Dry vacuum pump and method of manufacturing the same

Abstract

A dry vacuum pump (1) comprising: - a stator (2) comprising at least one first and at least one second complementary half-shells (7, 8), each half-shell (7, 8) comprising at least one half-partition (13e) which, with a half-partition (14a-14e) of the other half-shell (8), forms a separation partition between two successive pump chambers of a pump stage (3a-3f) mounted in series between a suction mouth (4) and a discharge mouth (5) of said vacuum pump (1), - two rotor shafts (6) configured to rotate in counter-rotation in said pump chambers, characterized in that at least one half-partition (13e, 14d, 14e) of a half-shell (7, 8) is assembled in a support (15) of said half-shell (7, 8) by assembly.

Description

Technical Field

[0001] This invention relates to a dry vacuum pump, particularly a multi-stage dry vacuum pump, such as a Roots-type or claw-type vacuum pump. The invention also relates to a method for manufacturing such a vacuum pump. Background Technology

[0002] Dry multistage vacuum pumps consist of multiple pump stages connected in series, in which the gas to be pumped circulates between the suction port and the discharge port. Distinguishing known vacuum pumps include vacuum pumps with rotating vanes, also known as "Roots" vacuum pumps, or vacuum pumps with a beak, also known as "claw" vacuum pumps. These vacuum pumps are called "dry" because, during operation, the rotors rotate inside the stator, and there is no mechanical contact between the rotors or between the rotor and the stator, thus allowing the absence of oil in these pump stages.

[0003] In some pumping applications, such as those used in the semiconductor, flat panel display, photovoltaic, and coating industries, the gases used may be corrosive, and process residues may include abrasive powders that can damage all or part of the static parts, especially the static parts of high-pressure pump stages, which are also the parts with the smallest axial operating clearances.

[0004] Multistage vacuum pumps with a sliced ​​architecture—that is, their stators are formed by axially assembling stator elements—solve this problem relatively well. In fact, their disassembly makes them easy to clean, and their discretization allows damaged parts to be replaced without replacing the entire stator. This corresponds to the rather complex assembly of the vacuum pumps, requiring numerous positioning and fixing components as well as sealing components between each interface. This leads to increased manufacturing costs for parts and consequently, increased labor costs.

[0005] Multistage vacuum pumps with a half-shell architecture, as described, for example, in US 6,572,351B2, make it possible to reduce these costs. However, these pumps can be disadvantageous during maintenance because even if only part of the half-shell is damaged, one or all of the half-shells must be replaced. Furthermore, the cost of obtaining the half-shell is relatively high due to the machining precision required to manufacture the pump chamber and its partitions.

[0006] Another issue related to the semi-shell architecture is inherent to machining constraints. In fact, machining requires the use of specialized milling cutters, and due to the large amount of material to be milled, it demands a relatively long machining time. The diameter of the shaft passage determines the shank diameter of the cutter set, and the ratio between the shaft passage and the pump chamber diameter may or may not allow the use of combination tools. The bending stiffness of the cutter set, related to these constraints, determines the geometry of the chamber and partition, and the width of the thinnest pump chamber determines the width of the cutter used to cut it. Indeed, seeking compromises between these technical production constraints and design constraints sometimes results in the inability to manufacture thin pump chambers. Summary of the Invention

[0007] One object of the present invention is to overcome at least partially any of the above-mentioned disadvantages.

[0008] Therefore, the subject of this invention is a dry vacuum pump, which includes:

[0009] - A stator comprising at least one first and at least one second complementary half-shell, each half-shell including at least one half-partition that engages with a half-partition of the other half-shell to form a partition between two consecutive pump chambers of a pump stage mounted in series between the suction port and the discharge port of a vacuum pump.

[0010] - Two rotor shafts configured to rotate synchronously in opposite directions within the pump chamber.

[0011] The feature is that at least one half-partition of the half-shell is assembled in the support of the half-shell.

[0012] The half-shell is therefore easier to manufacture, especially compared to a bracket that can be machined from the front without contour milling, which reduces production costs. Furthermore, this architecture allows for the manufacture of pump chambers with narrow axial dimensions, without being limited by the size of the production tools.

[0013] The vacuum pump may also include one or more of the features described below.

[0014] At least one of the half-partitions can be assembled into the bracket via a detachable assembly. Therefore, in the event of blockage or damage, a portion of the half-shell can be easily removed for cleaning or replacement, thus reducing maintenance costs.

[0015] The at least one half-partition can be fixed to the bottom of the half-chamber, which is detachably fitted into the support of the half-shell. The bottom of the half-chamber and the at least one half-partition are formed in a removable insert of the half-shell. Because the insert is removable, it can be separated from the support to clean the bottom of the half-chamber.

