The present invention relates to a compressor de ice «

More specifically, the invention concerns & compressor device for compressing gas that c m is s a com ress eleme t ¾?ith a housing with an inlet and an outlet, whereby least one rotor is affixed in the housing that is provided wit a drive, whereby the compressor device is provided with an oil circuit for injecting oil into the hocsi g,

This rotor can be a helical rotor for example, in which case it is then a screw compressor elem n or for example an impeller or compressor wheel when it concerns a centrifugal, compressor element.

It is known that for the cooling and/or lubrication of tne compressor element use is made of oil that is injected into the housing of the compressor element.

This oil is guided around b means of an oil circuit through the compressor device.

To be able to inject the oil, the oil circuit is provided with an oil ian .

This oil pump is driven by means of the aforementioned drive that drives the rotor. hen the compressor de ice is bitched f, thereby the speed of the mo r d cre ses, the oil pursp will al he swi ched off so that no oil is injected _* Howeve when swi c ing off the compressor device it is important that sufficient oil is still injected for some time ,

Also when, starting «p the compressor device it is important that before the rotor cosses into operation, the oil can already circulate to lubricate the co ressor eleme .

In order to provide an oil supply in. these situations? in kn n installations an additional auxiliary u p with a separate drive is provided,

This auxiliary m villi come into operation wh n switching off and before starting up the drive of the rotor in order to pro ide the necessary oil injection,

Such, kno n installations also present the disadvantage that an additional auxiliary pum and auxiliary motor must be provided, whereby separate inlet and outlet pipes have to be provided,

Another disadvantage is that non-return valves must be provided in order to counteract a baekflow of oil when one of the pumps is switched off. ¾n additional disadvan ge is hat when tarting up, an overpressure can occur in the oil circuit. Indeed, at the m men that the drive c rner into operation, the p m wiiI also come into operation and the auxiliary pump must ho switched off. ¾s a result too great a quantity of oil will be uia ed around and injected,

Mo eo e , the changeover between the pmp and the auxiliary mp will cause a chance in the oil supply.

The ur ose of the present invention is to provide a solution to at least one of the aforementioned and other dis dv tages .

The object ox the present invention is a compressor device for compressing gaa that comprises a compressor element with a housing with an inle and an outlet, thereby at least one rotor is affixed in the housing that is provided with a drive,- whereby the compressor device is provided with an oil circuit for injecting oil into the housing, thereby the oil circuit only comprises one pump for driving the oil around in the oil circuit, whereby this nm is coupled to a first shaft via a first Ciaengageable coupling, more specifically a shaft of the aforementioned drive on the one hand, and to a second shaft via a second dlsenqagaabie coupling, more speci ically a shaft of a secondary drive on the other hand, whereby the first and second ciaengageable couplings et een the pump and the first shaft and between the um and the second shaft are such that the pump is only driven by the shaft of these two shafts that has the highest speed. An dvan ge is that only one pump has to be provided to the oil, E^tra inlet and outlet pipes do not have to be provided for this pump either, this makes the device sim ler and easier to control,

Anoth advantage is th t there is no switching between different u ps* but that only one pump will take cars of the oil supply, so that changes in the oil supply will foe very small.

Indeed, the changeover of the drive by the secondary drive to the drive of the rotor and vice versa ill proceed seamlessly as it were _*

Moreover,, a complex control will not foe necessary to realise this.

Another ad antage is that the secondary drive can foe used to drive the pump before the drive of the rotor is started, so that the compress r el ment can already b lubricated.

