JP2014145345A - Turbo compressor and turbo refrigerator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a turbo compressor which is activated in a shorter time, and to provide a turbo refrigerator.SOLUTION: A turbo compressor comprises: an electric motor 40; a compression part 50 which is rotated by the electric motor 40 and thereby compresses a refrigerant; a casing 20 which stores the electric motor 40 and the compression part 50 in a storage space 21 where the refrigerant exists and stores a lubrication oil O in a reservoir space 30 formed below the storage space 21; a heater 70 which heats the lubrication oil O in the reservoir space 30; and a cover 100 which covers the heater 70 and divides the lubrication oil O into a heating region H where the heater 70 exists and a non-heating region N which is located at the outer side of the heating region H and communicates with the heating region H.

Description

  The present invention relates to a turbo compressor and a turbo refrigerator provided with the same.

  The turbo chiller is a large-capacity heat source device that is widely used in applications such as large-scale factory air conditioning having a clean room such as an electric / electronics-related factory and district cooling / heating. As the centrifugal chiller, there is known a unit that is formed by unitizing components such as a turbo compressor, a condenser, and an evaporator in the vicinity of each other (see, for example, Patent Document 1).

  Said turbo compressor is provided with the electric motor used as a rotational drive part, and the compression part which has several impeller rotated by this electric motor. These electric motors and compression parts are provided with gears for transmitting the rotation of the electric motors to the compression parts and bearing parts for slidingly supporting the rotating shaft. Lubricating oil stored in an oil tank is supplied to the rotational sliding of these gears and bearings.

Here, when the centrifugal chiller is stopped for a long period of time, the refrigerant may be mixed into the lubricating oil and the viscosity of the lubricating oil may be reduced. If such lubricating oil is supplied to the rotary sliding portion when the turbo refrigerator is started, the original lubricating function of the lubricating oil cannot be exhibited.
On the other hand, in the turbo chiller described in Patent Document 1, for example, the lubricant is heated by a heater before the turbo chiller is started, so that the refrigerant is removed from the lubricant and the viscosity of the lubricant is increased. Is recovering.

JP 2011-026958 A

  By the way, the technique described in Patent Document 1 is configured such that the entire liquid surface of the lubricating oil stored in the oil tank is always in contact with a refrigerant having a high heat transfer coefficient. That is, a refrigerant to be compressed by the impeller and a refrigerant for cooling the electric motor exist above the liquid level of the lubricating oil in the oil tank. Due to the presence of this refrigerant, a part of the amount of heat given from the heater to the lubricating oil is radiated to the refrigerant, and it takes time to heat the lubricating oil. As a result, there has been a problem that the turbo compressor cannot be started quickly after being stopped for a long time.

  This invention is made | formed in view of such a subject, Comprising: It aims at providing the turbo compressor which can be started in a short time, and the turbo refrigerator provided with this turbo compressor.

The present invention employs the following means in order to solve the above problems.
That is, the turbo compressor according to the present invention includes a rotation drive unit, a compression unit that compresses the refrigerant by being rotated by the rotation drive unit, and the rotation drive unit and the compression unit in an accommodation space where the refrigerant exists. A casing for storing lubricating oil in a storage space formed below the storage space, a heater for heating the lubricating oil in the storage space, and the lubricating oil in the storage space in the storage space Lubricating oil circulating part to be supplied to at least one rotational sliding part of the rotational driving part and the compressing part, and provided in the casing, immersed in the lubricating oil dripped and stored in the storage space from the rotational sliding part And a cover that covers the heater and divides the lubricating oil into a heating region where the heater exists and a non-heating region outside the heating region communicating with the heating region. It is characterized in.

  According to the turbo compressor having such a feature, only the lubricating oil in the heating region inside the cover is heated, so that the lubricating oil in the heating region can be efficiently heated. Further, since the lubricating oil in the non-heated area outside the cover is not heated, the amount of heat released from the liquid surface of the lubricating oil to the refrigerant can be reduced.

  Further, the lubricating oil circulation part of the turbo compressor according to the present invention is provided so as to be immersed in the lubricating oil in the storage space, and a pump for sucking the lubricating oil to the outside of the casing, and a pump sucked by the pump Preferably, the pump has a lubricating oil flow path that guides the lubricating oil that has been supplied from the upper part of the casing to the rotating sliding portion, and the pump is disposed in the heating region.

