Patent Grant
12025356
The present disclosure relates to an oil supply system for a compressor.
An oil injection type compressor, such as a screw compressor, is equipped with an oil supply system for supplying oil to a compression space, a bearing, and the like. After the oil supplied to the compression space is discharged from the compressor along with a compressed gas, the oil is separated from the compressed gas by an oil separator and returned to the compressor again. The oil separated from the compressed gas in the oil separator has a low viscosity due to a dissolved component of the compressed gas. Therefore, if the oil with the decreased viscosity is directly supplied to a bearing and a mechanical seal, a lubricant function and a sealing function may be degraded. As a countermeasure to the above problem, there is a method for using high-viscosity oil to compensate for the decrease in viscosity. However, at the stage where the compressed gas has not yet dissolved and has a low temperature, such as during startup, the viscosity is higher than the appropriate viscosity, which may result in poor lubricant of the bearing or seal failure or the like, or may increase a starting torque of the compressor, resulting in a startup failure.
Patent Document 1 describes a screw compressor where a pressure reducing mechanism is installed in an interconnection pipe for transferring oil, which is separated from a refrigerant (compressed gas) by an oil separator, from an oil sump portion formed at the bottom of the oil separator to a closed vessel, and a pressure of the closed vessel is changed by control of the pressure reducing mechanism to increase/decrease a vaporization amount of the refrigerant dissolved in the oil in the closed vessel, thereby regulating the temperature of the oil supplied to the compressor.
In the screw compressor described in Patent Document 1, the pressure reducing mechanism controls a vapor-liquid equilibrium state in the closed vessel to vaporize the refrigerant dissolved in the oil. In this case, if a retention time of the oil in the closed vessel is short, the oil may be discharged from the closed vessel without sufficient vaporization of the refrigerant in the closed vessel. The vaporization rate of the refrigerant can be improved by increasing the size of the closed vessel and prolonging the retention time of the oil in the closed vessel. However, actual equipment generally has space constraints and cannot prolong the retention time in terms of operating efficiency of the equipment.
The present disclosure was made in view of the above, and an object of the present disclosure is to propose an oil supply system capable of decreasing the amount of the dissolved compressed gas which is contained in the oil supplied to each portion of the compressor in a short time.
An oil supply system for a compressor according to the present disclosure includes an oil separator connected to a discharge pipe of the compressor, an oil tank for receiving oil from an oil sump of the oil separator, an oil pipe disposed between the oil separator and the oil tank, a pressure reducing valve disposed on the oil pipe, an oil supply pipe for supplying the oil to an oil line for supplying the oil to the compressor from an oil sump of the oil tank, and an agitator disposed on the oil pipe.
With an oil supply system for a compressor according to the present disclosure, it is possible to promote separation of a compressed gas dissolved in oil, in an oil pipe disposed between an oil separator and an oil tank. Thus, highly-efficient degassing of the compressed gas from the oil in the oil tank is possible, making it possible to supply the oil, where the amount of the dissolved compressed gas is small and a viscosity is not decreased, to the compressor. Therefore, it is possible to sufficiently maintain a lubricant function in a bearing, a seal portion, and the like of the compressor. Further, even if a retention time of the oil in the oil tank is relatively short, or even if the volume of the oil tank is small, the compressed gas can be degassed from the oil with high efficiency, making it possible to efficiently operate the oil supply system, as well as to reduce the size of the oil tank.
Some embodiments of the present invention will be described below with reference to the accompanying drawings. It is intended, however, that unless particularly identified, dimensions, materials, shapes, relative positions and the like of components described or shown in the drawings as the embodiments shall be interpreted as illustrative only and not intended to limit the scope of the present invention.
For instance, an expression of relative or absolute arrangement such as “in a direction”, “along a direction”, “parallel”, “orthogonal”, “centered”, “concentric” and “coaxial” shall not be construed as indicating only the arrangement in a strict literal sense, but also includes a state where the arrangement is relatively displaced by a tolerance, or by an angle or a distance whereby it is possible to achieve the same function.
