Patent Application
20240376893
The present invention falls within the field of the production of volumetric compressors. particularly but not exclusively intended for the production of equipment and/or plants for suction/compression of material in liquid, gaseous, solid, powder or slurry form. In particular, the invention relates to a volumetric lobe compressor with improved heat dissipation capability.
State of the Art
In the field of the production of equipment for collecting wet and/or dry materials, volumetric compressors are commonly used such as, for example, those described in the patent applications EP3106611, EP3106610 and EP3332123 in the name of the same Applicant. A volumetric compressor typically comprises a main body defining a work chamber housing two rotors with lobes that are usually straight or helical. The body defines a suction section and a discharge section for discharging an operating fluid and it is closed at the ends by two headers.
Each header comprises a first portion, also defined as bank, connected to the body so as to define a corresponding transverse closing surface for the work chamber. At the first portion the bearings (supports) supporting the rotors are installed so as to allow them to rotate around the corresponding axes. Each header also comprises a second portion, connected to the first portion on the opposite side with respect to the main body. Typically, said second portion is cover-shaped and, once connected to the first portion, defines a volume for an oil bath for lubricating the supports of the rotors installed in the bank.
At a first header, a transmission mechanism, which allows rotation of the rotors, is arranged. This mechanism is operated by an external motor directly or indirectly connected to one of the two rotors. The transmission mechanism is configured so as to allow the two rotors to rotate at the same speed. Said mechanism is arranged in the volume defined by the second portion of said first header so that it is partially immersed in the oil bath contained therein. As it is known, volumetric compressors can operate according to a “pressure” operating mode and according to a “vacuum” operating mode. Typically, in the pressure operating mode the machine compresses the air from the suction section, at atmospheric pressure, to the discharge section with a pressure variation of 1-1.5 Bar. In the “vacuum” operating mode, the compressor compresses the air from the suction section (in depression) to the discharge section typically at atmospheric pressure.
In any case, compression of the air between the suction section and the discharge section is accompanied by an increase in temperature. Therefore, the temperature of the body at the discharge section is markedly higher than the temperature at the suction section, and can even reach 150-170° C. This temperature difference between suction and discharge creates a thermal distortion inside the main body, causing it to bend and elongate on the side of the discharge section. This distortion causes misalignment of the rotor supports and more generally a deterioration in the operating conditions which, among the other drawbacks, reduces the life of the supports.
In addition to this, the heating of the body is obviously also transferred to the headers and in particular to the oil bath contained by the portion configured as a cover. The temperatures of the oil can reach values slightly lower than or equal to those reached in the area of the discharge section (i.e., values in the range 150-170°° C. indicated above) also in a short space of time, depending for example on the rotation speed set for the rotors. These temperature values are critical for the stability of the oil and therefore the oil has to be frequently replaced to guarantee operation of the compressor. Apart from maintenance costs, this aspect is extremely disadvantageous in terms of environmental impact in view of the need to manage and dispose of large amounts of oil.
In order to limit the temperature increase, a first well-known solution provides for introduction of an air flow into the work chamber, the effect of which is to cool the rotors. In particular, the air is introduced into a volume of the work operative chamber defined between two lobes of a rotor and the transverse closing walls defined between the two headers, i.e., a volume that is not in communication either with the suction section or with the discharge section.
In the application EP3106611 in the name of the Applicant, air is injected into the work chamber frontally, i.e. through openings in the main body. In the solution described in EP 3332123, again in the name of the Applicant, the air is injected laterally, i.e. by means of the apertures that pass through the transverse surfaces of the headers delimiting the work chamber in a longitudinal direction. In particular, the first portion of the headers defines a passage through which the air under pressure directly reaches the injection apertures and therefore the work chamber.
The solution described in EP3332123 limits heating of the body and at the same time significantly reduces the pressure fluctuations and/or the fluctuations at the discharge which typically represent a problem in the solutions with frontal injection. However, the solution described in EP3332123 can only be used when the volumetric compressor operates in the “vacuum” operating mode since the pressure (Pc) inside the compressor is lower than the atmospheric pressure (Pa) outside the compressor. In this condition, the injection air can enter from the outside, cooling the compressor body. In the pressure mode, on the other hand, the compressor operates in the opposite condition, i.e. Pc>Pa. Therefore, on one side the injection air cannot naturally enter the compressor and on the other, the air in the compressor tends to flow out of the injection openings. To prevent this air outflow, a check valve has to be provided. Therefore, with reference to temperature limitation, the solution provided in EP 3332123 is wholly ineffective for the pressure operating mode.
