(19)
(11)EP 3 619 432 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
05.05.2021 Bulletin 2021/18

(21)Application number: 18717120.2

(22)Date of filing:  13.03.2018
(51)International Patent Classification (IPC): 
F04C 29/12(2006.01)
(86)International application number:
PCT/IB2018/051661
(87)International publication number:
WO 2018/203151 (08.11.2018 Gazette  2018/45)

(54)

TRANSMISSION AND COMPRESSOR OR VACUUM PUMP PROVIDED WITH SUCH A TRANSMISSION

GETRIEBE SOWIE MIT SOLCH EINEM GETRIEBE AUSGESTATTETER VERDICHTER ODER VAKUUMPUMPE

TRANSMISSION ET COMPRESSEUR OU POMPE À VIDE ÉQUIPÉ D'UNE TELLE TRANSMISSION


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 04.05.2017 US 201762501245 P
24.01.2018 BE 201805038

(43)Date of publication of application:
11.03.2020 Bulletin 2020/11

(73)Proprietor: Atlas Copco Airpower, Naamloze Vennootschap
2610 Wilrijk (BE)

(72)Inventors:
  • VAN HOVE, Linus
    2610 Wilrijk (BE)
  • DE MAN, Steven
    2610 Wilrijk (BE)

(74)Representative: Van Minnebruggen, Ewan Benito Agnes et al
Atlas Copco Airpower, N.V. Airtec Division P.O. Box 101 Boomsesteenweg 957
2610 Wilrijk
2610 Wilrijk (BE)


(56)References cited: : 
EP-A1- 0 812 988
EP-A2- 0 200 152
WO-A1-83/03641
EP-A1- 1 892 204
WO-A1-00/42322
CN-U- 205 606 795
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description


    [0001] The present invention relates to a compressor or vacuum pump provided with a transmission.

    [0002] It is known that a transmission between a drive shaft of a motor and the driven shaft of, for example, a rotor of a compressor element, is provided with a housing in which the gearwheels of the transmission are located.

    [0003] In order to ensure a proper operation, oil is injected in the housing of the transmission to serve as lubricant.

    [0004] As the driven shaft runs from the compressor element to the transmission, seals are provided between the compressor element and the transmission.

    [0005] However, there will always be some leakage flow, which means some air will end up in the housing of the transmission thus causing a pressure build-up in the transmission.

    [0006] It is important to get rid of such positive pressure as said seals should not be exposed to too big a pressure difference because this can affect their proper operation.

    [0007] If the pressure difference is too great it is possible that air will leak from the transmission to the compressor element. This air will also contain the injected lubricant.

    [0008] Such situation needs to be avoided at all times, as this lubricant will unintentionally end up in the compressor element and cause the compressed air generated by the compressor element, to be polluted in this case with the lubricant.

    [0009] Certainly, in the case of oil-free applications whereby pure compressed air is required, such situation is not tolerable.

    [0010] The positive pressure could be let off into the atmosphere. This means that air with the lubricant ends up in the atmosphere. Such situation is preferably to be avoided for oil-free applications, as this lubricant will end up on or near the machine, and in so doing may accidentally also end up in the machine.

    [0011] This is why the housing of the transmission is connected with an oil separator, to be able to purify the oil-air mixture in the transmission via the oil separator and to let it off into the atmosphere. The separated oil can be channelled back to an oil reservoir, to subsequently be injected back into the transmission.

    [0012] In the known transmissions, use is made of compressed gas to obtain extraction from the transmission to the oil separator via a venturi channel.

    [0013] Part of the compressed gas generated by the compressor is used for this which is branched off to said venturi channel. Consequently, the oil-air mixture will be extracted from the transmission, whereby the compressed gas and the oil-air mixture are blown through a filter. Naturally this implies a loss of efficiency of the machine.

    [0014] Moreover, the branch can be interrupted or detach, such that the venturi channel loses its effect, such that no extraction to the oil separator takes place.