Further, for instance, an expression of a shape such as a rectangular shape or a cylindrical shape shall not be construed as only the geometrically strict shape, but also includes a shape with unevenness or chamfered corners within the range in which the same effect can be achieved.
On the other hand, an expression such as “comprise”, “include”, “have”, “contain” and “constitute” are not intended to be exclusive of other components.
Further, the oil supply system 10 includes an oil tank 20 for receiving the oil o accumulated in the lower part of the oil separator 16, and an oil pipe 18 connected to the oil separator 16 and the oil tank 20. The oil pipe 18 is provided with a pressure reducing valve 22 and an agitator 36 (36a, 36b). Further, the oil supply system 10 includes oil lines 24 and 26 for supplying the oil o separated from the compressed gas g to the compressor 12, and an oil supply pipe 28 for supplying the oil o accumulated at the bottom of the oil tank 20 to the oil lines 24 and 26.
In the above configuration, when the oil o accumulated in the oil separator 16 is sent to the oil tank 20 through the oil pipe 18, a pressure is reduced by the pressure reducing valve 22, as well as the oil o is agitated by the agitator 36 and forms a turbulent flow. Thus, since the oil o flowing through the oil pipe 18 is agitated under the reduced pressure, a dissolved component of the compressed gas g dissolved in the oil o starts to be degassed in the oil pipe 18. Further, the dissolved component is degassed from an oil sump surface in the oil tank 20 as well, separating the dissolved component of the compressed gas g from the oil o with high efficiency. Thus, it is possible to supply the oil, where the amount of the dissolved compressed gas g is small and a viscosity is not decreased, from the oil tank 20 to the compressor 12, making it possible to sufficiently maintain a lubricant function in a bearing, a seal portion, and the like of the compressor 12. Further, even if a retention time of the oil o in the oil tank 20 is relatively short, or even if the volume of the oil tank 20 is small, the compressed gas g in the oil o can be separated with high efficiency, making it possible to efficiently operate the oil supply system 10, as well as to reduce the size of the oil tank 20.
Further, conventionally, a method for promoting degassing of a gas-dissolving component by heating the oil o flowing through the oil pipe 18 or the oil o accumulated in the oil tank 20 has also been adopted. However, in the present embodiment, since the highly-efficient separation is possible without adopting such method, there is no need to install a heating device or the like. Furthermore, unlike the conventional case, it is not necessary to use high-viscosity oil, but low-viscosity oil can be used. Thus, during startup of the compressor 12, it is possible to suppress occurrence of poor lubricant, poor sealing, abnormal wear, and the like in the bearing, the seal portion, and the like, and the problem such as an increase in starting torque does not arise. Moreover, since the low-viscosity oil can be used, the viscosity does not increase above a permissible value even if an oil supply temperature is lowered. Therefore, there is no risk that a temperature of a sliding surface of the bearing or the seal portion increases excessively.
In an embodiment, the oil separator 16 and the oil tank 20 form internal spaces, and demisters 30 and 62 are disposed in these internal spaces, respectively. In the oil separator 16, the compressed gas g separated from the oil o has a liquid content such as the oil o removed by the demister 30, and is supplied to the use destination via the pipe 15. In the oil tank 20, the compressed gas g separated from the oil o has a liquid content such as the oil o removed by the demister 62, and is returned to the compressor 12. In the embodiments shown in
Further, in an embodiment, the oil supply pipe 28 includes an oil cooler 32 and an oil filter 34 downstream of the oil cooler 32. The oil o sent from the oil tank 20 to the compressor 12 via the oil supply pipe 28 is cooled in the oil cooler 32, if necessary, and then contaminants are removed in the oil filter 34.
In the embodiments shown in
As another embodiment, if the compressor 12 is, for example, a screw compressor, and includes a slide valve varying a capacity, a balance piston for reducing a thrust load applied to a screw rotor, and the like, an oil line for supplying the oil o to a piston cylinder for operating the above-described components is provided. In this case, since high-pressure oil is required to operate the slide valve and the balance piston, the high-pressure oil is supplied to the above-described oil line by an oil pump 64 disposed on the oil supply pipe 28, the oil lines 24 and 26, which do not require the high-pressure oil very much, are each provided with a throttle valve, and the pressure-reduced oil o is supplied from these oil line to the compressor 12.