[0016] At least one half-shell may include:

[0017] - At least one removable fixing component, such as a screw, is used to secure the removable half-partition to the bracket, and / or

[0018] - At least one positioning element, such as a pin or key, is used to position the removable half-partition in the bracket.

[0019] The half-shell may include at least one insert carrying the at least one half-partition, the insert having a fixed half-flange, the at least one fixing member and / or the at least one positioning member being inserted, for example, axially into the fixed half-flange and the bracket and / or another fixed flange.

[0020] The at least one fixing member and / or the at least one positioning member can be radially inserted into the bracket through the removable semi-partition.

[0021] The vacuum pump may include at least one interstage channel configured to connect the outlet of a previous pump stage to the inlet of a subsequent pump stage. At least a portion of the interstage semi-channel is formed in an insert of a half-shell and has an opening on the side of the insert, which carries a half-partition and is assembled in a support via a removable assembly. This facilitates access to the interior of the interstage channel, simplifying its cleaning and manufacturing. Another advantage of forming the interstage channel in a removable insert is that it allows for the formation of very narrow channels.

[0022] The at least one interstage semi-channel may be formed in a fixed semi-flange on one side of the semi-partition, which also allows the insert to be fixed to the bracket.

[0023] The vacuum pump may include two interstage semi-channels partially formed in the side of at least one insert, the interstage semi-channels being located on both sides of a semi-partition.

[0024] At least one half-partition can be assembled in the bracket by pressure assembly (i.e., press fitting).

[0025] The vacuum pump may include at least one interstage channel configured to connect the outlet of a previous pump stage to the inlet of a subsequent pump stage, at least a portion of the interstage half-channel being formed in an insert of a half-shell and having an opening on the side of the insert, the insert carrying a half-partition and being assembled in a support by pressure fitting.

[0026] The at least one half-partition assembled by assembly, or at least one insert carrying the at least one half-partition, may be made of a material or have a coating that is, for example, a material or coating containing nickel, which is more corrosion-resistant and / or wear-resistant than the material or coating of the body of the half-shell, such as cast iron. More durable materials or coatings are generally also the most expensive, thus limiting their application to components assembled by assembly allows for the restriction of their use to the half-shell components most vulnerable to external attack.

[0027] At least one half-partition that is joined to at least one half-partition assembled by assembly can also be assembled by assembly.

[0028] At least one half-shell may include at least two half-partitions assembled together, which engage with two half-partitions assembled together in another half-shell to separate three consecutive pump chambers.

[0029] The half-shell separating the pump chambers of the last pump stage and the penultimate pump stage can be assembled.

[0030] The half-shell separating the pump chambers of the penultimate and penultimate pump stages can be assembled.

[0031] Preferably, the pump stage located on the discharge side of the vacuum pump, that is, the pump stage located on the highest pressure side where the risk of corrosion and wear is greatest and the narrowest, is assembled in a bracket.

[0032] At least one half-shell may include at least one half-partition that can be assembled by a detachable assembly, and at least one non-detachable half-partition.

[0033] The at least one non-removable half-partition is, for example, formed in the body of the half-shell, or assembled in a support by pressure fitting.

[0034] The non-removable semi-partitions are, for example, those located between the first pump stages where the pressure is lowest and the risk of corrosion or wear is lowest. The non-removable semi-partitions allow for the retention of advantages such as time savings during assembly and reduced need for fixing and positioning components in the semi-shell structure.

[0035] The half-partition that is joined to the non-removable half-partition can also be non-removable.

[0036] Another subject of the invention is a method for manufacturing a dry vacuum pump, wherein at least one half-partition of a half-shell is assembled in a support of the half-shell by means of detachable assembly or pressure assembly. Attached Figure Description

[0037] Other advantages and features will become apparent after reading the following description of specific, but not limiting, embodiments of the invention, along with the accompanying drawings, in which:

[0038] [ Figure 1 ] Figure 1 This is an assembly view of the stator of a dry vacuum pump according to a first exemplary embodiment.

[0039] [ Figure 2 ] Figure 2 yes Figure 1A perspective view of an example of the rotor shaft of a vacuum pump.

[0040] [ Figure 3 ] Figure 3 yes Figure 1 A view of the stator, with the half-shell in a disassembled state.

[0041] [ Figure 4 ] Figure 4 yes Figure 3 Exploded view of the stator.

[0042] [ Figure 5 ] Figure 5 yes Figure 1 A perspective view of one half of the stator shell.

[0043] [ Figure 6 ] Figure 6 yes Figure 1 A perspective view of the other half of the stator shell.

[0044] [ Figure 7 ] Figure 7 This is a perspective view of two assembled, detachable half-partitions.