Another known solution used to limit the heating entails cooling the body and/or the headers via an air flow that laps their outer surfaces. In this regard, the patent U.S. Pat. No. 6,817,844 describes a compressor in which for each header an air space is defined between the header and a casing that surrounds the header. For each header, this air space is crossed by air forced through a fan installed in the rotation shaft of the rotor operated by the compressor motor. As it crosses the air space, the air removes heat from the outer walls of the header, thus limiting the heating thereof. On the one hand this solution can be used for both operating modes (vacuum and pressure) but on the other, the provision of the air space considerably complicates the design and production of the compressor, making the solution industrially unfeasible.
Other known solutions are described in the patent applications US 2012/0121442 A1 and EP 0 573 063 A1.
US 2012/0121442 Al describes a dry vacuum multistage pump in which the body and rotor are cooled by circulating water inside a plurality of cooling water jackets. The jackets are obtained, respectively, in the front and rear covers, and in the pump body and are arranged around and in the vicinity of the passage of gas circulating inside the pump. The water cooling entails the presence of devices such as, for example, radiator, pipes, pumps, which increase the overall dimensions and weight of the pump, making the solution industrially unfeasible.
EP 0 573 063 A1 describes a bearing lubrication structure for a rotary machine comprising a closed cooling jacket, namely without inlet and outlet, obtained in the casing of the structure and designed to cool the bearing lubrication oil present inside the casing.
From the above, the need therefore emerges for a new technical solution that overcomes the drawbacks described above, in particular limits overheating of the compressor headers regardless of the compressor operating mode.
The main task of the present invention is to provide a volumetric compressor that overcomes the drawbacks indicated above. In this context, a first object of the present invention is to provide a volumetric compressor with improved heat dissipation capabilities, in particular in terms of the headers. A further object, linked to the preceding one, is to provide a compressor in which said heat dissipation concerns in particular the lubricating oil used in the headers for lubricating the supports. A further object is to provide a compressor in which the heat dissipation is obtained in a simple manner and without complicating the structure of the headers. A further object, linked to the preceding one, is to guarantee that the heat is dissipated regardless of the compressor operating mode. Last but not least, a further object is to provide a compressor which is reliable and easy to produce at competitive costs.
The Applicant has found that the task and the objects indicated above can be achieved by providing a chamber (with an inlet and an outlet) that passes through the bank of a corresponding header and by causing a cooling gas to flow in a forced manner through said chamber so as to remove heat from the walls of the bank. In other words, the idea underlying the invention is to define a cooling chamber within the bank so as to remove heat both from the oil bath (at higher temperature) and from the body (at a temperature equal to or lower than the oil bath).
In particular, the task and the objects of the invention are achieved through a volumetric compressor comprising:
According to the invention, the compressor comprises a generator unit for generating a forced flow of gas and, for at least one of said headers, the bank defines a cooling chamber physically separate from the operative chamber and from the inner volume, in which the cooling chamber comprises an inlet and an outlet for said forced flow of cooling gas, in which said inlet communicates with said generator unit so that said cooling chamber is crossed by said forced flow of cooling gas produced by said generator unit.
During its passage inside the cooling chamber, the cooling gas removes heat (through heat exchange by convection) from the walls of the bank and consequently from the lubricating oil bath and/or from the body of the compressor which are in contact with the bank. Advantageously, the cooling chamber is defined inside the bank and is therefore completely integrated in the structure thereof. Furthermore, the cooling chamber is physically isolated from the operative chamber. Therefore, the cooling gas can flow regardless of the compressor operating mode, i.e. during both vacuum and pressure operation.
In accordance with one embodiment, the inlet and the outlet of the cooling chamber are arranged on opposite sides with respect to a reference plane containing the rotation axes of the lobe rotors. This arrangement ensures a more uniform flow of the cooling gas inside the cooling chamber and therefore an equally uniform thermal exchange with the walls of the bank.
In accordance with a possible embodiment, the outlet of the cooling chamber is defined in a position near to the suction section of said body, while the inlet is defined in a position near to the discharge section of said body. Via this arrangement, the gas flowing out of the cooling chamber is substantially in counter-current with respect to the gas flow entering the suction section of the body. This condition improves thermal distribution in the compressor body, reducing the thermal distortion.