  Since the pump is disposed in the heating region, only the heated lubricating oil can be supplied to the rotary sliding portion of the compression portion and the driving portion.

Furthermore, in the turbo compressor according to the present invention, it is preferable that the first end side of the heating region communicates with the non-heating region, and the pump is disposed on the second end side in the heating region.
As a result, the lubricating oil introduced into the heating region from the first end side of the heating region is heated by the heater and then discharged to the outside from the second end side by the pump. Therefore, the sufficiently heated lubricating oil can be supplied to the rotating sliding portion.

  Further, in the turbo compressor according to the present invention, the cover has a cylindrical shape extending over the first end and the second end, and the heater extends inside the cover along the extending direction of the cover. The cover may further include a fin that is provided on at least one of the inner peripheral surface of the cover and the outer peripheral surface of the heater and has a spiral shape toward the extending direction of the cover and the heater.

  As a result, the lubricating oil introduced into the heating region flows toward the pump according to the fin spiral, so that the flow path of the lubricating oil can be increased. Therefore, it is possible to supply the lubricating oil that has been further sufficiently heated to the rotation supply unit.

  Further, the heater of the turbo compressor according to the present invention includes a heat transfer portion provided integrally with the casing so as to protrude from the inner surface of the casing, and is formed in the heat transfer portion and is provided in an external space of the casing. And a heater main body disposed in the insertion hole that communicates.

  Accordingly, the maintenance of the heater body can be easily performed while the lubricating oil can be efficiently heated by the heater.

  In the turbo compressor according to the present invention, it is preferable that a hollow portion is formed inside the cover.

  Thereby, since the heat insulation effect of the heating area | region and non-heating area | region by a cover can be improved, the inside of a heating area | region can be heated more efficiently.

  Furthermore, in the turbo compressor according to the present invention, at least a part of the cover may be a perforated plate.

  Thereby, the refrigerant | coolant isolate | separated from this lubricating oil by heating lubricating oil can be discharge | released from a heating area | region to a non-heating area | region through the hole of a perforated plate.

In addition, a turbo refrigerator according to the present invention includes any one of the above turbo compressors.
Thus, as described above, the lubricating oil in the heating region can be efficiently heated, and the amount of heat released from the liquid surface of the lubricating oil to the refrigerant can be reduced.

  According to the turbo compressor and the turbo refrigerator of the present invention, the lubricating oil in the heating region can be efficiently heated and the amount of heat released from the liquid surface of the lubricating oil to the refrigerant can be reduced. As a result, the temperature of the lubricating oil supplied to the rotary sliding portion by the heater can be raised in a short time, so that the turbo compressor and the turbo refrigerator can be started in a short time.

1 is a schematic system diagram of a turbo refrigerator according to a first embodiment of the present invention. It is a typical longitudinal section of the turbo compressor concerning a first embodiment of the present invention. FIG. 3 is a cross-sectional view taken along the line AA in FIG. 2. It is a typical principal part longitudinal cross-sectional view of the turbo compressor which concerns on 2nd embodiment of this invention. It is a longitudinal cross-sectional view of the cover of the turbo compressor which concerns on the modification of 2nd embodiment of this invention. It is a typical principal part longitudinal cross-sectional view of the turbo compressor which concerns on 3rd embodiment of this invention. It is BB sectional drawing of FIG. It is a longitudinal cross-sectional view of the cover of the turbo compressor which concerns on a 2nd modification.

Hereinafter, a first embodiment of the heat exchanger of the present invention will be described in detail with reference to FIGS. 1 to 3.
As shown in FIG. 1, the turbo refrigerator 1 of the present embodiment includes an evaporation unit 2, a turbo compressor 10, a condensing unit 4, and an intermediate cooling unit 6.

  In the evaporation unit 2, the refrigerant liquid (for example, an organic refrigerant such as fluorocarbons) takes the heat of evaporation from the cold water flowing in the tube 3, evaporates and vaporizes, and is led out of the evaporation unit 2 as a refrigerant gas.