    [0015] Alternatively, it is also possible to obtain extraction via an external (electrical) source with, for example, a ventilator.

    [0016] However, this solution also implies an extra consumption of electricity, and also an additional risk if the external source fails, for example, in case of a power failure or break in the cable.

    [0017] The WO0042322 discloses a screw compressor with a transmission housing that provides an aperture on the bottom for oil to flow out of the housing.

    [0018] The purpose of the present invention is to provide a solution for at least one of said and other disadvantages. To this end, the invention relates to a compressor provided with a compressor element with a driven shaft and a motor with a drive shaft to drive the compressor element, said compressor further being provided with a transmission between said drive shaft and said driven shaft , which transmission comprises a housing and at least a driven gearwheel that is mounted on the driven shaft and a drive gearwheel that is mounted on a drive shaft, whereby the housing comprises two separated chambers, i.e. a first chamber that is connected to the driven shaft and a second chamber which is separate from the first chamber, whereby the first chamber is connected via a channel with the second chamber, whereby around the drive gearwheel or driven gearwheel the second chamber is formed, whereby the form of the second chamber is such that when the gearwheel in question rotates, a gas flow is created around this gearwheel which causes a negative pressure in the channel by the venturi effect.

    [0019] Said gas flow around the gearwheel is also called "gearwind" and is an air flow or vortex that is generated by the rotating teeth of the gearwheel.

    [0020] "The first chamber is connected with the driven shaft", means that this chamber is located on the side of the driven shaft, such that said leak flows end up in this chamber.

    [0021] A first advantage is that, because a negative pressure is created in the channel, an extraction of gas and any lubricant will take place as it were from said first chamber through the channel to the second chamber.

    [0022] This provides the advantage that because of this the pressure in the first chamber can be kept low, at a slight positive or negative pressure, within the limits of the pressure difference over the seals between the compressor element and the transmission.

    [0023] In the second chamber, where the gas and the lubricant of the first chamber end up, there will be a pressure build-up.

    [0024] Another major advantage is that this system does not require any external power source, i.e. compressed air or electricity.

    [0025] This also means there is no risk of failure or defect by a shut-down of this external power source.

    [0026] Furthermore, it is an automatic self-regulating system: the faster the gearwheels rotate, the more leakage flow there will be from the compressor element to the transmission, and the extraction of the first chamber will be greater the faster the gearwheels rotate.

    [0027] This means that the level of extraction of the first chamber will automatically adapt itself to the situation.

    [0028] Preferably the gearwheels and the housing form a tight fit, to minimise the leak path between the first chamber and the second chamber as much as possible and to thus create a sufficiently big pressure difference between both chambers.

    [0029] Preferably, the distance in a radial direction between the wall of the second chamber and the gearwheel in question is also greater in the rotation direction of the gearwheel in question.

    [0030] This will help to guide the "gearwind" generated by the gearwheel to thus increase the negative pressure in said channel.

    [0031] In a practical embodiment the second chamber in the housing described above extends from 0° to 225° of the circumference of the gearwheel in question departing from the position of engagement of the gearwheels.

    [0032] The embodiment described above minimises the vortex losses, such that the power required for the pressure build-up in the second chamber is compensated, and the venturi effect in the channel is maximised to guarantee the negative pressure in the first chamber.

    [0033] The invention also relates to a vacuum pump provided with a vacuum pump element with a driven shaft and a motor with a drive shaft to drive the vacuum pump element, said vacuum pump further being provided with a transmission between said drive shaft and said driven shaft, whereby said transmission comprises a housing and at least a driven gearwheel that is mounted on the driven shaft and a drive gearwheel that is mounted on a drive shaft, and in that the housing comprises two separated chambers, i.e. a first chamber that is connected to the driven shaft and a second chamber which is separate from the first chamber, whereby the first chamber is connected via a channel with the second chamber, whereby around the drive gearwheel or driven gearwheel the second chamber is formed, whereby the form of the second chamber is such that when the gearwheel in question rotates a gas flow is created around this gearwheel which causes a negative pressure in the channel by the venturi effect.