When switching off, the secondary drive can take over the role of the d ive to ensure that the pu can inject sufficient oil,

Γη the most preferred embodiment the first ciisengageahle coupling between the pump and the first shaft is realised b meana of at least one freewheel coupling that is affixed. on the first shaft, and the second disengsgeafoie coupling between the ump and the second shaft is realised by means f at least GOO fr e heel coupling that is affixed on the second shaft , whereby the freewheel co linos ere anon tha when the po has a higher speed than the shaft concerned, the freewheel coupling will disengage the pump- from the shaft concerned _* this has the ad ant ge that the u will be automatically disengaged from the drive w n it has a lower speed than the secondary d ive, whereby the- sec nd ry drive will be ijTunediateiy coupled to the pump and vice versa,

It is clear that the disengageable couplings can be realise in very ma y different ways> T e Invention also concerns a method for providing a compr ssor device with oil by eans of a ump, whereby the pump is coupled o a first shaft of a drive via a first disengageable coupling, whereby this drive also drives a rotor of the compressor device, and is coupled to a second shaft of a secondary drive via a second disengageable coupling, whereby the method comprises the following steps:

~ the determination o the speed of the first shaft and the second shaft ;

- the comparison of the speeds;

- when the speed of the second shaft is greater than the speed of the first shaft, the first disengageable coupling disengage and the second disengageable coupling engages;

- when, the speed of the second shaft is less than the speed of the firs shaft, the second disengageable coupling disengages and the first disengageable coupling engages > An advantage of such a met od is that only one pump is required for such a method to foe able to supply the compressor de ise with oil _*

Such a method will also be easy to implement.

Another additional ad an age is that the quantity of oil that is injected or driven around in the oil circuit vfi.ll. not fluctuate, or as good as no fluctuate, when the c m ressor device is switched on and off because for the operation of the pump the switching between the drive and the secondary drive will foe seamless so to speak, With the intention of better showing the characteristics of the n e ion _? a few preferred variants of a compressor device according to the invention mi a method for supplying a compressor device with oil are described hereinafter by way of an example, without any limiting nature, with reference to the accompanying dra gs, wherein; figure I schematically shows a compressor device according to the invention

figure 2 shows the section indicated by Ρ2 in figure 1 in more detail;

figure 3 shows an alternative embodiment.

The compressor device 1 shown in figure 1 comprises a centrifugal compressor element 2 with a housing 3 in which in this ase two rotors are affixed in he fo m of im llers ,

It is clear tha the com ressor de-vice 1 can com ise a di ferent type of compressor element 2 _f such, as for example a sere¾j compressor element cr turhocomptessot element♦

The housing 3 is provided with at inlet 5 for gas to e compressed and an outlet for compressed gas,

A drive ? is provided in order to drive the impellers „

This dri^e ? comprises a motor 8 with a first shaft S that is coupled to the shaft 10 of the impellers 4 by rseans of a t smission 11 »

In this case, this transmission 11 consists of gearwheels 12 that are a filed o the first shaft 0 and the shaft 10 of the impellers 4.

As can be seen in figure 1, the transmission 11 is integr d in the housing 3, in a space 13 that, is closed off from the space 14 in the bousing 3 where the impellers arc located, he first shaft 9 of the motor 8 xtends through the bousing 3, and the motor 8 itself is outside the housing 3,

The necessary seals IS are provided around the first shaft 9 a d the shaft ID of the impellers _f in order tc ensure the separation between the speoe 13, 14 i the housing 3 and the outside world on the one hand, e d b t een the different s aces 13, 14 o the housing 3 mutually on the other hand,

S T e com ressor device X is fu t e provided with an oil ci cuit 16 to he able to inlect oil. into the com resso device 1 to cool and lubricate the compressor element 2,

In this case the oil will essentially foe used for the0 lubrication and/or cooling of the gearwheels 12 of the transmission 11, or in other words the oil will be injected into the space 13 of the housing 3 where the transmission 11 is loca ed, S If it concerns a screw compressor element, the oil is essentially used for cooling and lubricating the helical rotors ,

The oil circuit 16 comprises an oil reservoir 1? that is0 connected ie oil pipes 18 to an inlet 19 and outlet 20 for oil in the honsinc 3.

Furthermor _f the oil circuit 16 comprises a cooler 21. for cooling the oil and an oil filter 2,

t

Acc rding to the invention the oil circuit 16 only comprises one pump 23 that is connected to the first shaft 9 ^ia a first disengagesble coupling 24» h second ry drive 2$ is also provided n the foria. of an auxiliary mot r 26 with a second shaft 27 that is connected to the p m 23 via a second disengageable coupling 28. &s shown in detail in figure 2 _f the first disengageable coupling 14 is realised hy means of a freewheel coupling 29.

