TW202206702A - Dry type vaccum pump - Google Patents

Abstract

Dry type vacuum pump (1) including at least one thermal control device (10; 20) coupled to the stator (2), the at least one thermal control device (10; 20) including a contact surface (11) in contact with the stator (2) along the at least two pumping stages (3a-3f), the contact surface (11) being partially open with at least one opening (12) to heat or cool the stator (2) more at the level of the contact surface (11).

Description

dry vacuum pump

The present invention relates to dry vacuum pumps.

Dry vacuum pumps include a plurality of pumping stages in series, in which the gas to be pumped is circulated between the suction and discharge ports. Known vacuum pumps include those with rotating vanes (also known as "Roots" pumps with two or more vanes), those with claws (also known as "Claw" pumps), screw pumps type pump.

These vacuum pumps are called "dry" because they operate with the rotors turning in the stator without any mechanical contact between the rotors or with the stator, which makes it possible to use no oil in the pumping stage.

In operation, the compression of the gas results in a high degree of heating of the vacuum pump. This temperature rise has the potential to prevent the contamination or solidification of the contaminating gas species in the vacuum pump into a powder. However, for some applications, the temperature of the stator must be controlled so as not to exceed a predefined maximum value, beyond which the pumped gas species may form clusters and bind in the pump. It may also be necessary to cool the bearings of the vacuum pump to avoid failure. Certain parts of the vacuum pump therefore sometimes have to be heated and others may have to be cooled.

Furthermore, the temperature regulation needs of vacuum pumps may not be the same everywhere, especially for high and low pressure stages. In fact, the high pressure stage may be hotter than the low pressure stage due to the higher compression ratio.

Similarly, the need for temperature control varies in each pumping application, depending on the characteristics of the gas species being pumped.

Each pumping application may thus require specific temperature control depending on the construction of the vacuum pump, the characteristics and flow of the gas being pumped.

In modern vacuum pumps, the vacuum pump is generally cooled by controlled circulation of water in an aluminum block thermally contacting the stator. Use a single thermal block to configure along the final pumping stage, although in this case there may be only one temperature set point; or use two thermal regulation loops at the two ends of the vacuum pump: the first cooling loop on the low pressure stage side can therefore be appropriate The temperature on the low pressure side is controlled, and the second cooling circuit on the high pressure stage side can be controlled differently on the high pressure side. It is then possible to have different temperature set points on the low and high pressure sides. However, this architecture doubles the control cost because it requires the use of two temperature sensors and two regulating valves. Furthermore, the control of the temperature profile will lack correctness, because all the structure of the stator is based on these two measurement points for temperature control. This may not correspond to a particular temperature profile of a plurality of hot spots or a central hot spot included in the stator, such as a bell-shaped temperature profile, which is hotter in the center due to gas compression.

It is an object of the present invention to address at least one disadvantage of the prior art.

To this end, the present invention is for this purpose a dry vacuum pump comprising: a stator forming at least two pumping stages mounted in series between the suction orifice and the discharge orifice, The two shafts of the rotor, which are constructed in the compression chamber of the pumping stage to rotate in a synchronized manner in opposite directions, The dry vacuum pump is characterized in that the vacuum pump further includes at least one thermal control device coupled to the stator, the at least one thermal control device including a contact surface that contacts the stator along at least two pumping stages, the contact surface being defined by at least one opening. Partially open to further heat or cool the stator at the level of the contact surface.

A single thermal control device thus enables different thermal controls in the two zones of the stator, which can be adjusted at will to the thermal profile of the stator. In fact, it is extremely simple and relatively inexpensive to tailor the contact surface to the temperature profile required for a particular pumping application by simply modifying the shape and/or area of the opening. The stator may be overall temperature controlled using only a portion of the prior art thermal block. The variable geometry thermal control device is thus easily modifiable and can respond to the needs of different temperature profiles of the stator. It is thus possible to make relatively complex temperature control profiles, especially to homogenize the temperature of the stator at the level of one or more hot spots. For example, it is possible to configure the openings according to detailed temperature maps, which have been previously measured, for example, with thermal cameras or obtained with simulations.