[0045] [ Figure 8 ] Figure 8 yes Figure 7 The assembled half-partition is rotated 180° to view.

[0046] [ Figure 9A ] Figure 9A A first variation of a second embodiment of the removable half-shell is shown, as viewed in cross-section.

[0047] [ Figure 9B ] Figure 9B The second variant is shown to be similar to Figure 9A The view.

[0048] [ Figure 10A ] Figure 10A The third variant embodiment is shown to be similar to Figure 9A The view.

[0049] [ Figure 10B ] Figure 10B It is shown in the disassembled state. Figure 10A The components of the half-shell.

[0050] [ Figure 11 ] Figure 11 This is a top view of the half-shell body of a dry vacuum pump according to a third exemplary embodiment.

[0051] [ Figure 12 ] Figure 12 yes Figure 11 AA section view of the half-shell.

[0052] [ Figure 13 ] Figure 13 yes Figure 11 A front view of the half-shell and half-partition.

[0053] In these figures, the same or similar elements have the same reference numerals.

[0054] For clarity, the accompanying drawings have been simplified. Only those elements necessary for understanding the invention are shown. Detailed Implementation

[0055] The following embodiments are examples. Although the specification refers to one or more embodiments, this does not necessarily mean that every mention refers to the same embodiment, or that these features apply only to a single embodiment. Simple features of different embodiments may also be combined or interchanged to provide other embodiments.

[0056] A "rough vacuum pump" is defined as a positive displacement vacuum pump constructed using two rotor shafts to draw in, transfer, and then discharge the gas to be pumped at atmospheric pressure. These rotor shafts are driven to rotate by the motor of the rough vacuum pump.

[0057] "Upstream" should be understood as an element placed before another element relative to the circulation direction of the gas to be pumped. Conversely, "downstream" should be understood as an element placed after another element relative to the circulation direction of the gas to be pumped.

[0058] "Axial direction" is defined as the longitudinal direction of the pump, along which the axis of the rotor shaft extends.

[0059] Figure 1 The dry vacuum pump 1 includes a stator 2 that forms at least two pump chambers consisting of pump stages 3a-3f—for example, two to ten pump stages (six in the illustrated example)—connected in series between the suction port 4 and the discharge port 5. The vacuum pump 1 is, for example, a rough vacuum pump.

[0060] Vacuum pump 1 also includes two rotor shafts 6 ( Figure 2 The rotor is configured to rotate synchronously in opposite directions within the pump chambers of pump stages 3a-3f, thereby driving the gas to be pumped between the suction port 4 and the discharge port 5. The rotor shaft 6 can be integral or made by assembling various additional components.

[0061] For example, the rotor has blades with the same profile, such as having two blades. Figure 2 The rotor may be a Roots-type rotor with one or more blades, or a claw-type rotor, or other similar rotors based on the principle of a positive displacement vacuum pump. The shaft carrying the rotor is driven by a motor (not shown), for example, located at the end of the vacuum pump 1 (e.g., on the side of the outlet 5).

[0062] Each pump stage 3a-3f of stator 2 is formed by a pump chamber that receives two conjugate rotors, and these pump chambers include corresponding inlets and outlets. During rotation, the gas drawn in from the inlet is trapped in the volume created by the rotors and stator 2, and then driven by the rotors to the next stage.

[0063] Successive pump stages 3a-3f are connected in series via corresponding interstage channels 9a-9e and 10a-10e, which connect the outlet of the previous pump stage 3a-3e to the inlet of the next pump stage 3b-3f. The vacuum pump 1 includes, for example, two transfer channels 9a-9e and 10a-10e, configured to connect the outlet of the pump chamber of the previous pump stage in parallel to the inlet of the next pump stage on both sides of the pump chamber. Figure 3 ).

[0064] The inlet of the first pump stage 3a is connected to the suction port 4 of the vacuum pump 1. The outlet 20 of the last pump stage 3f is connected to the discharge port 5. The axial dimensions of these rotors and pump chambers are, for example, equal, or they decrease with each pump stage, with the pump stage 3a located on the suction port 4 side receiving the rotor 6 with the largest axial dimension.

[0065] These vacuum pumps are described as "dry" because, during operation, the rotors rotate inside the stator 2, and there is no mechanical contact between them or between them and the stator 2, thus allowing the absence of oil in pump stages 3a-3f.

[0066] The stator 2 includes at least one first and at least one second complementary half-shell 7, 8. These half-shells are closed, for example, at their axial ends by a first end member and a second end member (not shown). The half-shells 7, 8 are joined to each other by a mating surface 11 to form the pump chambers of the at least two pump stages 3a-3f.