    [0034] With the intention of better showing the characteristics of the invention, a few preferred embodiments of a compressor or vacuum pump according to the invention are described hereinafter by way of an example, without any limiting nature, with reference to the accompanying drawings, wherein:

    figure 1 schematically shows a compressor according to the invention;

    figure 2 shows the transmission of figure 1 in detail;

    figure 3 shows a view according to the arrow F3 in figure 2.



    [0035] The compressor 1 shown in figure 1 essentially comprises a compressor element 2, a motor 3 and a transmission 4 between the compressor element 2 and the motor 3.

    [0036] The compressor element 2 is in this case a screw compressor element 2, which comprises a compressor element housing 5 and two co-operating screw rotors 6a, 6b, more specifically a male screw rotor 6a and a female screw rotor 6b, the lobes 7 of which turn into each other co-operatively.

    [0037] Both rotors 6a, 6b are mounted with bearings by means of their shaft 8 in the compressor element housing 5.

    [0038] The shaft 8 of one of the rotors 6b is extended and forms the driven shaft 9.

    [0039] This driven shaft 9 reaches into the housing 10 of the transmission 4, and the driven gearwheel 11 is mounted at the end of it.

    [0040] In order to close off the compressor element 2 from the transmission 4, two seals 12a, 12b are mounted on the driven shaft 9: an oil seal 12a and an air seal 12b.

    [0041] The motor 3 has a drive shaft 13 that reaches into the housing 10 of the transmission 4 and on which a drive gearwheel 14 is mounted that engages on said driven gearwheel 11.

    [0042] The transmission 4 comprises the aforementioned housing 10 with said gearwheels 11 and 14 therein.

    [0043] Of course, it is not excluded that in the housing 10 additional gearwheels are mounted between the driven gearwheel 11 and the drive gearwheel 14.

    [0044] Nor does this exclude that the motor 3 is located in the housing 10 of the transmission 4.

    [0045] A filter element 16 is connected to the housing 10 of the transmission 4, to be able to filter oil out of the oil-air mixture that is in the housing 10 of the transmission 4.

    [0046] In this case, but not necessarily, the housing 10 of the transmission 4 is connected to an oil reservoir 15 to collect the injected oil and this oil reservoir 15 is provided with a filter element 16.

    [0047] Furthermore, the compressor 1 in the shown example is also provided with an oil circuit 17, which can return the oil collected in the oil reservoir 15 with an oil pump 18, i.e. the oil that flows back out of the housing 10 and the oil separated by the filter element 16, back to the transmission 4 and/or the motor 3. Additionally, the oil circuit 17 is also provided with an oil filter 19 to be able to remove impurities from the oil.

    [0048] According to the invention the housing 10 of the transmission 4 comprises two chambers 20 and 22. A first chamber 20 which is connected to the driven shaft 9 and a second chamber 22 which is separate from the first chamber 20. This is shown in figure 2.

    [0049] As one can tell from figure 2, the driven shaft 9 extends into the first chamber 20.

    [0050] The second chamber 22 is provided around the drive gearwheel 14. The first chamber 20 is connected to this second chamber 22 via the channel 21.

    [0051] The form of the second chamber 22 is shown clearly in figure 3.

    [0052] In this case, the second chamber 22 is integrated in the wall 23 of the housing 10 of the transmission 4.

    [0053] However, it is also possible that the transmission 4 is provided with a shield that is mounted next to, around or against the gearwheel 14 and that is provided with a form similar to the second chamber 22. Such shield can be mounted in the housing 10. This provides the advantage that nothing needs to be changed to a possible existing housing 10.

    [0054] The second chamber 22 is such that the "gearwind" that is created by rotation of the drive gearwheel 14 is led along the channel 21 such that a negative pressure is caused in the channel 21 because of the venturi effect.