In an embodiment, the compressor 12 is applied to a refrigeration system constituting a refrigeration cycle, or a heat pump system constituting a heat pump cycle capable of supplying cold and hot heat to the use destination. When applied to the above-described system, the compressor 12 is disposed on a refrigerant circulation path, and in the embodiments shown in
In an embodiment, as shown in
In an embodiment, as shown in
In an embodiment, as shown in
In an embodiment, as shown in
The turbulator 40 (40b) shown in
The turbulator 40 (40c) shown in
In an embodiment, in addition to the turbulator 40, irregular fillings 80 (80a, 80b, 80c) respectively shown in
Depending on the degree of degassing action required, the irregular fillings 80 may be disposed so as to block the entire side cross-section of the oil pipe 18, or may be disposed so as to block a part of the side cross-section. Further, the irregular fillings 80 may be disposed in the same place as the turbulator 40, or may be disposed in a different place in the axial direction of the oil pipe 18. By disposing the irregular fillings 80 in the place where the turbulator 40 is disposed, it is possible to increase the turbulent flow forming effect, and to increase the agitation effect.
In an embodiment, as shown in
In the embodiment shown in
A portion of the oil pipe 18 provided with the agitator 36 (36a) may be a pipe having a larger diameter than another oil pipe 18, and this pipe may incorporate the turbulator 40 or may include the serpentine channel portion 52. Alternatively, as another embodiment, the portion of the oil pipe 18 provided with the agitator 36 (36b) may be constituted by a pipe having the same diameter as the another oil pipe 18.
Further, the serpentine channel Fm formed in the serpentine channel portion 52 may be filled with the irregular fillings 80. Thus, it is possible to increase the turbulent flow forming effect of the oil o flowing through the serpentine channel Fm, and to increase the agitation effect.
In an embodiment, as shown in
In the exemplary embodiment shown in
The inside of the oil tank 20 has the same pressure as the internal pressure of the oil pipe 18 downstream of the pressure reducing valve 22, which is reduced by the pressure reducing valve 22. Thus, since the inside of the oil tank 20 has the reduced pressure, it is possible to promote the vaporization of the gas-dissolved component of the compressed gas g from the oil o sprayed to the gas phase portion Sg.
In an embodiment, as shown in
By orienting the nozzle port of the jet spray nozzle 38 diagonally upward, it is possible to further prolong the time for the oil o to reach the oil sump. Thus, it is possible to further promote the vaporization of the gas-dissolved component of the compressed gas g from the sprayed oil o.
In an embodiment, as shown in
A flow regulating valve may be provided in the oil pipe 18 separately from the pressure reducing valve 22, and the controller 58 may control the opening of the flow regulating valve to control the amount of the oil o accumulated in the oil separator 16. Thus, the pressure reducing function of the oil o flowing through the oil pipe 18 and the oil level adjusting function of the oil o accumulated in the oil separator 16 may be shared by the different valves.
In an embodiment, as shown in
In the exemplary embodiment shown in
In the embodiment shown in
In an embodiment, as shown in
In the exemplary embodiments shown in
In an embodiment, as shown in
In the exemplary embodiments shown in
In an embodiment, the oil supply system 10 includes a defoaming device 82 for suppressing foams generated on the surface of the oil o accumulated in the lower part of the oil tank 20. With the defoaming device 82, it is possible to extinguish foaming generated on the oil sump surface formed in the lower part of the oil tank 20, and by removing the foams on the oil sump surface, it is possible to promote degassing of the compressed gas g from the oil sump surface. Further, it is possible to control the liquid level of the oil o accumulated in the oil tank 20, without any trouble.