[0067] For example, the mating surface 11 is a flat mating surface that passes through, for example, the intermediate plane of a dry vacuum pump 1. The flat mating surface 11 includes, for example, the axis of the rotor shaft 6. The flat mating surface 11 can be strictly flat, or it can have, for example, a complementary raised surface or groove 12 for side rails for seals between the half-shells.

[0068] From the disassembled half-shell shown Figure 3 As can be better seen, the continuous pump chambers are separated from each other by partitions that are perpendicular to the longitudinal direction defined by the axial direction of the rotor shaft 6. Of course, orifices for the rotor shaft 6 to pass through are formed in the partitions and end members.

[0069] The pump chamber, partitions 13a-13e, 14a-14e, and interstage channels 9a-9e, 10a-10e are partially formed in the first half-shell 7 and partially formed in the second half-shell 8. Therefore, each half-shell 7 includes at least one half-partition 13a-13e, which engages with the half-partition 14a-14e of the other half-shell 8 to form a partition between two consecutive pump chambers. Furthermore, each half-shell 7 may include at least one half-channel 9a-9e, 10a-10e, which engages with the half-channel of the other half-shell 8 to form interstage channels 9a-9e, 10a-10e.

[0070] At least one of the half-partitions 13d, 13e, 14d, 14e of half-shell 8, which joins with the half-partitions 13d, 13e, 14d, 14e of the other half-shell 7 to separate two consecutive pump chambers, is assembled into a bracket 15 of said half-shell 8. At least one half-partition 13d, 13e, 14d, 14e is either detachably assembled into the bracket 15 or pressure-fitted into the bracket 15, as will be referred to later. Figures 11 to 13 What I saw.

[0071] "Removable" components should be understood as additional components that can be disassembled, replaced, or fixed without particular difficulty. In contrast, "non-removable" components refer to additional components that cannot be easily disassembled without damage. Assemblies achieved through pressure assembly are considered non-removable assemblies.

[0072] By utilizing at least one half-partition 13d, 13e, 14d, 14e assembled in the bracket 15 via detachable assembly or pressure assembly, the half-shells 7, 8 are easy to manufacture, especially compared to the bracket 15 which can be machined from the front without contour milling, thus reducing production costs. Furthermore, this architecture allows for the manufacture of pump chambers with narrow axial dimensions, without being limited by the size of production tools.

[0073] By utilizing at least one of the semi-partitions 13d, 13e, 14d, 14e, which are detachably assembled in the bracket 15 of the semi-shells 7 and 8, a portion of the semi-shells 7 and 8 can be easily removed for cleaning or replacement in case of blockage or damage. This reduces maintenance costs.

[0074] In addition, according to Figures 1 to 8 In the first exemplary embodiment shown, at least one half-partition 13d, 13e, 14d, 14e can be fixed to the bottom of the half-chamber, which is detachably fitted into the bracket 15 of the half-shells 7, 8.

[0075] The bottom of the semi-chamber is a hollow volume defined by the at least one removable semi-partition 13d, 13e, 14d, 14e and the lateral semi-wall 22. This hollow volume is axially closed by another removable semi-partition, or by an end piece, or by a non-removable semi-partition. This bottom of the semi-chamber is joined at the mating surface 11 to the bottom of the other semi-shell 7, 8 to form a pump chamber.

[0076] The bottom of the half-chamber—that is, the lateral half-wall 22 and the at least one half-partition 13d, 13e, 14d, 14e—is formed in an insert 23, which is detachably assembled into the support 15 of the half-shell. Figure 4 Since insert 23 is removable, it can be separated from bracket 15 to clean the bottom of the half-chamber.

[0077] Furthermore, since the interior of the interstage channel may also be difficult to access, which complicates its cleaning and manufacturing, it is conceivable that all or part of the interstage channel is made in a removable insert 23, especially in the insert located on the side of the outlet 5.

[0078] Therefore, according to an exemplary embodiment, at least a portion of the interstage semi-channels 9e and 10e is formed in the insert 23 of the half-shells 7 and 8. This portion of the interstage semi-channel opens on the side of the insert 23. Figure 7 ).

[0079] This portion of the interstage semi-channels 9e and 10e is therefore an open groove, which is axially closed by a removable semi-partition, an end piece, or a non-removable semi-partition to form the interstage semi-channel. This interstage semi-channel engages with the interstage semi-channels 9e, 10e, 9d, and 10d of the other half-shells 7 and 8 on the mating surface 11 to form interstage channels 9e, 10e, 9d, and 10d.