The turbo compressor 10 sucks the refrigerant gas generated in the evaporation unit 2 and compresses the refrigerant gas in two stages by a two-stage impeller 54 that is rotated by the electric motor 40. As a result, the refrigerant gas is in a high-temperature and high-pressure state in which heat from compression is added in addition to the heat of evaporation taken from the cold water in the evaporation unit 2. Note that the refrigerant gas from the intermediate cooling unit 6 is also sucked into the second stage impeller 54.
In the condensing unit 4, the high-temperature and high-pressure refrigerant gas discharged from the turbo compressor 10 is condensed and liquefied again by releasing evaporation heat and compression heat contained in the cooling water flowing in the tube 5. At this time, the cooling water is heated by heat exchange in the condensing unit 4 and then led out of the condensing unit 4.

In the intermediate cooling unit 6, a part of the refrigerant liquid supplied from the condensing unit 4 is reduced in thickness to an intermediate pressure by a first-stage orifice (not shown), expanded and evaporated, and the resulting refrigerant gas is passed through the pipe line 7. Then, the air is sucked into the second stage impeller 54 of the turbo compressor 10. At this time, the refrigerant gas takes away latent heat of evaporation from the remaining refrigerant liquid discharged from the condensing unit 4 and has an effect of lowering the temperature of the refrigerant liquid, and the refrigerant gas separated by the intermediate cooling unit 6 is Mixing with the refrigerant gas compressed by the first stage impeller 54 and having a high temperature has the effect of lowering the temperature of the refrigerant gas sucked into the second stage impeller 54. Thus, by providing the intermediate cooling part 6, both the effect of increasing the amount of refrigeration per unit refrigerant amount and the effect of reducing the power of the compressor are obtained, and the energy saving effect is enhanced.
At the same time, the intermediate cooling unit 6 has a function of maintaining a constant pressure difference between the condensing unit 4 and the evaporating unit 2. For this reason, the flow rate of the refrigerant gas supplied to the turbo compressor 10 via this pipe line 7 is adjusted by interposing the intermediate suction valve 8 in the pipe line 7.

Next, details of the turbo refrigerator 1 outlined above will be described.
As shown in FIG. 2, the turbo compressor 10 includes a casing 20, an electric motor 40 (rotation drive unit), a compression unit 50, a cover 100, a heater 70, and a lubricating oil circulation unit 80.
The casing 20 is a member that forms the external appearance of the turbo compressor 10, and an accommodation space 21 and a storage space 30 are formed therein.

  The accommodation space 21 is a space formed in the upper part in the casing 20, and is partitioned into a first accommodation space 22 and a second accommodation space 23 in the horizontal direction by a partition wall 24 extending in the vertical direction. The partition wall 24 is formed with a through hole 25 that penetrates the partition wall 24 in the horizontal direction and communicates the first storage space 22 and the second storage space 23. A seal member 26 is provided on the inner periphery of the through hole 25 to seal between a drive shaft 43 and a through hole 25 of the electric motor 40 described later.

  The storage space 30 is a space formed in the lower part of the casing 20, that is, a space formed below the accommodation space 21, and contains a lubricating oil O that serves as a lubricant for a rotary sliding portion described later. Yes. The lubricating oil O is stored up to a predetermined water level in the storage space 30. In the present embodiment, the storage space 30 is formed immediately below the second storage space 23 out of the first storage space 22 and the second storage space 23, and the second storage space 23 and the storage space 30 are mutually connected. It communicates vertically.

The electric motor 40 includes a stator 41, a rotor 42, a drive shaft 43, a drive gear 44 (rotational sliding portion), and an electric motor bearing 45 (rotational sliding portion).
The stator 41 has a cylindrical shape in which a central axis is disposed in the horizontal direction, and generates a rotating magnetic field centered on the central axis by an electric current supplied from the outside.
The rotor 42 has a cylindrical shape that is coaxially disposed inside the stator 41, and is rotated around the central axis according to the rotating magnetic field of the stator 41.