The vacuum pump may further include one or more of the features described below separately and/or in combination.

At least one thermal control device may include a thermal block configured to heat or cool and a thermal interface plate disposed between the thermal block and the stator, the thermal interface plate carrying the contact surface, and at least one opening formed in the thermal interface plate. The implementation of this solution is simple as it is sufficient to modify the thermal interface plate to modify the thermal response of the stator. By adapting the thermal interface plate design of the thermal control device, it is possible and easy to modify the temperature distribution of the stator to suit the pumping application.

The thermal interface panel may be made of metal. The metal thermal interface plate can obtain better latent resistance.

Thermal interface panels may be fabricated as thermal pads. The thermal pad is flexible, easy to use and enables excellent thermal contact between the stator and the thermal block, including in the case of irregular surfaces. The thermal pads can actually remove the roughness, potentially avoiding the costs associated with getting a flat surface on the stator.

At least one thermal control device may include a thermal block configured to heat or cool, wherein blind pockets are formed at the level of the openings to form contact surfaces. This particular aspect is simply obtained by machining out the entire prior art parallelepiped thermal block, and using all its surfaces.

The area of the portion of the contact surface that contacts the final pumping stage in the gas circulation direction is, for example, larger than the area of the portion of the contact surface that contacts the first pumping stage.

For example, the area of the contact surface increases in the order of arrangement of the pumping stages in the gas circulation direction, the part of the contact surface that contacts the first pumping stage at the lower pressure has the smallest area.

The compression chamber of the first pumping stage, which has a lower pressure than the last pumping stage, is less hot because there is less compression of the gas. The risk of corrosion and condensation of solid species is lower because of this lower pressure. The first pumping stage thus requires less heating or cooling, in particular less cooling, than the last pumping stage. By cooling the last pumping stage more, it is possible to obtain a relatively uniform temperature along the pumping stage.

The contact surface comprises, for example, a plurality of openings, the density and/or area of which decreases along at least two pumping stages in the gas circulation direction.

The vacuum pump comprises, for example, at least two thermal control devices, the contact surfaces of which are arranged on individual sides of the stator.

The area of the contact surface of the thermal control device to the upper part of the stator where the compression chamber inlet is located may be smaller than the area of the contact surface of the thermal control device to the lower part of the stator where the compression chamber outlet is located. In fact, the pressure at the inlet of the compression chamber located in the upper part of the stator is lower than the pressure at the outlet of the compression chamber located in the lower part of the stator, and the upper part may therefore have to cool less. By cooling the lower part more than the upper part, a relatively uniform temperature is obtained in the upper and lower parts of the compression chamber.

The contact surface may include a plurality of openings with decreasing density and/or area from top to bottom.

The area of the central portion of the contact surface is, for example, larger than the area of the end portion of the contact surface.

The vacuum pump may include: at least one temperature sensor configured to measure the temperature of the stator; and a control unit configured to control the temperature of the stator by at least one thermal control device and at least one temperature sensor.

The axial dimensions of the rotor and the compression chamber are for example equal or decreasing in the order of arrangement of the pumping stages, the pumping stage on the suction port side receiving the rotor with the largest axial dimension.

The stator may include at least one first and one second half-shell, and the vacuum pump includes at least one first and at least one second thermal control device, one coupled to the first half-shell and the other coupled to the second half-shell.

The following specific forms are examples. Although the description refers to one or more specific aspects, it does not necessarily mean that each reference to the same specific aspect or feature applies only to one specific aspect. Individual features of different specific aspects may be combined equally or interchanged to provide other specific aspects.

"Upstream" means that one element is placed before another with respect to the direction of circulation of the gas to be pumped. Conversely, "downstream" means that one element is placed behind another with respect to the direction of circulation of the gas to be pumped.

The axial direction is defined as the longitudinal direction of the vacuum pump, where the axis of rotation of the rotor shaft extends.

The words "upper", "lower", "horizontal", "side", "top", and "bottom" refer to vacuum pumps placed on the ground And the definition, as shown in Figure 1.