In accordance with a possible embodiment, the generator unit generating the forced cooling gas flow comprises at least one operating machine driven independently of said rotors of said compressor. Via this solution the flow rate of the cooling gas through the cooling chamber can be increased as the rotor rotation speed decreases, or vice versa reduced as the rotor rotation speed increases. In short, the cooling gas flow rate can be adjusted according to the greater or lesser overheating that could occur depending on the rotor rotation speed. This solution allows the compressor efficiency to be increased also at low rotation speeds.
According to a possible embodiment, the bank is defined by a first portion and by a second portion connected to each other and configured so as to define, after their connection, said cooling chamber, in which said first portion is connected to the body and said second portion is connected to said cover. The configuration with two bank portions advantageously facilitates the design and definition of the cooling chamber. Furthermore, this configuration facilitates installation of the supports for rotation of the rotors and the definition of channels for lubrication of the supports.
In accordance with a possible embodiment, the second portion of the bank is made of a material having a thermal conductivity higher than the material used to produce the first portion of the same bank. This solution allows dissipation of the lubricating bath heat to be prioritised over that of the body, with the advantage of prolonging the life of the oil. In accordance with an embodiment, on the inner side of one of the two portions of the bank, ribs are defined which develop towards the inside of the cooling chamber, thus increasing the thermal exchange surface with said cooling gas and consequently increasing the heat dissipated
According to a possible embodiment, for each compressor header, the corresponding bank defines a cooling chamber physically separated from the operative chamber and from the corresponding inner volume; each cooling chamber comprises an inlet and an outlet for a cooling gas, and for each cooling chamber the inlet communicates with the generator unit generating said forced flow of cooling gas so that each cooling chamber is crossed by a forced flow of cooling gas.
In accordance with a possible embodiment, the unit generating the forced flow of cooling gas comprises a first operating machine and a second operating machine each of which is directly or indirectly connected to a corresponding bank so that its delivery communicates with the inlet of the corresponding cooling chamber defined by the bank.
Preferably, the two operating machines are arranged on the same side with respect to a reference plane containing the rotation axes of the rotors.
In a possible embodiment, each operating machine is connected to a corresponding bank through a coupling sleeve which connects the delivery of the operating machine to the inlet of the corresponding cooling chamber.
According to another embodiment, the unit generating the forced flow of cooling gas comprises an operating machine and a supply conduit communicating with the delivery of the operating machine and defining two outlet sections each directly or indirectly communicating with an inlet of a corresponding cooling chamber.
The present invention also concerns fixed or movable equipment for the suction of material in liquid, gaseous, solid, powder or slurry form, characterised in that it comprises a volumetric compressor according to any one of the embodiments indicated above.
Further characteristics and advantages of the invention will become evident from examination of the following detailed disclosure of some preferred but non-exclusive embodiments of the volumetric compressor, illustrated by way of non-limiting example, with the support of the attached drawings, in which:
The same numbers and the same reference letters in the figures identify the same elements or components.
With reference to the cited figures, the present invention concerns a volumetric compressor generically indicated by the reference 1. The compressor 1 comprises a body 2 defining an operative chamber 5 (or work chamber 5). The latter develops in a longitudinal direction 100. The body 2 also defines a suction section 51 and a discharge section 52 of the operative chamber 5. The two sections 51, 52 are configured respectively for suction and discharge of an operating fluid, for example air or other gas. The compressor 1 comprises at least two lobe rotors 8A, 8B, in which said lobes 81A, 81B are housed inside the work chamber 5. Each rotor 8A, 8B rotates around a corresponding rotation axis 101A, 101B which is substantially parallel to the longitudinal direction 100 of development of the work chamber 5.
The form of the rotors 8A, 8B is not important for the purposes of the present invention. The rotors 8A, 8B could have straight lobes or alternatively the lobes could develop according to a substantially helical profile, as in the embodiment shown in the figures. Also the number of lobes of the rotors is not important. In fact, the rotors 8A, 8B could have two lobes or three lobes 81A, 81B (as in the solution shown in the figures) or also a greater number of lobes. In any case, the rotors 8A, 8B comprise two end parts 83A-84A, 83B-84B defining the corresponding rotation axis 101A, 101B and a central part between said end parts and defining the lobes 81A, 81B. The parts of the rotors 8A, 8B indicated above are evaluated in the longitudinal direction 100.