    [0055] As can be seen in figure 3, the second chamber 22 gets bigger in the rotation direction of the drive gearwheel 14, as was indicated with arrow P. Said channel 21 also connects to the end of the second chamber 22 as seen in the rotation direction P of the drive gearwheel 14, i.e. to its biggest end.

    [0056] Both characteristics will ensure that said effect will be as optimal as possible.

    [0057] The second chamber 22 extends from 0° to approximately 225° of the circumference of the drive gearwheel 14 in the rotation direction of arrow P, starting from the engagement of the gearwheels.

    [0058] Preferably, the rest of the circumference of the drive gearwheel 14 forms a tight fit.

    [0059] This will ensure that the vortex losses are reduced to a minimum.

    [0060] As can be seen in figure 1, the second chamber 22 is connected to the filter element 16 that is connected to the transmission 4. This filter element 16, for example, can be a venting filter or a liquid separator that is provided with a filter.

    [0061] Because the oil separation in the filter element 16 is always linked with a certain drop in pressure the result will be a positive pressure in the second chamber 22. This means extra vortex losses in the second chamber 22.

    [0062] According to the form of the second chamber 22, as shown in figure 3, the reduction of the vortex losses by the tight fit of the drive gearwheel 14 and the extra vortex losses in the second chamber 22 due to pressure build-up over the filter element 16 will cancel each other out which means no extra power of the motor 3 is necessary.

    [0063] The operation of the compressor 1 is very simple and as follows.

    [0064] During the operation of the compressor 1 the motor 3 will power the drive gearwheel 14, whereby the movement via the driven gearwheel 11 is transferred to the driven shaft 9 of the compressor element 2.

    [0065] Oil will be injected in the transmission 4 and possibly also the motor 3 for the cooling and/or lubrication of the gearwheels 11, 14, bearings and other parts.

    [0066] The operation of the compressor 1 will result in a certain pressure build-up in the transmission 4, as the air seal 12b on the driven shaft 9 will allow a certain leakage flow in the direction of the compressor element 2 toward the transmission 4.

    [0067] Consequently, in the housing 10 of the transmission 4 there will be an oil-air mixture at an increased pressure.

    [0068] The rotation of the drive gearwheel 14 will create a socalled "gearwind" in the chamber 22 whereby an air flow or vortex is generated by the rotating teeth of the drive gearwheel 14.

    [0069] By channelling this air flow along the channel 21 the venturi effect will cause a negative pressure in the channel 21.

    [0070] As a result of this negative pressure, the first chamber 20 will be sucked out as it were and the oil-air mixture in this chamber will end up in the second chamber 22 via the channel 21.

    [0071] This causes a pressure difference between the first chamber 20 and the second chamber 22, whereby the pressure in the first chamber 20 will be lower than the pressure in the second chamber 22.

    [0072] The lower pressure in the first chamber 20 prevents the seals 12a, 12b on the driven shaft 9 from being exposed to too big a pressure difference, such that it is avoided that the oil-air mixture can end up in the compressor element 2.

    [0073] The oil-air mixture ends up in the second chamber 22, where a pressure build-up will take place due to the drop in pressure over the filter element 16 after which the purified, oil-free air can be channelled out.

    [0074] The oil separated in the filter element 16 can then be injected back into the transmission 4 and/or the motor 3 via the oil circuit 17.

    [0075] Although in the shown example the second chamber 22 is provided around the drive gearwheel 14, it is not excluded that this chamber 22 is provided around the driven gearwheel 11 or another gearwheel, if present.

    [0076] However, preferably this chamber 22 extends along the gearwheel 11, 14 or another gearwheel, if present, with the greatest diameter and/or the greatest peripheral speed.

    [0077] As is visible in figure 3, the drive gearwheel 14 in this case is greater than the driven gearwheel 11 and the second chamber 22 is therefore also provided around the drive gearwheel 14.

    [0078] The bigger gearwheel 14 will, after all, be able to create a greater gas flow, such that the negative pressure in the channel 21 is greater and a better extraction of the first chamber 20 is obtained.