The dry vacuum pump 1 of FIG. 1 comprises a stator 2 which forms between the suction orifice 4 and the discharge orifice 5 at least two pumping stages 3a to 3f installed in series, for example two to ten pumping stages, as shown in FIG. 1 . The example is six. This vacuum pump 1 is, for example, the main vacuum pump.

The vacuum pump 1 further comprises two shafts 6 of the rotor 7, which are constructed in the compression chambers of the pumping stages 3a-3f to rotate in a synchronized manner in opposite directions, to drive in the directions indicated by the arrows in Fig. 1 Gas to be pumped.

The rotor 7 comprises, for example, vanes with the same profile, for example a "Lu type" with two or more vanes, or a "claw type" or other similar positive displacement vacuum pump principle. The shaft 6 carrying the rotor 7 is driven by a motor 8 at one end of the vacuum pump 1, either on the side of the discharge orifice or on the side of the suction orifice 4 (Fig. 1).

Each pumping stage 3a-3f of the stator 2 is formed by a compression chamber that receives a biconjugate rotor 7, the compression chamber then comprising an individual inlet and an individual outlet. During rotation, the gas drawn in from the inlet is trapped in the volume created by the rotor 7 and the stator 2, and is then driven by the rotor 7 to the next stage.

Successive pumping stages 3a-3f are connected in series one after the other by means of individual intermediate stage channels which connect the outlet of the preceding pumping stage to the inlet of the succeeding pumping stage.

The inlet of the first pumping stage 3a communicates with the suction orifice 4 of the vacuum pump 1 . The outlet of the last pumping stage 3c communicates with the discharge orifice 5 . The axial dimensions of the rotor 7 and the compression chamber are for example equal or decrease in the order of arrangement of the pumping stages 3a-3f in the pumping direction of the gas, the pumping stage 3a on the side of the suction orifice 4 receives Rotor 7 with largest axial dimension.

These vacuum pumps 1 are called "dry" because the rotor 7 rotates in the stator 2 during operation without any mechanical contact between them or with the stator 2, which may not be used in the pumping stages 3a-3f Oil.

The vacuum pump 1 further includes at least one thermal control device 10 coupled to the stator 2 . At least one thermal control device 10 comprises a contact surface 11 which at least partially contacts the stator 2 along the at least two pumping stages 3a-3f.

The contact surface 11 is flat. It preferably has a generally inscribed rectangular shape with its long sides extending in the axial direction. This contact surface 11 is partially opened by at least one opening 12 to further heat or cool the stator 2 at the level of the contact surface 11 . A single thermal control device 10 can thus perform different thermal controls in the two zones of the stator 2 , which thermal control can be adapted at will to the thermal profile of the stator 2 . In fact, it is extremely simple and relatively low cost to tailor the contact surface 11 to the temperature profile required for a particular pumping application by simply modifying the shape and/or area of the opening 12 . The stator 2 may be overall temperature controlled using only a portion of the prior art thermal block. The variable geometry thermal control device 10 is thus easily modifiable and able to respond to different temperature profile requirements of the stator 2 . It is thus possible to make relatively complex temperature control profiles, in particular to homogenize the temperature of the stator 2 at the level of one or more hot spots. It is possible, for example, to configure the openings 12 according to a detailed temperature map, which for example has been measured in advance with a thermal camera or obtained with a simulation.

The vacuum pump 1 may further comprise: at least one temperature sensor 13 configured to measure the temperature of the stator 2; temperature. The control unit 14 includes a controller, microcontroller, memory and software capable of providing temperature control. This is for example a computer or industrial type programmable automatic controller. The temperature sensor 13 is arranged, for example, at the level of the last pumping stage 3f of the stator 2 in the pumping direction of the gas.

According to a first embodiment better seen in FIGS. 2 and 3 , at least one thermal control device 10 includes a parallelepiped thermal block 15 configured for heating or cooling and a thermal interface disposed between the thermal block 15 and the stator 2 Plate 16 , the thermal interface plate 16 carries the contact surface 11 . At least one opening 12 is disposed in the thermal interface panel 16 . The implementation of this solution is simple as it is sufficient to modify the thermal interface plate 16 to modify the thermal response of the stator 2 . By adapting the design of the thermal interface plate 16 of the thermal control device 10, it is thus possible and easy to modify the temperature distribution of the stator 2 to suit the pumping application.