A part of the compressed gas g flowing through the pipe 15 is brought into the nozzle body 84 via the pipe 86. The compressed gas g brought into the nozzle body 84 is horizontally sprayed from the spray holes 88a to the radially outer side of the spray tube 88. The compressed gas g sprayed from the spray holes 88a forms a circulating flow Fcg which goes downward from an inner wall surface of the oil tank 20 and further goes toward a center side in the oil tank 20. Foams f generated on the oil sump surface by the circulating flow Fcg are collected to the center side in the oil tank 20 and are extinguished by the compressed gas g which is sprayed from the spray holes 88a formed in a bottom surface of the spray tube 88.
Further, a controller 102 is disposed in a casing 100 fixed to the base portion 90, and a rod-shaped foam sensor 104 is vertically hung from the base portion 90. If a lower end of the foam sensor 104 touches the foams f, the foam sensor 104 detects the foams f and the detection signal is sent to the controller 102. Upon receiving the detection signal, the controller 102 operates the ultrasonic oscillator 98 to oscillate the ultrasonic waves from the ultrasonic oscillator 98 toward the foams f. Thus oscillating the ultrasonic waves toward the foams f, it is possible to extinguish the foams f. According to the defoaming device 82 (82b), if the foams f reach a predetermined height, the foam sensor 104 detects it and automatically operates to extinguish the foams f.
If the defoaming device 82 (82c) is of an electric heating type, the heater 110 includes a heat transfer wire connected to a conductive wire 116, and the heater 110 is heated by energizing the heat transfer wire of the heater 110 via the conductive wire 116 from a power source (not shown). The foams f generated on the surface Ls of the oil sump disappear by being heated by the heater 110.
If the defoaming device 82 (82c) is of a steam heating type, the heater 110 includes a steam tube into which steam is brought, and the conductive wire 116 includes a steam conduit for supplying steam to the steam tube. By supplying steam to the steam tube of the heater 110 via the steam conduit, the surrounding foams f are heated and extinguished.
With the above configuration, if the compressed gas g is injected from the nozzle 120, a circulating flow Fco of the oil o is formed on the surface Ls of the oil sump by a force of the compressed gas g injected from the nozzle 120. If the circulating flow Fco is formed on the surface Ls of the oil sump, the foams f generated above the surface Ls also circulate in the same direction as the circulating flow Fco. Thus, the foams f sequentially move to a position where the foams hit against the compressed gas g blown out from the nozzle 120, and thus are sequentially blown off by the compressed gas g blown out from the nozzle 120 and disappear.
In an embodiment, a pipe portion of the oil pipe 18 from the pressure reducing valve 22 to a connection end with the oil tank 20 is horizontal or inclined downward toward the downstream side. In
According to the present embodiment, since the downstream pipe portion 18b′ is disposed horizontally or obliquely downstream downward toward the downstream side, a head difference does not occur which offsets the pressure reduction amount by the pressure reducing valve 22 with the oil o flowing through the downstream pipe portion 18b′. Therefore, even if the pressure reduction amount by the pressure reducing valve 22 is increased, it is possible to secure an oil flow toward the oil tank 20 in the downstream pipe portion 18b′. That is, unlike a U-shaped bent portion, the compressed gas g is not trapped. Thus, it is possible to suppress retention of the compressed gas g degassed from the oil o in the downstream pipe portion 18b′, making it possible to suppress that the degassed compressed gas g is redissolved in the oil o during the retention in the downstream pipe portion 18b′. Further, compared to a case where the downstream pipe portion 18b′ is disposed in the vertical direction, it is possible to prolong the retention time of the oil o in the downstream pipe portion 18b′, making it possible to secure a degassing time of the dissolved gas in the downstream pipe portion 18b′.
In an embodiment, the downstream pipe portion 18b is configured to have a larger channel cross-sectional area than the upstream pipe portion 18a. According to the present embodiment, it is possible to increase a pressure-reduced space where the pressure is reduced by the pressure reducing valve 22 in the oil pipe, making it possible to prolong the retention time of the oil o in the pressure-reduced space. Thus, it is possible to further promote degassing of the compressed gas g from the oil o.
In an embodiment, the downstream pipe portion 18b is configured be to longer than half of the full length of the oil pipe 18. According to the present embodiment, since it is possible to increase the pressure-reduced space where the pressure is reduced by the pressure reducing valve 22 in the oil pipe, it is possible to prolong the retention time of the oil o in the pressure-reduced space, making it possible to further promote degassing of the compressed gas g.