    [0079] According to the invention is it not necessary that it concerns a compressor 1 that is provided with a transmission 4 according to the invention. The machine could also be a vacuum pump.

    [0080] The present invention is by no means limited to the embodiments described as an example and shown in the drawings, but a compressor or vacuum pump according to the invention, can be realised in all kinds of forms and dimensions, without departing from the scope of the invention.


    Claims

    1. Compressor provided with a compressor element (2) with a driven shaft (3) and a motor(3) with a drive shaft (13) to drive the compressor element (2), said compressor (1) further being provided with a transmission (4) between said drive shaft (13) and said driven shaft (9), which transmission (4) comprises a housing (10) and at least a driven gearwheel (11) that is mounted on the driven shaft (9) and a drive gearwheel (14) that is mounted on a drive shaft (13), characterised in that the housing (10) comprises two separated chambers (20, 22), i.e. a first chamber (20) that is connected to the driven shaft (9) and a second chamber (22) which is separate from the first chamber (20), whereby the first chamber (20) is connected via a channel (21) with the second chamber (22), whereby around the drive gearwheel (14) or driven gearwheel (11) the second chamber (22) is formed, whereby the form of the second chamber (22) is such that the second chamber (22) gets bigger in the rotation direction (P) of the gearwheel (11, 14) around which the second chamber (22) is formed and whereby the channel (21) connects to the end of the second chamber (22) as seen in the rotation direction (P) of gearwheel (11, 14) around which the second chamber (22) is formed, all such that when the gearwheel (11, 14) around which the second chamber (22) is formed rotates a gas flow is created around this gearwheel (11, 14) which causes a negative pressure in the channel (21) by the venturi effect.
     
    2. Compressoraccording to claim 1, characterised in that the second chamber (22) is integrated in the wall (23) of the housing (10).
     
    3. Compressor according to claim 1 or 2, characterised in that the transmission (4) is provided with a shield that is mounted next to or against the gearwheel (11, 14) and is provided with a cut-away to form said second chamber (22).
     
    4. Compressor according to any one of the previous claims, characterised in that the second chamber (22) extends along the gearwheel (11, 14) with the greatest diameter and/or the greatest peripheral speed.
     
    5. Compressor according to any one of the previous claims, characterised in that the second chamber (22) extends from 0° to 225° of the circumference of the gearwheel in question (11, 14) starting from the position of engagement of the gearwheels (11, 14).
     
    6. Compressor according to any one of the previous claims, characterised in that the second chamber (22) extends over 25% to 75%, preferably even over 45% to 55% and even more preferably 50% of the circumference of the gearwheel in question (11, 14).
     
    7. Compressor according to any one of the previous claims, characterised in that the distance in a radial direction between the wall of the second chamber (22) and the gearwheel in question (11, 14) gets bigger in the rotation direction (P) of the gearwheel in question (11, 14).
     
    8. Compressor according to any one of the previous claims, characterised in that said channel (21) connects to the end of the second chamber (22), as seen in the rotation direction (P) of the gearwheel in question (11, 14).
     
    9. Compressor according to any one of the previous claims, characterised in that said second chamber (22) is in connection with a filter element (16) or the like connected to the transmission (4).
     
    10. Vacuum pump provided with a vacuum pump element with a driven shaft and a motor (3) with a drive shaft to drive the vacuum pump element, said vacuum pump further being provided with a transmission (4) between said drive shaft (13) and said driven shaft (9), characterized in that said transmission (4) comprises a housing (10) and at least a driven gearwheel (11) that is mounted on the driven shaft (9) and a drive gearwheel (14) that is mounted on a drive shaft (13), and in that the housing (10) comprises two separated chambers (20, 22), i.e. a first chamber (20) that is connected to the driven shaft (9) and a second chamber (22) which is separate from the first chamber (20), whereby the first chamber (20) is connected via a channel (21) with the second chamber (22), whereby around the drive gearwheel (14) or driven gearwheel (11) the second chamber (22) is formed, whereby the form of the second chamber (22) is such that the second chamber (22) gets bigger in the rotation direction (P) of the gearwheel (11, 14) around which the second chamber (22) is formed and whereby the channel (21) connects to the end of the second chamber (22) as seen in the rotation direction (P) of gearwheel (11, 14) around which the second chamber (22) is formed, all such that when the gearwheel (11, 14) around which the second chamber (22) is formed rotates a gas flow is created around this gearwheel (11, 14) which causes a negative pressure in the channel (21) by the venturi effect.
     