The thermal interface panel 16 is made of a thermally conductive material, such as a metal such as aluminum or an alloy, for example; or it may be fabricated, for example, by cutting to form a thermal pad, which is generally used to transfer heat from electronic components to the hot tank. The thermal pad is flexible. It is easy to use and enables excellent thermal contact between the stator 2 and the thermal block 15, including in the case of irregular surfaces. The thermal pad actually makes it possible to remove the roughness, which can avoid the costs associated with obtaining a flat surface on the stator 2 . The metal thermal interface plate 16 can obtain better creep resistance.

The thickness of the thermal interface panel 16 is, for example, between 0.2 and 1.5 mm (including 0.2 and 1.5 mm), for example, 0.5 mm.

The thermal block 15 and the thermal interface plate 16 are fixed (eg, bolted) to the stator 2 . Note that the holes required to secure the thermal interface plate 16 are not openings 12 that function to reduce heating or cooling of the contact surface 11 .

FIG. 2 shows an example in which the thermal block 15 is a heater. To this end, it comprises, for example, a heating resistor cassette 17 embedded in a metal block, such as an aluminum block, the heating resistor cassette 17 being able to carry an electric current, the operation of which is controlled by the control unit 14 . In the case of the heating block 15, the metal thermal interface plate 16 is preferred.

FIG. 3 shows an example of the thermal block 15 being a cooling thermal block. To this end, the thermal block 15 comprises a metal block, for example an aluminum block, through which a hydraulic circuit 18 (for example a water circuit at room temperature) passes. For example, it is possible to control the cooling power by controlling the circulation of the liquid by opening/closing the regulating valve under the control of the control unit 14 . In the case of cooling the thermal block 15, the thermal interface panel 16 fabricated as a thermal pad is preferred.

As can be seen in Figure 1, the area of the part 11d of the contact surface 11 in contact with the last pumping stage 3f at the higher pressure in the gas circulation direction is for example larger than the part of the contact surface 11 in contact with the first pumping stage 3a at the lower pressure Area of 11a. The area of the contact surface 11 increases for example in the arrangement order of the pumping stages 3a-3f in the gas circulation direction, the portion 11a of the contact surface 11 contacting the lower pressure first pumping stage 3a has the smallest area. The compression chamber of the first pumping stage 3a, which has a lower pressure than the last pumping stage 3f, is cooler because there is less compression of the gas. The risk of corrosion and condensation of solid species is here lower because of this lower pressure. The first pumping stage 3a thus requires less heating or cooling, in particular less cooling, than the last pumping stage 3f. With more cooling on the last pressure stage side, it is possible to obtain a relatively uniform temperature along the pumping stages 3a-3f.

For this purpose, the contact surface 11 comprises, for example, a plurality of openings 12, the density and/or the area of which decreases in the gas circulation direction along the at least two pumping stages 3a-3f.

In the example of FIGS. 1 to 3 , the contact surface 11 has a plurality of (three) pairs of bisected openings 12 , which are separated from each other by a strip of the contact surface 11 . These openings 12 open, for example, to the long sides of the rectangle inscribed by the general shape of the contact surface 11 . The area of the openings 12 decreases along the pumping stages 3a to 3f in the gas circulation direction.

The vacuum pump 1 comprises, for example, at least two thermal control devices 10 , the individual contact surfaces 11 of which are arranged on individual sides of the stator 2 . Two thermal control devices 10 may be provided equally on each side, and/or thermal control devices 10 may be provided above and below the stator 2 , ie on all four sides of the stator 2 .