The compressor 1 comprises a first header 6 and a second header 6′ connected to the body 2 on opposite sides so as to delimit longitudinally the operative chamber 5. The two headers 6, 6′ support the two rotors 8A, 8B in the area of their end parts 83A-84A, 83B-84B.
More precisely, each header comprises a first part 61, 61′ directly connected to the body 2 and indicated below by the term “bank”. Each header 6, 6′ also comprises a second part 62, 62′ connected to the corresponding bank 61, 61′ and indicated below by the term “cover”. For each header 6, 6′, the corresponding bank 61, 61′ is comprised between the body 2 and the corresponding cover 62, 62′ and supports the two rotors 8A, 8B in the area of their end parts 83A-84A, 83B-84B. Furthermore, for each header 6, 6′, the corresponding cover 62, 62′ is configured so as to define, once it has been connected to the corresponding bank 61, 61′, an inner volume 65, 65′ which can contain, in use, a lubricating oil bath. In practice, said inner volume 65, 65′ is defined, and therefore comprised, between the corresponding cover 62, 62′ and the corresponding bank 61. 61′.
According to the present invention, for at least one of the two headers 6, 6′, preferably for both, the corresponding bank 61, 61′ defines a cooling chamber 70, 70′ physically separate from the work chamber 5 and from the inner volume 65, 65′ defined above. Said cooling chamber 70, 70′ comprises an inlet 71, 71′ and an outlet 72, 72′, communicating with the inlet 71, 71′, respectively to allow a cooling gas (preferably, but not exclusively, air) to enter, flow through and out of the cooling chamber 70, 70′. According to the invention, the inlet 71, 71′ is connected to a forced flow generator unit 21, 22 of the compressor 1, which is configured to generate a forced flow of cooling gas to the inlet 71, 71′ of the cooling chamber 70, 70′. In other words, the forced flow generator unit 21, 22 has the function of forcing the cooling gas into the cooling chamber 70, 70′.
In particular, according to the invention, the inlet 71, 71′ and the outlet 72, 72′ are both configured by the bank 61, 61′ so that the cooling gas flow passes through the cooling chamber 70, 70′ without entering the work chamber 5. As it passes through the cooling chamber 70, 70′, the cooling gas laps the walls of the corresponding bank 61, 61′, removing heat by convection. As better specified below, it has been seen that this solution limits heating of the oil contained in the inner volume 65, 65′ with the advantage of prolonging the life of the oil. In addition to this, the invention leads to a reduction in the heating of the body 2 of the compressor 1, in particular at the discharge section 52. In any case, the cooling chamber 70, 70′ defines an empty space between the body 2 and the warmer portion of the header 6, 6′ containing the lubricating oil. Said empty space, crossed by the cooling gas, forms a type of barrier that limits transmission of the heat from the lubricating oil to the body 2 and vice versa.
In accordance with a preferred embodiment, the inlet 71, 71′ and the outlet 72, 72′ of the cooling chamber 70, 70′ are defined on opposite sides of the bank 61, 61′ with respect to the reference plane 200 defined above. Preferably, the inlet 71, 71′ is defined in a position near to the discharge section 52 of the body 2, while the outlet 72, 72′ is defined in a position near the suction section 51 of the body 2. It has been seen that this solution allows a more uniform distribution of the temperatures inside the body 2 and therefore lower thermal distortion. In fact, the gas flowing out of the cooling chamber 70, 70′ increases the temperature of the area of the body 2 adjacent to the suction section 51, where the operating fluid has a lower temperature than the discharge section 52. At the same time, the cold cooling gas flowing into the cooling chamber 70, 70′ reduces, or in any case does not increase, the temperature of the body 2 at the discharge section 52.
In the context of the present invention, the generator unit generating the forced flow of cooling gas comprises at least one operating machine (for example a blower or a fan) provided with an impeller driven by a motor, for example an electric motor, with the purpose of generating in delivery an air flow to the inlet of the cooling chambers 70, 70′. According to a possible preferred embodiment, said operating machine is driven independently of the rotors 8A, 8B of the compressor 1. In this operating condition, the number of revolutions of the operating machine, i.e. the rotation speed of the corresponding impellers, can be adjusted (i.e. increased or decreased) independently of the rotation speed, i.e. of the number of revolutions of the rotors 8A, 8B.