    Ansprüche

    1. Verdichter, der mit einem Verdichterelement (2) mit einer Abtriebswelle (3) und einem Motor (3) mit einer Antriebswelle (13) zum Antreiben des Verdichterelements (2) versehen ist, wobei der Verdichter (1) ferner mit einem Getriebe (4) zwischen der Antriebswelle (13) und der Abtriebswelle (9) versehen ist, wobei das Getriebe (4) ein Gehäuse (10) und mindestens ein auf der Abtriebswelle (9) gelagertes Abtriebszahnrad (11) und ein auf einer Antriebswelle (13) gelagertes Antriebszahnrad (14) umfasst, dadurch gekennzeichnet, dass das Gehäuse (10) zwei getrennte Kammern (20, 22) umfasst, nämlich eine erste Kammer (20), die mit der Abtriebswelle (9) verbunden ist, und eine zweite Kammer (22), die von der ersten Kammer (20) getrennt ist, wobei die erste Kammer (20) über einen Kanal (21) mit der zweiten Kammer (22) verbunden ist, wobei um das Antriebszahnrad (14) oder Abtriebszahnrad (11) herum die zweite Kammer (22) ausgebildet ist, wobei die Form der zweiten Kammer (22) derart ist, dass die zweite Kammer (22) in Drehrichtung (P) des Zahnrades (11, 14), um das die zweite Kammer (22) ausgebildet ist, größer wird, und wobei der Kanal (21) in Drehrichtung (P) des Zahnrades (11, 14) gesehen, um das die zweite Kammer (22) ausgebildet ist, an das Ende der zweiten Kammer (22) anschließt, alles derart, dass bei Rotation des Zahnrades (11, 14), um das die zweite Kammer (22) ausgebildet ist, eine Gasströmung um dieses Zahnrad (11, 14) erzeugt wird, die durch den Venturi-Effekt einen Unterdruck im Kanal (21) bewirkt.
     
    2. Verdichtemach Anspruch 1, dadurch gekennzeichnet, dass die zweite Kammer (22) in die Wand (23) des Gehäuses (10) integriert ist.
     
    3. Verdichter nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass das Getriebe (4) mit einer Abschirmung versehen ist, die neben oder gegen das Zahnrad (11, 14) montiert ist und mit einer Aussparung versehen ist, um die zweite Kammer (22) zu bilden.
     
    4. Verdichter nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass sich die zweite Kammer (22) entlang des Zahnrades (11, 14) mit dem größten Durchmesser und/oder der größten Umfangsgeschwindigkeit erstreckt.
     
    5. Verdichter nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass sich die zweite Kammer (22) ausgehend von der Eingriffsposition der Zahnräder (11, 14) von 0 ° bis 225 ° des Umfangs des betreffenden Zahnrads (11, 14) erstreckt.
     
    6. Verdichter nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass sich die zweite Kammer (22) über 25 % bis 75 %, vorzugsweise sogar über 45 % bis 55 % und noch bevorzugter über 50 % des Umfangs des betreffenden Zahnrads (11, 14) erstreckt.
     
    7. Verdichter nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass der Abstand in radialer Richtung zwischen der Wand der zweiten Kammer (22) und dem betreffenden Zahnrad (11, 14) in Drehrichtung (P) des betreffenden Zahnrades (11, 14) größer wird.
     
    8. Verdichter nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass der Kanal (21) an das Ende der zweiten Kammer (22) anschließt, gesehen in der Drehrichtung (P) des betreffenden Zahnrads (11, 14).
     