In this case, bat not necessarily,. it concerns two freewheel couplings 23 that are ffined on the first shaft 9, seore specifically on an extended section 30 of the first abaft 9 that extends through the housing 3.

The reewheel coupling 29 is such that when the pu;tp 23 has a higher speed than the first shaft 9 _? the freewheel coupling 29 will disengage the pump 23 from the first shaft 9.

Blocking me ns are provided at the end of the extended. section 30> in this case in the form of a irciip 31, and a spacer 32 is provided between the freewheel couplinga 29 that ensure that the freewheel couplings stay in place.

Analogously the second disengagaafole coupling 28 la realised by means of a freewheel coupling 20 that is affixed on the second s aft 27 _? whereby a circli 31 is aiso provided that acts aa a blocking eans,

¾s can be seen in figure 2, the first shaft 9 and the second shaft 27 are in line with one another. ID

In this way it is possible to affix a bush 33 ve the freewheel couplings 33> whereby the bush 33 is connected to the pump 23. The bueh 33 ac s as it w e as the drive shaft of the m 23, e eb it must be noted that the hush 33 villi follow the mo e ent, i.e. th rotation at a certai speed, of either the first shaft 3 or the second shaft 2? depending on the speed of the shafts 9, 27,

It is clear that in this way the first a d second disengaoeable couplings 24 , 28 are such that the mp 23 is only driven toy the shaft of the wo shafts 9, 27 that has the highest speed .

The operation of the de ice 1 is very simple and as follows.

Daring operation, the motor 8 will drive the first shaft 9. The shaft 10 of the impellers 4 will ho d iven via the transmission 11 , such that the impellers 4 will rotate.

The impellers 4 will hereby draw in air through the inlet 5 and compress it,

The com ressed air will leave the compressor da iae 1 ia the outlet;. 6.

Due to the movement of the fi st shaft 9 the pemp 23 will also he driven by this first shaft 3. Ind ed, du ing the- operation of the mpress device 1 the sec dary drive 25 Is not operating because the auxiliary T¾otor 26 is switched off, his means that the second shaft 27 is not rotating,

A the first shaft 9 will Indeed rotate at a certain speed, the freewheel couplings 23 on this first shaft S will ensure a coupling between the first shaft and the ump 23,

The freewheel couplings 29 on the second shaft 27 will disengage the pump 23 from, the second shaft 27* as the ηϊκ 23 will rotate at a higher speed than th« second shaft 27.

In other wo ds: the thi st diseng&geable pling is engaged, while the second disengageabie coupling is disengaged or uncoupled, The pump 23 is driven b the first shaft 8 of the drive , such that oil will b pumped around in the oil circuit 16 from the oil reservoir 17, so that oil ie brought into the housing 3 via the inlet 19 for oil, more specifically in the space 13 in. which the gearwheels 1 are located,

Hereby the oil first passes through the cooler 21 and the filter 22 to cool the oil if desired and to filter any is-puri ties out of the oil. The oil will return to the oil reservoir 17 via the outlet 20 for oil. A the moment that the com ess r d vic 1 s switched of , in the first instance the secondary dri¾ 25 will be started op. The speed of the second shaft 21 will hereby increase >

Then the drive ? a switched off, such that the speed of the motor 8 and thus the first, shaft 9 will decrease, fo as long as the speed of the first shaft & is higher than the second shaft 2Ί , the first disengageable coupling 24 will ensure that the pump 23 is driven by the first shaft S. A the moment that the speed of the first shaft 0 is lo e than the speed of the second shaft 21 _r the first disengageahle coupling 24 will be disengaged and the second disengageahle coupling £8 will be engaged, Because in this case use is made of freewheel co lings 29, this changeover from the first shaft § to the second shaft 27 will be done automatical Ly without any intervention of controller or regulator. In other words the determination of the speeds of the first shaft 9 and the second shaft and the comparison or those speeds will be done without the intervention, or a controller, regulator or similar. hen the drive 7 is fully switched off, and thus the speed of the first shaft § n the impellers 4 is equal to zero, the pump 23 will still be driven by the auxiliary ssotor 26, s a result while switching off, the necessary oil will still be Injected into the housing 3.