The area of the contact surface 11 of the thermal control device 10 contacting the upper part of the stator 2 where the compression chamber inlet is located is, for example, smaller than the area of the contact surface 11 of the thermal control device 10 contacting the lower part of the stator 2 where the compression chamber outlet is located (FIG. 1). In fact, the pressure at the inlet of the compression chamber located above the stator 2 is lower than the pressure at the outlet of the compression chamber located in the lower part of the stator 2, and the upper part may therefore have to be cooled less. By cooling the lower part more than the upper part, a relatively uniform temperature is obtained in the upper and lower parts of the compression chamber.

To this end, the contact surface 11 comprises, for example, a plurality of openings 12, the density and/or area of which decreases from top to bottom.

According to the particular embodiment seen in Figure 1, the stator 2 comprises complementary at least one first and at least one second half-shell 2a, 2b. The half-shells 2a, 2b are closed at their axial ends, for example by first and second end pieces, and are assembled to each other on the assembly surface 19 to form the compression chambers of at least two pumping stages 3a-3f. The assembly surface 19 is, for example, a flat assembly surface, which for example passes through the middle plane of the vacuum pump 1 . The flat assembly surface 19 contains, for example, the axis of the shaft 6 of the rotor 7 . This assembly surface 19 may be strictly flat, or may, for example, comprise complementary shapes in relief or grooves to seal the longitudinal parts between the half-shells 2a, 2b.

The vacuum pump 1 includes, for example, at least one first and at least one second thermal control device 10, one of which is coupled to the first half-shell 2a and the other is coupled to the second half-shell 2b (FIG. 1). For example, the vacuum pump 1 includes at least four thermal control devices 10, two first thermal control devices 10 are coupled to respective sides of the first half-shell 2a, and two second thermal control devices 10 are coupled to the second half-shell 2b the individual side.

The thermal control device(s) 10 are coupled to the first half-shell 2a (ie, the upper half-shell 2a) containing the inlets of the compression chambers of the pumping stages 3a-3f in area, for example, smaller than the thermal control device(s) 10 coupled The area of the contact surface 11 of the second half-shell 2b (ie the lower half-shell 2b) containing the outlet of the compression chamber of the pumping stages 3a-3f.

While FIGS. 1-3 illustrate similar specific aspects with respect to the design of thermal interface panel 16, any specific aspects are possible. In this regard, Figures 4A-4F show other specific aspects, which enable differential heating or cooling at the top and bottom of the stator 2 in particular in relation to the position of the compression chamber inlet/outlet, and which can be related to the series pumping stage 3a. The left and right sides of the stator 2 are heated or cooled in the continuous position of ~3f.

In the example of FIG. 4A, the opening 12 opens to the short side of the rectangle inscribed by the general shape of the contact surface 11, which limits the portion of the contact surface 11 that contacts the low-pressure first pumping stage 3a. This opening 12 extends along the pumping stages 3a-3f and gradually becomes smaller until the penultimate pumping stage. The opening 12 is substantially "V" shaped, for example. This architecture allows for progressive, relatively proportional heating or cooling increasing in the direction of gas circulation.

The example of FIG. 4B differs from the former in that the two openings 12 here open to the respective short sides of the rectangle inscribed by the general shape of the contact surface 11 . These openings 12 extend and gradually become smaller along the pumping stages 3a to 3f in the central direction of the stator 2 whose contact surface 11 is solid. The openings 12 are each substantially "V" shaped, for example. The area of the central portion of the contact surface 11 is larger than the area of the end portion of the contact surface 11 , and this configuration enables, in particular, a more uniform temperature of the stator 2 with a bell-shaped thermal profile and a central hot spot.

In the example of FIG. 4C , the opening 12 is substantially rectangular, and the long side thereof is parallel to the short side of the rectangle inscribed with the contact surface 11 of the thermal interface panel 16 . In this embodiment, the thermal interface panel 16 includes a frame without openings, which gives it good mechanical strength to facilitate its installation, especially in the case of the embodiment fabricated by cutting a flexible thermal pad.

In the example of FIG. 4D , the contact surface 11 includes two openings 12 , the respective areas of which increase from top to bottom. The contact surface 11 has a first opening 12 arranged at the level of the partial contact surface 11 (which contacts the upper part of the stator 2 ) and a second opening 12 arranged at the level of the partial contact surface 11 (which contacts the lower part of the stator 2 ). The opening 12 is substantially rectangular, and its long side is parallel to the contact surface 11 and thus the long side of the rectangle in which the thermal interface panel 16 is inscribed.