    9. Verdichter nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, dass die zweite Kammer (22) mit einem Filterelement (16) oder dergleichen in Verbindung steht, das mit dem Getriebe (4) verbunden ist.
     
    10. Vakuumpumpe, die mit einem Vakuumpumpenelement mit einer Abtriebswelle und einem Motor (3) mit einer Antriebswelle zum Antreiben des Vakuumpumpenelements versehen ist, wobei die Vakuumpumpe ferner mit einem Getriebe (4) zwischen der Antriebswelle (13) und der Abtriebswelle (9) versehen ist, dadurch gekennzeichnet, dass das Getriebe (4) ein Gehäuse (10) und mindestens ein Abtriebszahnrad (11), das auf der Abtriebswelle (9) montiert ist, und ein Antriebszahnrad (14), das auf einer Antriebswelle (13) montiert ist, umfasst, und dass das Gehäuse (10) zwei getrennte Kammern (20, 22) umfasst, nämlich eine erste Kammer (20), die mit der Abtriebswelle (9) verbunden ist, und eine zweite Kammer (22), die von der ersten Kammer (20) getrennt ist, wobei die erste Kammer (20) über einen Kanal (21) mit der zweiten Kammer (22) verbunden ist, wobei um das Antriebszahnrad (14) oder Abtriebszahnrad (11) herum die zweite Kammer (22) ausgebildet ist, wobei die Form der zweiten Kammer (22) derart ist, dass die zweite Kammer (22) in Drehrichtung (P) des Zahnrades (11, 14), um das die zweite Kammer (22) ausgebildet ist, größer wird, und wobei der Kanal (21) in Drehrichtung (P) des Zahnrades (11, 14) gesehen, um das die zweite Kammer (22) ausgebildet ist, an das Ende der zweiten Kammer (22) anschließt, alles derart, dass bei Rotation des Zahnrades (11, 14), um das die zweite Kammer (22) ausgebildet ist, eine Gasströmung um dieses Zahnrad (11, 14) erzeugt wird, die durch den Venturi-Effekt einen Unterdruck im Kanal (21) bewirkt.
     


    Revendications

    1. Compresseur pourvu d'un élément compresseur (2) avec un arbre entraîné (3) et un moteur (3) avec un arbre d'entraînement (13) pour entraîner l'élément compresseur (2), ledit compresseur (1) étant en outre pourvu d'une transmission (4) entre ledit arbre d'entraînement (13) et ledit arbre entraîné (9), laquelle transmission (4) comprend un logement (10) et au moins une roue d'engrenage entraînée (11) qui est montée sur l'arbre entraîné (9) et une roue d'engrenage d'entraînement (14) qui est montée sur un arbre d'entraînement (13), caractérisé en ce que le logement (10) comprend deux chambres séparées (20, 22), c'est-à-dire une première chambre (20) qui est reliée à l'arbre entraîné (9) et une deuxième chambre (22) qui est séparée de la première chambre (20), moyennant quoi la première chambre (20) est reliée par l'intermédiaire d'un canal (21) à la deuxième chambre (22), moyennant quoi autour de la roue d'engrenage d'entraînement (14) ou de la roue d'engrenage entraînée (11) la deuxième chambre (22) est formée, moyennant quoi la forme de la deuxième chambre (22) est telle que la deuxième chambre (22) devient plus grande dans la direction de rotation (P) de la roue d'engrenage (11, 14) autour de laquelle la deuxième chambre (22) est formée et moyennant quoi le canal (21) se relie à l'extrémité de la deuxième chambre (22) comme observé dans la direction de rotation (P) de la roue d'engrenage (11, 14) autour de laquelle la deuxième chambre (22) est formée, tout cela de telle sorte que lorsque la roue d'engrenage (11, 14) autour de laquelle la deuxième chambre (22) est formée tourne un flux de gaz est créé autour de cette roue d'engrenage (11, 14) lequel provoque une pression négative dans le canal (21) par l'effet venturi.
     