The contents described in the above embodiments would be understood as follows, for instance.
1) An oil supply system (10) for a compressor according to an aspect includes an oil separator (16) connected to a discharge pipe (14) of the compressor (12), an oil tank (20) for receiving oil (o) from an oil sump of the oil separator (16), an oil pipe (18) disposed between the oil separator (16) and the oil tank (20), a pressure reducing valve (22) disposed on the oil pipe (18), an oil supply pipe (28) for supplying the oil to an oil line (24, 26) for supplying the oil to the compressor (12) from an oil sump of the oil tank (20), and an agitator (36) disposed on the oil pipe (18).
With the above configuration, when the oil separated from a compressed gas in the oil separator is sent to the oil tank through the above-described oil pipe, a pressure is reduced by the above-described pressure reducing valve, as well as the oil is agitated by the above-described agitator and forms a turbulent flow. With a synergistic effect of the pressure reduction by the pressure reducing valve and the agitation action by the agitator, degassing of the compressed gas dissolved in the oil starts in the oil pipe, making it possible to achieve separation of the oil from the compressed gas in the oil tank with high efficiency. Thus, it is possible to supply the oil, where the amount of gas-dissolving components is small and the viscosity is not decreased, from the oil tank to the compressor, making it possible to secure a lubricant function and a sealing function particularly in a bearing, a seal portion, and the like of the compressor. Further, even if a retention time of the oil in the oil tank is relatively short, or even if the volume of the oil tank is small, it is possible to achieve separation of the oil from the compressed gas with high efficiency. Thus, it is possible to efficiently operate the oil supply system, as well as to reduce the size of the oil tank.
2) The oil supply system (10) for the compressor according to another aspect is the oil supply system for the compressor as defined in 1), where the agitator (36) is disposed on the oil pipe (18) downstream of the pressure reducing valve (22).
With the above configuration, since the oil whose pressure is reduced through the pressure reducing valve is agitated by the agitator, it is possible to promote degassing of the compressed gas dissolved in the oil.
3) The oil supply system (10) for the compressor according to still another aspect is the oil supply system for the compressor as defined in 1) or 2), where the oil pipe (18) is connected to a gas phase portion (Sg) of the oil tank (20).
With the above configuration, since the oil and the compressed gas degassed from the oil flow out from an outlet of the oil pipe to the gas phase portion of the oil tank, it is possible to prevent the compressed gas degassed from the oil from mixing in the oil sump of the oil tank and being redissolved. Further, degassing of the gas-dissolving component, which has not been degassed from the oil, from the oil is also promoted when the gas-dissolving component is released to the gas phase portion.
4) The oil supply system (10) for the compressor according to yet another aspect is the oil supply system for the compressor as defined in any one of 1) to 3), where the oil pipe (18) does not include a temperature regulating device for heating or cooling the oil (o) flowing through the oil pipe (18).
With the above configuration, since the oil pipe (18) does not include the above-described temperature regulating device, it is possible to reduce an equipment cost. The oil supply system for the compressor according to the above embodiment cools the oil by taking latent heat of evaporation from the oil when the compressed gas dissolved in the oil is vaporized, and thus the oil pipe does not require a device for cooling the oil. Further, since the oil supply system for the compressor according to the above embodiment promotes degassing of the compressed gas dissolved in the oil by the pressure reducing valve and the agitator disposed on the oil pipe, the oil supply system does not require a heating device for promoting degassing of the dissolved compressed gas by increasing the temperature of the oil and reducing the solubility of the compressed gas.
5) The oil supply system (10) for the compressor according to yet another aspect is the oil supply system for the compressor as defined in any one of 1) to 4), where the agitator (36) includes a turbulator (turbulent device) (40) disposed in the oil pipe (18).
With the above configuration, it is possible to promote degassing of the compressed gas dissolved in the oil by agitating the oil by causing a turbulent flow in the oil with the turbulator and by causing a pressure loss.