The auxiliary motor 26 can be switched off at the moment that the drive 7 has completely stop d,

When the compressor device 1 has to be started up, In e first instance the secondary drive 2S will b started up.

The pump 23 is then driven by the second shaft 27, such that oil is injected into the ou ing 3, already before the actual start-up of the compressor device 1,

Then the motor 8 is started up, such that the drive 7 comes into operation.

I this v>ay it can be ensured that the gearwheels 12 of the drive 7 are already lubricated before the compressor device 1 is started op, in the first instance the pump 23 sill still be driven by the auxiliary motor 26»·

Only at the time that the first shaft 9 has a higher speed than the second shaft 27 , the second disengsgeabie coupling 28 ¾?iil be diaengaged and the first diaengageabie coupling 24 ¾dli bo engaged, due to the action of the freewheel couplings 2 , s that the m 23 is driven by the first shaft 9 _* t this mome the secondary drive 2S with the auxiliary S motor 6 cars he switched off.

It is clear that such a method will ensure that the changeover from the dri e 7 to the secondary drive 25 in order to drive the pum 23 will proceed seamlessly, andD that the supply of oil or the quantity of oil that is injected will present practically no fluctuations,, if at ail. figure 3 hows an alternative eishodiment of figure 2 _f 5 whereby the coupling between the ump 23 _r the first shaft 9 and the second, shaf 27 is implemented in a similar way.

In this case the first and the second disengageabie coupling 24, 28 are realised by means of s i enable0 couplings,

A first switchabie coupling is between the pump 23 and the first .shaft 9 _? a second switohafele coupling is between the pump 23 and the second shaft 27,

3

Activation m ans 34 are hereby provided that ensure that either the disengageabie coupling 24 with the first shaft 9 or the disengageabie coupling 28 with the second shaft 27 is realised,

0 IS ese activation means 3 can foe a controller 34 for x mpl , such as a hydraulic controller, or an electronic circuit that de rmi es which dls-engageable coupling 2 , 28 isost come into perati on th asis of t e speeds of the fi st shaft 9 and the second eha t 21,

In the exam le shown , the couplings are realised by m ans of ftlotion plates 35 on the first shaft 9 and s c d shaft 27 and coupling plates 36 mating therewith that are affixed on the pump 23, whereby the coupling plates 36 are movable with respect to the friction plates 35,

The controller 34 will hereby control the mo ement of the coupling plates 36 _*

To this end the controller 34 will determine the speed of the first .shaft § and the second shaft 27 and compare these speeds . tihen the speed of the second shaft 27 is greate than the speed of the first shaft the controller 34 will ensure that the first disengageabls coupling 2 is disengaged by moving the coupling plate 36 away frosn the friction plate 35 of the first shaft 3.

The other coupling plate 36 ¾ili be moved to the friction plate 35 of the second shaft, such that the second disengageable coupling 28 is engaged, Ho ver, whan the speed of the second shaft 27 is less than the speed of the first shaft 3, the controller 34 wil ensuro that the second disengagesble coupling 28 is diseng ged; b moving tne coupling plate 36 away from the friction plate 35 of the second shaft 27. The other coupling pia e 36 will be jsoved to the friction plate 3S of the first shaft 9, so that the first disengageabie coupling 24 is engaged.

The further operation is analogous to the embodiment described above,

Another possibility is that the first shaft 9 and the second: shaft 27 are not in line with one another, for example by making use of gearwheel ransm ssions between the m 23 and the first shaft 9 and betwee the pu 23 and the second shaft 27, whereb a switch or similar is provided that ensures that either the gearwheels of the one gearwheel tran mission, or the gearwheels of the other gearwheel ransmission mesh together _*

This switching will be done on the basis of the determined speed of the shafts $ and 27, similar to the example of figure 3. The present in entio is by no means limited to the embodiment described as an exa ple and shown in the dra ings, hot a com ressor device accordi g to the invention and a method for providing a compressor device with oil can be realised in all kinds of variants without departing from, the soope of the invention _*