[0080] More specifically, these portions of the interstage semi-channels 9e, 10e, 9d, and 10d may be formed, for example, in a fixed semi-flange 16 next to the semi-partitions 13d, 13e, 14d, and 14e, which also allows the insert 23 to be secured to the bracket 15. For example, the interstage semi-channels 9e, 10e, 9d, and 10d are closed in the gas pumping direction by the fixed semi-flange 16 of the preceding pump chamber.

[0081] Two interstage semi-channels 9e, 10e, 9d, 10d are partially formed, for example, in the side of at least one insert 23, and the interstage semi-channels 9e, 10e, 9d, 10d are located on both sides of the semi-partitions 13d, 13e, 14d, 14e. For example, four interstage semi-channels form a ring around a pump chamber.

[0082] Another advantage of creating interstage channels in the removable insert 23 is that very fine channels can be made.

[0083] The removable insert 23, including the semi-partitions 13d, 13e, 14d, 14e and, where appropriate, the bottom of the semi-chamber and / or the interstage semi-channels, may be made of a material or have a coating that, for example, contains nickel or a coating such as nickel or NiP (nickel-phosphorus), which is more corrosion-resistant and / or wear-resistant and / or heat-resistant than the material or coating of the body of the semi-shells 7, 8, such as cast iron. Since more durable materials or coatings are generally also the most expensive, limiting their use to the insert 23 restricts their application to the parts of the semi-shell most vulnerable to external attack.

[0084] According to Figure 4 In one exemplary embodiment, which can be better seen in the image, at least one half-shell 7, 8 includes at least one removable fixing member 24, such as a screw, or a series of screws, here eight screws, for securing the removable half-partitions 13d, 13e, 14d, 14e to the bracket 15, and / or at least one half-shell 7, 8 includes at least one positioning member 25, such as a pin, for positioning the removable half-partitions in the bracket 15.

[0085] At least one insert 23 may have a fixed semi-flange 16, particularly forming part of an interstage semi-channel within it. For example, the at least one fixing member 24 and / or the at least one positioning member 25 are axially inserted into the fixed semi-flange 16 and the bracket 15 and / or another fixed flange 16.

[0086] More specifically, the removable insert 23 and the bracket 15 may each have a retaining semi-flange 16. The retaining semi-flange 16 has a flat and complementary form, wherein holes 17 may be formed for securing the member 24 and / or positioning the member 25. For example, through holes 17 are formed in the retaining semi-flanges 16 of the removable half-partitions 13d, 13e, 14d, 14e. The at least one retaining member 24 is inserted into at least two consecutive retaining semi-flanges 16 of the removable half-partitions 13e, 14e and another removable half-partition 13d, 14d or the bracket 15 to secure the removable half-partitions 13d, 13e, 14d, 14e to the bracket 15. The fixed semi-flange 16 of the removable semi-partitions 13d, 13e, 14d, 14e can therefore be clamped between the end member and another removable semi-partition 13d, 14d, or between the removable semi-partitions 13e, 14e and the fixed semi-flange 16 of the bracket 15.

[0087] According to another exemplary embodiment not shown, the at least one removable fixing member 24 is a semi-elastic washer or a metal clip axially interposed between the end member and another removable half partition 13d, 14d, 13e, 14e or between the removable half partition 13d, 14d, 13e, 14e and the bracket 15, so as to clamp the at least one removable half partition 13d, 14d, 13e, 14e onto the bracket 15.

[0088] The other half of the shell 7, 8, whose half-partitions 13d, 13e, 14d, 14e are joined to the at least one removable half-partition 13d, 13e, 14d, 14e, can also be detachably assembled. For example, there are two facing inserts 23.

[0089] For example, imagine at least one half-shell 7, 8 including at least two removable half-partitions 13d, 13e, which are joined together with two removable half-partitions 14d, 14e of another half-shell 8 to separate three consecutive pump chambers 3d, 3e, 3f.

[0090] For example, the half-partitions 13e and 14e of the half-shells 7 and 8 that separate the pump chambers of the last pump stage 3f and the penultimate pump stage 3e are removable. Figure 4 It is also conceivable that the semi-partitions 13d and 14d of the semi-shells 7 and 8 that separate the pump chambers of the penultimate pump stage 3e and the penultimate pump stage 3d are removable.

[0091] More specifically, it can be envisioned that the removable insert 23, which includes the facing half-partitions 13e, 14e and, where appropriate, the bottom of the half-chamber and / or the interstage half-channel and may have a more durable material or coating, is the insert for the last pump stage, or it may be the insert for the penultimate pump stage.

[0092] Preferably, the pump stages 3f and 3e located on the outlet 5 side of the vacuum pump 1 are at least partially removable, meaning that the pump stages located on the highest pressure side are at the greatest risk of corrosion and wear. Therefore, the half-partitions or inserts 23 can be easily replaced or cleaned. Furthermore, in the prior art half-shells, these last pump stages are the narrowest and therefore the most difficult to machine.