In the example of FIG. 4E, the contact surface 11 includes a plurality of openings 12, the density of which varies along the at least two pumping stages 3a-3f. More precisely, there are more openings 12 in the part of the contact surface 11 that contacts the first pumping stage 3a. These openings 12 have, for example, individual circles, for example, the same area, which is simply machined in the metal thermal interface plate 16 .

FIG. 4F shows another example where a special heat distribution can be obtained because of the variable dimensions of the openings 12 .

5 and 6 show a second mode specific aspect of the thermal control device 20 .

At least one thermal control device 20 differs from what was previously described in that it includes a thermal block 21 constructed to heat or cool and preferably inscribed in a parallelepiped shape in one piece with the thermal interface panel 16 . A blind cavity is formed at the level of the opening 12 of the thermal block 21 to form the contact surface 11 . The contact surface 11 and the at least one opening 12 thus extend within the thickness of the thermal block 21 by a distance, eg, between 0.2 and 1 mm inclusive, eg 0.3 mm. This particular aspect is simply obtained by machining out the entire prior art parallelepiped thermal block, and using all its surfaces.

FIG. 5 shows an example of the configuration of the thermal block 21 for heating. As in the first embodiment, the thermal block 21 for this purpose comprises, for example, a heating resistor cassette 17 through which an electric current can be passed, the operation of which is controlled by the control unit 14 .

FIG. 6 shows an example where the thermal block 21 is constructed for cooling. To this end, it comprises, for example, a metal block, such as an aluminum block, through which the hydraulic circuit 18 passes, for example, the water in the ambient temperature circuit. For example, the cooling power can be controlled by controlling the liquid circulation by the control unit 14 controlling the on/off regulating valve to control the liquid circulation. It is thus possible to use a single regulating valve to control two different temperatures at the level of the contact surface 11 and at the level of the opening 12 , depending on the design of the contact surface 11 along the stator 2 .

1: Dry vacuum pump 2: Stator 2a: first half shell 2b: second half shell 3a~3f: Pumping stage 4: Suction orifice 5: Discharge orifice 6: Axle 7: Rotor 8: Motor 10: Thermal control device 11: Contact surface 11a~11d: Parts 12: Opening 13: Temperature sensor 14: Control unit 15: Hot Block 16: Thermal Interface Panel 17: Heating resistor cassette 18: Hydraulic circuit 19: Assembly Surface 20: Thermal control device 21: Hot Block

Other objects, features and advantages of the present invention will appear from the following description of particular embodiments given with reference to the accompanying drawings.

[Fig. 1] A schematic diagram showing the elements of the vacuum pump.

[ FIG. 2 ] A first specific aspect of the thermal control device is shown.

[ Fig. 3 ] A modification example of the first specific aspect of the thermal control device is shown.

[ FIG. 4A ] A specific variation of the thermal interface panel of the thermal control device is shown.

[ FIG. 4B ] Another specific variation of the thermal interface panel of the thermal control device is shown.

[ FIG. 4C ] Another specific variation of the thermal interface panel of the thermal control device is shown.

[FIG. 4D] shows another specific variation of the thermal interface panel of the thermal control device.

[ FIG. 4E ] Another specific variation of the thermal interface panel of the thermal control device is shown.

[FIG. 4F] shows another specific variation of the thermal interface panel of the thermal control device.

[ Fig. 5 ] A second specific aspect of the thermal control device is shown.

[ Fig. 6 ] A modification example of the second specific aspect of the thermal control device is shown.

In the figures, the same elements are provided with the same reference signs. The diagrams are simplified for easier understanding.