6) The oil supply system (10) for the compressor according to yet another aspect is the oil supply system for the compressor as defined in any one of 1) to 4), where the agitator (36) includes a serpentine channel portion (52) formed in a channel of the oil pipe (18).
With the above configuration, it is possible to promote degassing of the compressed gas dissolved in the oil by agitating the oil flowing through the above-described serpentine channel portion by causing the turbulent flow in the oil and by causing the pressure loss.
7) The oil supply system (10) for the compressor according to yet another aspect is the oil supply system for the compressor as defined in 3), where the agitator (36) includes a spray nozzle (38) disposed on the oil pipe (18) and opened to the gas phase portion (Sg) of the oil tank (20).
With the above configuration, the oil flowing into the oil tank from the oil pipe is sprayed in the form of mist from the above-described spray nozzle to the gas phase portion of the oil tank, making it possible to promote degassing of the compressed gas dissolved in the oil.
8) The oil supply system (10) for the compressor according to yet another aspect is the oil supply system for the compressor as defined in any one of 1) to 7) that includes a liquid level sensor (56) for detecting a liquid level of the oil (o) stored in the oil separator (16) and a control part (58) for controlling an opening of the pressure reducing valve (22) based on a detection value of the liquid level sensor (56).
With the above configuration, the above-described control part can control the amount of the oil accumulated in the oil separator. Thus, it is possible to always control the amount of the oil accumulated in the oil separator to an amount to be supplied to the oil tank. Therefore, it is possible to always secure the amount of the oil stored in the oil tank, and to always secure the oil supplied from the oil tank to the compressor during operation.
9) The oil supply system (10) for the compressor according to yet another aspect is the oil supply system for the compressor as defined in any one of 1) to 8) that includes a gas pipe (60) connecting a gas phase portion (Sg) of the oil tank (20) and a suction space of the compressor (12).
With the above configuration, since the gas phase portion of the oil tank communicates with the suction space of the compressor via the above-described gas pipe, it is possible to return the compressed gas separated from the oil to the suction space of the compressor in the oil tank, as well as it is possible to reduce the pressure in the gas phase portion of the oil tank to the same pressure as the suction space of the compressor. Thus, it is possible to promote degassing of the gas-dissolving component which is dissolved in the oil flowing into the oil tank.
10) The oil supply system (10) for the compressor according to yet another aspect is the oil supply system for the compressor as defined in any one of 1) to 9), where the oil supply pipe (28) includes an oil pump (64).
With the above configuration, since the above-described oil supply pipe includes the above-described oil pump, it is possible to supply, without any trouble, the oil from the oil tank of a low-pressure atmosphere to the compression space of the compressor having the higher pressure than the oil tank and the oil supply portions of the compressor including the bearing portion and the like.
11) The oil supply system (10) for the compressor according to yet another aspect is the oil supply system for the compressor as defined in any one of 1) to 10), where the compressor (12) is constituted by a screw compressor, and the oil line (24, 26) includes at least an oil line (26) for supplying the oil to a bearing of a screw rotor (72, 74) composing the screw compressor.
With the above configuration, it is possible to supply the oil o, where the amount of the dissolved gas-dissolving components is small and the viscosity is not decreased, to the bearing of the screw rotor 72 composing the screw compressor and another oil supply portion. Thus, it is possible to maintain the lubricant effect of the oil supply portion such as the bearing.
12) The oil supply system (10) for the compressor according to yet another aspect is the oil supply system for the compressor as defined in any one of 1) to 11) that includes a defoaming device (82) for suppressing foams (f) which are generated on a surface of the oil (o) accumulated in the oil tank (20).
With the above configuration, it is possible to extinguish foaming generated on the oil sump surface in the oil tank, and by removing the foams on the oil sump surface, it is possible to promote degassing of the compressed gas from the oil sump surface. Further, it is possible to control the liquid level of the oil accumulated in the oil tank, without any trouble.
13) The oil supply system (10) for the compressor according to yet another aspect is the oil supply system for the compressor as defined in any one of 1) or 12), where a pipe portion (18b′) of the oil pipe (18) from the pressure reducing valve (22) to a connection end with the oil tank (20) is horizontal or inclined downward toward a downstream side.