[0093] For example, they are the same inserts 23 used for the last two pump stages 3e and 3f, which further simplifies manufacturing.

[0094] Other semi-partitions 13a-13c and 14a-14c may be non-removable. Figure 5 and 6 ).

[0095] For example, it can be envisioned that at least one half-shell 7, 8 includes at least one half-partition 13d, 13e, 14d, 14e assembled by detachable assembly and at least one non-detachable half-partition 13a-13c, 14a-14c.

[0096] The half-partitions 13a-13c and 14a-14c that are joined together with the half-partitions 13a-13c and 14a-14c that are assembled by non-removable assembly can also be assembled by non-removable assembly.

[0097] The at least one non-removable semi-partition 13a-13c, 14a-14c is, for example, made in the body of the semi-shells 7, 8, or assembled in the support 15 of the semi-shells 7, 8 by pressure assembly.

[0098] Non-removable semi-partitions 13a-13c, 14a-14c are, for example, those semi-partitions interposed between the first pump stages 3a-3c, where the pressure is lowest and the risk of corrosion or wear is lowest. The non-removable semi-partitions 13a-13c, 14a-14c allow for the retention of advantages such as reduced assembly time and reduced use of fixing and positioning components in the semi-shell structure.

[0099] After the assembly of the at least one removable half-partition or the at least one insert 23, the half-shells 7 and 8 are secured together, for example, by screws. The vacuum pump 1 may also include at least one resilient seal disposed between the two half-shells 7 and 8. Alternatively, these half-shells may include a hardenable seal between the two half-shells 7 and 8.

[0100] In addition, although not shown in the figure, the vacuum pump 1 may also include at least one integral pump stage, which is installed in series upstream or downstream of at least one pump stage 3a-3f formed in at least the first and second half-shells 7, 8.

[0101] Furthermore, the stator 2 may include at least two pairs of complementary half-shells. For example, two half-shells 7 and 8 form two pump stages 3a and 3b, another two half-shells 7 and 8 form another two pump stages 3c and 3d, and another two half-shells 7 and 8 form another two pump stages 3e and 3f, with pump stages 3a-3f connected in series between the suction port 4 and the discharge port 5 of the vacuum pump 1.

[0102] Figure 9A , 9B Figures 10A and 10B illustrate another exemplary embodiment, in which only the semi-partitions 13d and 13e of the half-shells 7 and 8 are detachably fitted into the brackets 15 of the half-shells 7 and 8. In other words, in this example, the bottom of the half-chamber and the interstage semi-passage are not removable.

[0103] There are multiple configurations for implementing the fixing member 24 and the positioning member 25.

[0104] exist Figure 9A and 9B In the example, the at least one fixing member 24 and / or the at least one positioning member 25 are radially inserted into the bracket 15 through the removable half-partitions 13d, 13e.

[0105] For example, each removable half-partition 13d, 13e has at least two positioning members 25, such as two pins, arranged radially and non-parallel. Figure 9A In this case, a fixation member 24, which may or may not be added, may be installed, for example, in the same radially implanted manner.

[0106] Figure 9B Another exemplary embodiment is shown, wherein each removable half-partition 13d, 13e has at least two positioning members 25, such as a key and a pin, arranged radially and non-parallel. In this case, a fixing member 24, also radially inserted and parallel to the pin, may or may not be added. For example, the pin and fixing member 24 are inserted into the bottom of the chamber. The key is arranged on the edge of the half-chamber.

[0107] Figure 10A and 10B Another example is shown, in which at least two locating members 25 (e.g., two pins) and at least two fixing members 24 (e.g., three screws) are arranged axially. The pins and screws of the fixing members 24 are inserted in a parallel direction.

[0108] The variety of implementation options allows the manufacturing process to be adapted to the production tools used to make half-partitions and half-shells.

[0109] Figure 11 , 12 Figures 1 and 13 illustrate a third exemplary embodiment.

[0110] In this example, at least one half-partition 14 of the half-shells 7 and 8, which is joined to a half-partition of another half-shell 7 and 8 to separate two consecutive pump chambers, is pressure-fitted into a bracket 15.

[0111] For this purpose, for example, a transverse positioning groove 26 is formed in the support 15. The thickness of the at least one half-partition 14 is slightly greater than the width of the transverse positioning groove 26 of the half-shell 8 that houses it.

[0112] Pressure assembly can be performed below the press or by heating the half-shells 7 and 8 and / or cooling the at least one half-partition 14 to receive it in the transverse positioning groove 26. Pressure assembly can effectively secure the at least one half-partition 14 to the bracket 15, that is, in particular prevent vibration of the at least one half-partition 14 during operation of the vacuum pump 1.