    2. Compresseurselon la revendication 1, caractérisé en ce que la deuxième chambre (22) est intégrée dans la paroi (23) du logement (10).
     
    3. Compresseur selon la revendication 1 ou 2, caractérisé en ce que la transmission (4) est pourvue d'un bouclier qui est monté à côté de ou contre la roue d'engrenage (11, 14) et est pourvue d'une découpe pour former ladite deuxième chambre (22).
     
    4. Compresseur selon l'une quelconque des revendications précédentes, caractérisé en ce que la deuxième chambre (22) s'étend le long de la roue d'engrenage (11, 14) avec le plus grand diamètre et/ou la plus grande vitesse périphérique.
     
    5. Compresseur selon l'une quelconque des revendications précédentes, caractérisé en ce que la deuxième chambre (22) s'étend de 0° à 225° de la circonférence de la roue d'engrenage en question (11, 14) en partant de la position d'engrènement des roues d'engrenage (11, 14).
     
    6. Compresseur selon l'une quelconque des revendications précédentes, caractérisé en ce que la deuxième chambre (22) s'étend sur 25 % à 75 %, de préférence même sur 45 % à 55 % et encore plus préférablement 50 % de la circonférence de la roue d'engrenage en question (11, 14).
     
    7. Compresseur selon l'une quelconque des revendications précédentes, caractérisé en ce que la distance dans une direction radiale entre la paroi de la deuxième chambre (22) et la roue d'engrenage en question (11, 14) devient plus grande dans la direction de rotation (P) de la roue d'engrenage en question (11, 14).
     
    8. Compresseur selon l'une quelconque des revendications précédentes, caractérisé en ce que ledit canal (21) se relie à l'extrémité de la deuxième chambre (22), comme observé dans la direction de rotation (P) de la roue d'engrenage en question (11, 14).
     
    9. Compresseur selon l'une quelconque des revendications précédentes, caractérisé en ce que ladite deuxième chambre (22) est en liaison avec un élément filtrant (16) ou similaire relié à la transmission (4).
     
    10. Pompe à vide pourvue d'un élément de pompe à vide avec un arbre entraîné et un moteur (3) avec un arbre d'entraînement pour entraîner l'élément de pompe à vide, ladite pompe à vide étant en outre pourvue d'une transmission (4) entre ledit arbre d'entraînement (13) et ledit arbre entraîné (9), caractérisée en ce que ladite transmission (4) comprend un logement (10) et au moins une roue d'engrenage entraînée (11) qui est montée sur l'arbre entraîné (9) et une roue d'engrenage d'entraînement (14) qui est montée sur un arbre d'entraînement (13), et en ce que le logement (10) comprend deux chambres séparées (20, 22), c'est-à-dire une première chambre (20) qui est reliée à l'arbre entraîné (9) et une deuxième chambre (22) qui est séparée de la première chambre (20), moyennant quoi la première chambre (20) est reliée par l'intermédiaire d'un canal (21) à la deuxième chambre (22), moyennant quoi autour de la roue d'engrenage d'entraînement (14) ou de la roue d'engrenage entraînée (11) la deuxième chambre (22) est formée, moyennant quoi la forme de la deuxième chambre (22) est telle que la deuxième chambre (22) devient plus grande dans la direction de rotation (P) de la roue d'engrenage (11, 14) autour de laquelle la deuxième chambre (22) est formée et moyennant quoi le canal (21) se relie à l'extrémité de la deuxième chambre (22) comme observé dans la direction de rotation (P) de la roue d'engrenage (11, 14) autour de laquelle la deuxième chambre (22) est formée, tout cela de telle sorte que lorsque la roue d'engrenage (11, 14) autour de laquelle la deuxième chambre (22) est formée tourne un flux de gaz est créé autour de cette roue d'engrenage (11, 14) lequel provoque une pression négative dans le canal (21) par l'effet venturi.
     




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    Cited references

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    Patent documents cited in the description