With the above configuration, without a head difference which offsets the pressure reduction amount by the pressure reducing valve occurring in the above-described pipe portion, even if the pressure reduction amount by the pressure reducing valve is increased, it is possible to secure an oil flow toward the oil tank in the above-described pipe portion. Thus, it is possible to suppress retention of the compressed gas degassed from the oil in the above-described pipe portion, making it possible to suppress that the degassed compressed gas is redissolved during the retention. Further, compared to a case where the above-described pipe portion is disposed in the vertical direction, it is possible to prolong the retention time of the oil in the above-described pipe portion, making it possible to secure a degassing time of the dissolved gas in the oil pipe.
14) The oil supply system (10) for the compressor according to yet another aspect is the oil supply system for the compressor as defined in any one of 1) to 13), where a portion (18b) of the oil pipe (18) downstream of the pressure reducing valve (22) has a larger channel cross-sectional area than a portion (18a) of the oil pipe (18) upstream of the pressure reducing valve (22).
With the above configuration, it is possible to increase a pressure-reduced space where the pressure is reduced by the pressure reducing valve in the oil pipe, making it possible to prolong the retention time of the oil in the pressure-reduced space. Thus, it is possible to promote degassing of the compressed gas from the oil.
15) The oil supply system (10) for the compressor according to yet another aspect is the oil supply system for the compressor as defined in any one of 1) to 14), where a portion (18b) of the oil pipe (18) downstream of the pressure reducing valve (22) is longer than half of a full length of the oil pipe (18).
With the above configuration, it is possible to increase a pressure-reduced space where the pressure is reduced by the pressure reducing valve in the oil pipe, making it possible to prolong the retention time of the oil in the pressure-reduced space. Thus, it is possible to promote degassing of the compressed gas from the oil.
| Number | Date | Country | Kind |
|---|---|---|---|
| PCT/JP2019/046580 | Nov 2019 | WO | international |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2020/043970 | 11/26/2020 | WO |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2021/106989 | 6/3/2021 | WO | A |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2760936 | Baker | Aug 1956 | A |
| 5765392 | Baur | Jun 1998 | A |
| 7347301 | Sekiya et al. | Mar 2008 | B2 |
| 20110284671 | Yamamoto | Nov 2011 | A1 |
| 20180023571 | Endo | Jan 2018 | A1 |
| Number | Date | Country |
|---|---|---|
| S5228714 | Feb 1977 | JP |
| S53013653 | Feb 1978 | JP |
| 2003286982 | Oct 2003 | JP |
| 4268251 | May 2009 | JP |
| 4588708 | Dec 2010 | JP |
| 2016161211 | Sep 2016 | JP |
| 20140096444 | Jan 2013 | KR |
| Entry |
|---|
| English KR20140096444 by PE2E Feb. 23, 2023. |
| International Search Report issued in International Application No. PCT/JP2020/043970 mailed Feb. 2, 2021. English translation provided. |
| Written Opinion issued in International Application No. PCT/JP2020/043970 mailed Feb. 2, 2021. |
| International Search Report issued in International Application No. PCT/JP2019/046580 mailed Feb. 18, 2020. English translation provided. |
| Written Opinion issued in International Application No. PCT/JP2019/046580 mailed Feb. 18, 2020. |
| International Preliminary Report on Patentability issued in International Application No. PCT/JP2020/043970 mailed Jun. 9, 2022. English translation provided. |
| English translation of Written Opinion issued in International Application No. PCT/JP2020/043970 mailed Feb. 2, 2021, previously cited in IDS filed May 6, 2022. |
| International Preliminary Report on Patentability issued in International Application No. PCT/JP2019/046580 mailed Jun. 9, 2022. English translation provided. |
| English translation of Written Opinion issued in International Application No. PCT/JP2019/046580 mailed Feb. 18, 2020, previously cited in IDS filed May 6, 2022. |
| Number | Date | Country | |
|---|---|---|---|
| 20220390157 A1 | Dec 2022 | US |