[0113] Once the pressure assembly is complete, the mating surfaces 11 can be further processed, particularly by grinding each half-shell 7, 8, at the top of the body of the half-shell 7, 8, and at the top of the at least one half-partition 14, to ensure the mating complementarity of the half-shells 7, 8.

[0114] The semi-shells 7 and 8 are therefore easier to manufacture, which reduces production costs. Furthermore, this architecture allows for the creation of pump chambers with narrow axial dimensions, without being limited by the size of the production tools.

[0115] As in the first exemplary embodiment, the other half of the shell 7, 8, which is engaged with the at least one pressure-fitted half-partition 14, can also be pressure-fitted.

[0116] For example, it is conceivable that all the half-partitions 14 of the half-shells 7 and 8 are pressure-assembled. In this case, the main body of the half-shells 7 and 8 can be obtained by extrusion and then by machining the transverse positioning grooves 26.

[0117] Alternatively, it is conceivable that at least one of the half-partitions 14 of the half-shells 7 and 8 is removable or formed within the body of the half-shells 7 and 8. For example, the body of the half-shells 7 and 8 can be obtained by casting and then machining the transverse positioning grooves 26 and the mating surfaces 11.

[0118] For example, the half-partition 14 of the half-shells 7 and 8, which separates the pump chambers of the last pump stage 3f and the penultimate pump stage 3e, is pressure-assembled. These last pump stages are the narrowest and therefore the most difficult to machine.

[0119] Moreover, interstage channels may be difficult to form, so it is conceivable that they are formed, in whole or in part, in the half-partition of the pressure assembly located on the side of the outlet 5, especially in the thinnest half-partition.

[0120] Thus, for example, at least a portion of an interstage semi-channel is formed in the insert 23 of the half-shells 7, 8, and an opening is made on the side of the insert 23, which carries the half-partition 14 and is assembled in the bracket 15 by pressure fitting.

[0121] The at least one pressure-fitted half-partition 14 may also be made of a material or have a coating that, for example, contains nickel or a coating such as nickel or NiP (nickel-phosphorus), which is more corrosion-resistant and / or wear-resistant and / or heat-resistant than the material or coating of the body of the half-shells 7, 8, such as cast iron.

Claims

1. A dry vacuum pump (1), comprising: - Stator (2), the stator (2) comprising at least one first and at least one second complementary half-shell (7, 8), each half-shell (7, 8) comprising at least one half-partition (13a-13e), the half-partition (13a-13e) being joined together with the half-partition (14a-14e; 14) of the other half-shell (8) to form a partition between two consecutive pump chambers of pump stages (3a-3f), the pump stages (3a-3f) being installed in series between the suction port (4) and the discharge port (5) of the vacuum pump (1). - Two rotor shafts (6) configured to rotate synchronously in opposite directions within the pump chamber. Characterized by the fact that at least one half-partition (13d, 13e, 14d, 14e; 14) of the half-shell (7, 8) is assembled in the support (15) of the half-shell (7, 8) by a detachable assembly; and At least one half-partition (13d, 13e, 14d, 14e) is fixed to the bottom of the half-chamber, the bottom of the half-chamber being detachably fitted into the bracket (15) of the half-shell (7, 8), and the bottom of the half-chamber and the at least one half-partition (13d, 13e, 14d, 14e) are formed in a detachable insert (23) of the half-shell (7, 8). The vacuum pump (1) includes at least one interstage channel configured to connect the outlet (20) of a preceding pump stage (3a-3e) to the inlet (21) of a subsequent pump stage (3b-3f). Each half-shell (7, 8) includes at least one interstage half-channel, which engages with the interstage half-channel of another half-shell to form the interstage channel. At least a portion of the interstage half-channel is formed in an insert (23) of the half-shell (7, 8) and has an opening on the side of the insert (23). The insert (23) carries half-partitions (13d, 13e, 14d, 14e) and is assembled in the bracket (15) by a detachable assembly. The at least one interstage semi-channel is formed in a fixed semi-flange (16) on the side of the semi-partition (13d, 13e, 14d, 14e), and the fixed semi-flange (16) can also fix the insert (23) to the bracket (15).

2. The vacuum pump (1) according to claim 1, characterized in that, At least one half-shell (7, 8) includes: - At least one detachable fixing member (24) for securing the detachable half-partitions (13d, 13e, 14d, 14e) to the bracket (15), and / or - At least one positioning member (25) for positioning the removable half partitions (13d, 13e, 14d, 14e) in the bracket (15).