1: Dry vacuum pump

2: Stator

2a: first half shell

2b: second half shell

3a~3f: Pumping stage

4: Suction orifice

5: Discharge orifice

6: Axle

7: Rotor

8: Motor

10: Thermal control device

11: Contact surface

11a, 11d: Parts

12: Opening

13: Temperature sensor

14: Control unit

19: Assembly Surface

Claims (15)

A dry vacuum pump (1), comprising: a stator (2) forming at least two pumping stages (3a-3f) installed in series between the suction orifice (4) and the discharge orifice (5), The two shafts (6) of the rotor (7), which are constructed in the compression chambers of the pumping stages (3a-3f) to rotate in a synchronized manner in opposite directions, The dry vacuum pump (1) is characterized in that the vacuum pump (1) further comprises at least one thermal control device (10, 20) coupled to the stator (2), the at least one thermal control device (10, 20) comprising a contact surface (11), which contacts the stator (2) along the at least two pumping stages (3a~3f), the contact surface (11) is partially opened by at least one opening (12) to be in contact with the contact surface (11) ) level more heats or cools the stator (2). The vacuum pump (1) according to claim 1, wherein the at least one thermal control device (10) comprises a thermal block (15) configured to heat or cool and a thermal block (15) arranged between the thermal block (15) and the stator (2) A thermal interface plate (16) carrying the contact surface (11), the at least one opening (12) being formed in the thermal interface plate (16). The vacuum pump (1) according to claim 2, wherein the thermal interface plate (16) is made of metal. The vacuum pump (1) according to claim 2, wherein the thermal interface plate (16) is manufactured as a thermal pad. The vacuum pump (1) according to claim 1, wherein the at least one thermal control device (20) comprises a thermal block (21) configured to heat or cool, wherein blind pockets are formed at the level of the opening (12) to form the contact surface (11). The vacuum pump (1) according to claim 1, wherein the area of the portion (11c) of the contact surface (11) in contact with the final pumping stage (3f) in the gas circulation direction is larger than that of the contact surface (11) in contact with the first pump The area of the part (11a) of the grade (3a). The vacuum pump (1) according to claim 1, wherein the area of the contact surface (11) increases in the order of arrangement of the pumping stages (3a-3f) in the gas circulation direction, the contact surface (11) contacting the lower The portion (11a) of this first pumping stage (3a) of pressure has the smallest area. The vacuum pump (1) according to claim 6 or 7, wherein the contact surface (11) comprises a plurality of openings (12), the density and/or area of which is along the at least two pumping stages (3a~ 3f) and decrease. Vacuum pump (1) according to any of claims 1 to 7, wherein it comprises at least two thermal control devices (10, 20), the contact surfaces (11) of which are arranged on individual sides of the stator (2). The vacuum pump (1) according to claim 9, wherein the area of the contact surface (11) of the thermal control device (10, 20) in contact with the upper part of the stator (2) where the compression chamber inlet is located is smaller than the thermal control device (10) , 20) The area of the contact surface (11) that contacts the lower part of the stator (2) where the outlet of the compression chamber is located. The vacuum pump (1) according to claim 10, wherein the contact surface (11) comprises a plurality of openings (12), the density and/or area of which decreases from top to bottom. The vacuum pump according to any one of claims 1 to 5, wherein the area of the central portion of the contact surface (11) is larger than the area of the end portion of the contact surface (11). The vacuum pump (1) according to any one of claims 1 to 7, wherein it comprises: at least one temperature sensor (13) configured to measure the temperature of the stator (2); and a control unit (14) configured to The temperature of the stator (2) is controlled by the at least one thermal control device (10, 20) and the at least one temperature sensor (13). The vacuum pump (1) according to any one of claims 1 to 7, wherein the axial dimensions of the rotor (7) and the compression chamber are equal or decrease in the order of arrangement of the pumping stages (3a-3f), The pumping stage (3a) on the side of the suction orifice (4) receives the rotor (7) of the largest axial dimension. The vacuum pump (1) according to any one of claims 1 to 7, wherein the stator (2) comprises at least a first and a second half-shell (2a, 2b), the vacuum pump (1) comprising at least a first and a second half-shell (2a, 2b) At least one second thermal control device (10, 20), one of which is coupled to the first half-shell (2a) and the other is coupled to the second half-shell (2b).

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