In the first header 6 a first inner volume 65 can be identified configured between the first bank 61 and the first cover 62. In the second header 6′ a second inner volume 65′ can be identified between the second bank 61′ and the second cover 62′. Both the inner volumes 65, 65′ contain an oil bath for lubricating the supports/bearings 701-701′, 702-702′ mounted on the corresponding bank 61, 61′ and allowing rotation of the rotors 8A, 8B.
According to a possible embodiment, one of the two inner volumes 65, 65′ defined above houses a motion transmission unit 130, configured to mechanically connect the two rotors 8A, 8B. In accordance with a solution known per se, the transmission unit 130 is configured to rotate the rotors 8A, 8B in a synchronous manner but in opposite direction. In the case illustrated in the figures (see in particular
According to another aspect, at least one of the two covers 62, 62′ comprises an opening 620 (indicated in
According to a possible embodiment, the inner volume of the header opposite the header containing the transmission unit 130 houses an oil spreader disc 135 fitted at the end of one of the two rotors, preferably the lower rotor 8A nearest the support plane PO. The function of the oil spreader disc is known per se to a person skilled in the art. With reference to
According to a preferred embodiment, shown in the figures, for each of the two headers 6, 6′, the corresponding bank 61, 61′ defines a corresponding cooling chamber 70, 70′. In particular, a first cooling chamber 70, defined by the first bank 61 of the first header 6, can be identified and a second cooling chamber 70′, defined by the second bank 61′ of the second header 6′, can be identified. Each cooling chamber 70, 70′ comprises a corresponding inlet 71, 71′ and a corresponding outlet 72, 72′ communicating with each other. According to the invention, each inlet 71, 71′ communicates with the flow generator unit so that the inlets 71, 71′ of both the cooling chambers 70, 70′ are supplied with a flow of cooling gas.
With reference to
In an alternative embodiment, not shown in the figures, with respect to the reference plane 200 the inlet 71 and the outlet 72 of the first cooling chamber 70 could be on opposite sides with respect to the inlet 71′ and the outlet 72′ of the second cooling chamber 70′. In this case, also the two blowers 21, 22 could be installed on opposite sides with respect to said reference plane 200.
Preferably the two blowers 21, 22 are driven independently of the rotors 8A, 8B of the compressor 1, i.e. so that the rotation speed of the corresponding impellers can be set regardless of the number of revolutions of the rotors 8A, 8B. Via this solution it is therefore possible to increase the number of revolutions of the blowers 21, 22, i.e. the flow rate of the flows through the cooling chambers 70, 70′, when the rotation speed of the rotors 8A, 8B is low, i.e. when the compressor 1 is subject to greatest heating. Alternatively, it is possible to reduce the flow rate of the flows through the cooling chambers 70, 70′ when the rotation speed of the rotors 8A, 8B is high.
According to an embodiment, the two blowers 21, 22 each comprise a corresponding volute 24, 24′ that guides the flow generated through the corresponding impeller 25, 25′ and defines the delivery of the same blower. As shown in the figures, for each blower 21, 22, a coupling sleeve 41, 41′ is provided to connect the delivery (meaning the volute) 24, 24′ of a blower 21, 22 to the inlet 71, 71′ of the corresponding cooling chamber 70, 70′. For each header 6, 6′ of the compressor 1, the coupling sleeve 41, 41′ is internally hollow and is fixed, at a first side thereof, on the bank 61, 61′ at of the inlet 71, 71′ of the cooling chamber 70, 70′. For each blower 21, 22, the volute 24, 24′ is fixed on a second side of the coupling sleeve 41, 41′, opposite the first, so that the flow generated by the blower 21, 22 in delivery is conveyed into the cooling chamber 70, 70′ through the sleeve itself. Advantageously, the use of a coupling sleeve 41, 41′ allows the use of readily available blowers as it represents a low cost connection interface that is easy to produce.
However, the present invention also comprises the possibility of connecting the volute 24, 24′ of the blower 21, 22 directly to the corresponding bank 61, 61′ without using a coupling sleeve.
According to a possible embodiment shown in
As can be seen in
According to a preferred embodiment shown in the figures, for at least one of the two headers 6, 6′, the corresponding bank 61, 61′ comprises a first portion 61A, 61A′ and a second portion 61B, 61B′ connected to each other, preferably through screw connection means 501-502 (see
In the embodiment shown in the figures, the configuration with two portions of the bank 61, 61′ is adopted for both the headers 6, 6′. In particular, for each bank 61, 61′, the corresponding two portions 61A-61B, 61A′-61B′ are configured so as to define, once they have been joined, the cooling chamber 70, 70′ in accordance with the purposes of the present invention.