3. The vacuum pump (1) according to claim 2, characterized in that, The at least one fixing member (24) is a screw.

4. The vacuum pump (1) according to claim 2 or 3, characterized in that, The at least one positioning member (25) is a pin or a key.

5. The vacuum pump (1) according to claim 2, characterized in that, The half-shell (7, 8) includes at least one insert (23) that carries the at least one half-partition (13d, 13e, 14d, 14e), the insert (23) having a fixed half-flange (16), the at least one fixing member (24) and / or the at least one positioning member (25) being inserted into the fixed half-flange (16) and into the bracket (15) and / or another fixed half-flange (16).

6. The vacuum pump (1) according to claim 5, characterized in that, The at least one fixing member (24) and / or the at least one positioning member (25) are axially inserted into the fixing semi-flange (16) and the bracket (15) and / or another fixing semi-flange (16).

7. The vacuum pump (1) according to claim 5, characterized in that, The at least one fixing member (24) and / or the at least one positioning member (25) are radially inserted into the bracket (15) through the removable half-partitions (13d, 13e, 14d, 14e).

8. The vacuum pump (1) according to claim 1, characterized in that, The vacuum pump (1) includes two interstage semi-channels partially formed in the side of at least one insert (23), the interstage semi-channels being located on both sides of the semi-partitions (13d, 13e, 14d, 14e).

9. The vacuum pump (1) according to claim 1, characterized in that, At least one half-partition (14) is assembled in the bracket (15) by pressure fitting.

10. The vacuum pump (1) according to claim 9, characterized in that, The insert (23) of the pressure-bearing half-partition (14) is assembled in the bracket (15) by pressure assembly.

11. The vacuum pump (1) according to claim 1 or 2, characterized in that, The at least one half-partition (13d, 13e, 14d, 14e; 14) or at least one insert (23) carrying the at least one half-partition assembled by assembly is made of a material or has a coating that is more corrosion-resistant and / or wear-resistant than the material or coating of the body of the half-shell (7, 8).

12. The vacuum pump (1) according to claim 11, characterized in that, The material or coating of the at least one half-partition (13d, 13e, 14d, 14e; 14) or the at least one insert (23) carrying the at least one half-partition assembled by assembly is a nickel-containing material or coating, and the material or coating of the body of the half-shell (7, 8) is cast iron.

13. The vacuum pump (1) according to claim 1 or 2, characterized in that, The at least one half-partition (13d, 13e, 14d, 14e) assembled in the bracket (15) of the half-shell (7, 8) is joined together with at least one half-partition (13d, 13e, 14d, 14e) also assembled in the bracket (15) of the other half-shell (7, 8).

14. The vacuum pump (1) according to claim 1 or 2, characterized in that, At least one half-shell (7, 8) includes at least two half-partitions (13d, 13e) assembled together, which are joined together with two half-partitions (14d, 14e) assembled together from another half-shell (8) to separate three consecutive pump chambers (3d, 3e, 3f).

15. The vacuum pump (1) according to claim 1 or 2, characterized in that, The half-shell (7, 8) with its half-partitions (13e, 14e; 14) separating the pump chambers of the last pump stage (3f) and the penultimate pump stage (3e) is assembled by assembly.

16. The vacuum pump (1) according to claim 15, characterized in that, The semi-partitions (13d, 14d; 14) that separate the pump chambers of the penultimate pump stage (3e) and the penultimate pump stage (3d) of the half-shell (7, 8) are assembled by assembly.

17. The vacuum pump (1) according to claim 1 or 2, characterized in that, At least one half-shell (7, 8) includes at least one half-partition (13d, 13e, 14d, 14e) assembled by a detachable assembly, and includes at least one non-detachable half-partition (13a-13c, 14a-14c).

18. The vacuum pump (1) according to claim 17, characterized in that, The at least one non-removable half-partition (13a-13c, 14a-14c) is formed in the body of the half-shell (7, 8) or assembled in the bracket (15) by pressure assembly.

19. The vacuum pump (1) according to claim 17, characterized in that, The half-partitions (13a-13c, 14a-14c) that are joined to the non-removable half-partitions (13a-13c, 14a-14c) are also non-removable.

20. A method for manufacturing a dry vacuum pump (1) according to any one of the preceding claims, wherein, At least one half-partition (13d, 13e, 14d, 14e; 14) of the half-shell (7, 8) is assembled in the bracket (15) of the half-shell (7, 8) by means of detachable assembly, wherein the at least one half-partition (13d, 13e, 14d, 14e) is fixed to the bottom of the half-shell, and the bottom of the half-shell and the at least one half-partition (13d, 13e, 14d, 14e) are formed in the detachable insert (23) of the half-shell (7, 8).

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