open lengthwise. These carriers 128, 130 are made of metal or a metal alloy and are electrically conductive and have a specified wall thickness.

[0045] The electrodes 120, 122, 124, 126 in the illustrated exemplary embodiment are each designed in three parts. They each have a longer central section and two shorter outer sections. The outer sections are used, for example, to form a pre-filter and a post-filter. Alternatively, the electrodes 120, 122, 124, 126 (contrary to the exemplary embodiment shown) can each be designed as one piece.

[0046] The lower electrode half-shell 116 can be joined to the upper electrode half-shell 118 via positive-fitting connections 140, 142, 144, arranged along the longitudinal edges 146, 148, 150, 152 of the electrode half-shells 116, 118. As already mentioned above, these longitudinal edges 146, 148, 150, 152 form narrow surfaces, the width of which corresponds to the wall thickness of the carriers 128, 130.

[0047] Analogous to FIGS. 1 to 3, in FIGS. 4 to 6 the positive connections 140, 142, 144 are also only designated along the frontal longitudinal edges 146, 150 for reasons of presentation, however, corresponding positive-fitting connections are also provided along the rear longitudinal edges 148, 152. Each of these positive-fitting connections 140, 142, 144 shown as well as the non-illustrated positive-fitting connections comprises a fitting 154, 156, 158 with a roof structure on the lower electrode half-shell 116 and a mating fitting 160, 162, 164 matched to it that has a prism structure on the upper electrode half-shell 118.

[0048] The electrode half-shells 116, 118 are structured and shaped in the same way. Therefore, the lower electrode half-shell 116 on its rear longitudinal axis 148 also has mating fittings 166, 168, 170, which are integrally formed with corresponding fittings (not visible in FIGS. 4 to 6) on the rear longitudinal edge 152 of the upper electrode half-shell 118 and in each case form pairs of further positive-fitting connections (not separately designated). These positive-fitting connections are secured with screws 172, 174, 176, 178, 180, 182.

[0049] A mounting ring 112 is provided on the front end face 184. A mounting ring 114 is provided on the rear end face 186 in the same way. The mounting of these mounting rings 112, 114 on the multipole 110 differs considerably from the prior art according to FIGS. 1 to 3. Namely, two mounting ring fittings 190, 194, 196 are provided on each of the mounting rings 112, 114. For each of the mounting rings 112, 114, one of its two mounting ring fittings 190, 194 respectively can be joined to a mating fitting 160 or 164, integrally formed on one of the two electrode half-shells 118, and the other of the two mounting ring fittings 196 can be joined to a mating fitting 166, 170 integrally formed on the other of the two electrode half-shells 118.

[0050] The mating fitting 160 of the electrode half-shell 118, which can be joined to the mounting ring fitting 190 of the mounting ring 112, is part of the positive-fitting connection 140 with which the two electrode half-shells 116, 118 are joined together. A further, not shown, mounting ring fitting of the mounting ring 112 is joined together with the mating fitting 166 of the electrode half-shell 116 and is also part of a positive connection between the two electrode half-shells 116, 118.

[0051] In the same way, the mating fitting 164 of the electrode half-shell 118, which can be joined to the mounting ring fitting 194 of the mounting ring 114, is part of the positive-fitting connection 144 with which the electrode half-shells 116, 118 are connected. The further mounting ring fitting 196 of the mounting ring 114 is joined to the mating fitting 170 of the electrode half-shell 118 and is also part of a positive-fitting connection between the two electrode half-shells 116, 118.

[0052] These positive-fitting connections between the mounting rings 112, 114 and the electrode half-shells 116, 118 are secured with screws 198, 200, 202, 204 to form screw connections. Additional drilled holes 206, 208, 210, 212 are provided in the mating fittings 160, 164, 166, 170 for this purpose, through which holes these screws 198, 200, 202, 204 are passed. The mounting ring fittings 190, 194, 196 of the mounting rings 112, 114 have threaded holes for receiving these screws 198, 200, 202, 204.

[0053] The mounting fittings 190, 194, 196 of the mounting rings 112, 114 each have a roof structure and can be joined to matching prism structures of the mating fittings 160, 164, 166, 170 to form roof-and-prism connections.

[0054] As stated above, a positive-fitting connection is a connection which excludes a relative displacement of two components at least in one dimension, so that the positive connections described in this document are formed by a fitting with a mating fitting in such a way that, after being joined to the electrode half-shells 116, 118, the mounting rings 112, 114 can be moved in the longitudinal direction of the multipole 110 until the screws 172, 174, 176, 178, 180, 182 are installed. However, such a displacement of the electrode half-shells 116, 118 and the mounting rings 112, 114 in the radial direction of the multipole 110 is then also not possible, on account of these positive-fitting connections. After these screws are tightened, the longitudinal displacements of the multipole 110 are also excluded.

[0055] The fixing according to the invention of the mounting rings 112, 114 to the multipole 110 contributes to enabling the alignment and positioning of the multipole 110 in a mass spectrometer with very high accuracy, since the surfaces of the roof structures and prism structures can be produced with very high accuracy and at the same time with little effort. The prism structures of the mating fittings 160, 164, 166, 170 on the electrode half-shells 116, 118 are ground together with the electrodes, wherein this grinding is a highly accurate machining process with an accuracy in the range of a few microns. While the surfaces of the mounting ring fittings 190, 194, 196 of the mounting rings 112, 114 cannot be ground at the same time, they can also be machined with high precision in a separate processing step.

[0056] Overall, the invention therefore allows mounting rings to be provided for mounting a multipole in a mass spectrometer, which ensure a high accuracy of the positioning and alignment of the multipole in the mass spectrometer.

[0057] Although only a few embodiments of the present invention have been shown and described, it is to be understood that many changes and modifications may be made thereunto without departing from the spirit and scope of the invention.

[0058] The figures use the following reference numbers: [0059] 10, 110 multipole [0060] 12, 112 mounting ring [0061] 14, 114 mounting ring [0062] 16, 116 electrode half-shell [0063] 18, 118 electrode half-shell [0064] 20, 120 electrode [0065] 22, 122 electrode [0066] 24, 124 electrode [0067] 26, 126 electrode [0068] 28, 128 carrier [0069] 30, 130 carrier [0070] 32, 132 insulating body [0071] 36, 136 insulating body [0072] 38, 138 insulating body [0073] 40, 140 positive-fitting connection [0074] 42, 142 positive-fitting connection [0075] 44, 144 positive-fitting connection [0076] 46, 146 longitudinal edge [0077] 48, 148 longitudinal edge [0078] 50, 150 longitudinal edge [0079] 52, 152 longitudinal edge [0080] 54, 154 fitting [0081] 56, 156 fitting [0082] 58, 158 fitting [0083] 60, 160 mating fitting [0084] 62, 162 mating fitting [0085] 64, 164 mating fitting [0086] 66, 166 mating fitting [0087] 68, 168 mating fitting [0088] 70, 170 mating fitting [0089] 72, 172 screw [0090] 74, 174 screw [0091] 76, 176 screw [0092] 78, 178 screw [0093] 80, 180 screw [0094] 82, 182 screw [0095] 84, 184 end face [0096] 86, 186 end face [0097] 88 clamping lug [0098] 190 mounting ring fitting [0099] 194 mounting ring fitting [0100] 196 mounting ring fitting [0101] 198 screw [0102] 200 screw [0103] 202 screw [0104] 204 screw [0105] 206 drilled hole [0106] 208 drilled hole [0107] 210 drilled hole [0108] 212 drilled hole