More precisely, the cooling chamber 70, 70′ is delimited by an inner side 63, 63′ of the first portion 61A, 61A′ and by an inner side 64, 64′ of the second portion 61B, 61B′. An outer side 67, 67′ of the first portion 61A, 61A′ longitudinally delimits the work chamber 5, while an outer side 68, 68′ of the second portion 61B, 61B′ remains in contact with the oil bath delimiting the corresponding inner volume 65, 65′ of the header 6, 6′. In short, the term “inner” is used to indicate the sides of the portions 61A, 61B-61A′, 61B′ of the bank 61, 61′ that delimit the relative cooling chamber 70, 70′, while the term “onder” is indicated for the sides opposite the inner ones.
According to a possible embodiment, the two portions 61A, 61B-61A′, 61B′ are made of metallic materials having different thermal conductivity. Preferably, the second portion 61B, 61B′ is made of a first material, for example cast iron, having a thermal conductivity greater than a second material, for example steel, with which the first portion 61A, 61A′ is made. This solution is designed to favour dissipation of the heat from the oil bath which is in contact with the outer side of the second portion 61B, 61B′. In fact, although on the one hand the gas flow through the cooling chamber 70, 70′ subtracts heat also from the body 2, on the other hand this solution favours the heat exchange by convection with the second portion 61B, 61B′ of the bank 61, 61′ with greater thermal conductivity.
In an alternative embodiment, falling within the present invention, the two portions 61A, 61B-61A′, 61B′ of the bank 61, 61′ could be made of the same material, i.e. have the same thermal conductivity. In another possible embodiment, the material forming the first portion 61A, 61A′ could have a thermal conductivity higher than the one used for the second portion 61B, 61B′.
In the case illustrated, the second portion 61B is defined by a body that comprises a core part 610B (indicated in
As shown in the figures, according to a possible embodiment, in the lower part 91C of the bank 61, fixing feet 711 can be installed for fixing the compressor 1 (see
In an embodiment, also shown in the figures, in the upper part 91D an eyebolt 715 can be provided to lift the compressor 1 (see
The technical solutions described above with reference to the first bank 61 of the first header 6 are preferably adopted also for the second bank 61′ of the second header 6′, as can be seen also from the section view of
According to a possible embodiment, the inner side of one of the two portions 61A, 61B-61A′, 61B′ of the bank 61, 61′ defines ribs 77 which develop towards the inside of the corresponding cooling chamber 70, 70′ in order to increase the thermal exchange surface with the cooling gas.
In the embodiment shown in the figures, said ribs 77 are defined on the inner side 64, 64′ of the second portion 61B, 61B′ of the bank 61, 61′. Also this arrangement is designed to favour dissipation of the heat from the lubricating bath contained in the inner volume 65, 65′. However, in alternative embodiments, the ribs could be provided on the inner side 63, 63′ of the first portion 61A, 61A′ or on the inner side 63, 64 of both the portions 61A, 61B-61A′, 61B′ of the bank 61, 61′.
The section view of
In particular, the ribs 77 develop according to an arrangement reflecting that of the flow lines followed by the cooling gas as it crosses the cooling chamber 70 from the inlet 71 to the outlet 72 thereof. In particular, said ribs 77 are preferably symmetrical with respect to the first reference plane 200 defined above, and likewise with respect to a second reference plane 250 orthogonal to the first reference plane.
The arrangement shown in
According to a possible embodiment, not shown in the figures, the bank 61, 61′ of one or both the headers 6, 6′ could be made in one single piece. In this case, the cooling chambers 70, 70′ of the two banks 61, 61′ could be defined directly through a fusion process.
The technical solutions described above fully achieve the predefined tasks and objects. In particular, the main effect of the passage of forced air through the cooling chambers 70, 70′ is to limit the thermal level of the lubricating bath contained in the inner volume 65, 65′ of the header 6, 6′ consequently prolonging the life of the lubricating oil.
In this regard, with reference to the compressor 1 shown in the figures, the graph of
From comparison of the two curves in
The graph of
Also from the graph of
The graph of
| Number | Date | Country | Kind |
|---|---|---|---|
| 102021000014648 | Jun 2021 | IT | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2022/055203 | 6/3/2022 | WO |