  The refrigerant gas is supplied into the first accommodation space 22 that accommodates the stator 41 and the rotor 42 of the electric motor 40 through the refrigerant supply port 27 provided in the casing 20. The refrigerant gas cools the stator 41 and the rotor 42 and then is discharged to the evaporation unit 2 through the refrigerant discharge port 28 provided in the casing 20.

  The drive shaft 43 has a cylindrical shape that is integrally and coaxially fixed inside the rotor 42, and the through hole 25 of the partition wall 24 in the casing 20 extends horizontally from the first storage space 22 side to the second storage space 23. It penetrates in the direction. The drive shaft 43 is rotationally driven around its central axis along with the rotation of the rotor 42.

The electric motor bearing 45 slides and supports the drive shaft 43 of the electric motor 40 and is integrally fixed in the casing 20. In the present embodiment, a pair of motor bearings 45 are disposed on both sides of the rotor 42 in the drive shaft 43.
The drive gear 44 is provided in the second accommodating space 23 so as to project outward from the outer peripheral surface of the drive shaft 43 in the radial direction, and gear teeth are formed on the outer peripheral surface. The drive gear 44 is rotationally driven together with the drive shaft 43.

The compression unit 50 includes a driven shaft 51, a compression unit bearing 52 (rotation sliding portion), a driven gear 53 (rotation sliding portion), and two impellers 54.
The driven shaft 51 is disposed so that the entirety of the driven shaft 51 is accommodated in the second accommodation space 23, and has a cylindrical shape that extends in the horizontal direction and rotates about the axis.
The compression part bearing 52 is integrally fixed in the casing 20 and supports the driven shaft 51 so as to be rotatable about an axis. In the present embodiment, a pair of compression portion bearings 52 are provided apart from each other in the axial direction of the driven shaft 51.

The driven gear 53 is provided integrally with the driven shaft 51 so as to project radially outward from the outer peripheral surface of the driven shaft 51. In the present embodiment, the driven gear 53 is provided so as to be sandwiched between the pair of compression portion bearings 52 from the axial direction.
The gear teeth on the outer peripheral surface of the driven gear 53 are meshed with the gear teeth of the drive gear 44, whereby the driven gear 53 also rotates in accordance with the rotation of the drive gear 44, and the driven shaft fixed integrally with the driven gear 53. 51 is rotationally driven.

As the impeller 54, a total of two impellers 54 including a first-stage impeller 54 and a second-stage impeller 54 are provided. These two impellers 54 are respectively fixed integrally to the outer peripheral surface of the driven shaft 51. As a result, the two impellers 54 rotate around the axis along with the rotation of the driven shaft 51. At this time, the refrigerant gas introduced from the evaporation unit 2 into the second housing space 23 of the casing 20 in the turbo compressor 10 through the refrigerant gas supply channel 61 is compressed in two stages by the impellers 54. The compressed refrigerant gas is sent out to the condensing unit 4 via the refrigerant gas discharge channel 62.
Note that the refrigerant gas leaked from the impeller 54 is present throughout the second accommodating space 23.

  The cover 100 is provided so as to be immersed in the lubricating oil O in the storage space 30, and divides the lubricating oil O into a heating region H and a non-heating region N. 2 and 3, this cover has an inverted U shape extending in the horizontal direction, and a first end 101 which is one end side (the right side in FIG. 2, the front side in FIG. 3) is The other end (the left side in FIG. 2, the back side in FIG. 3) is fixed to the inner surface of the casing 20. Further, the lower end of the cover 100 is fixed to the bottom surface of the casing 20. And the substantially rectangular parallelepiped area | region of the casing 20 arrange | positioned in this way is made into the heating area | region H, and parts other than the heating area | region H in the lubricating oil O are made into the non-heating area | region N.

  As a material for forming the cover 100, a material having a certain degree of strength and low thermal conductivity is suitable, and stainless steel is particularly preferably used. Further, in consideration of the manufacturing cost or the like, a steel plate other than stainless steel, an alloy plate, a resin plate, or the like may be employed as the material of the cover 100.

The heater 70 is provided so that a heater body 71 serving as a heating portion thereof is positioned in the storage space 30 in the casing 20. In this embodiment, the entire heater body 71 is lubricated in the storage space 30. It is immersed in oil O. In the heater 70, for example, the heater body 71 generates heat based on Joule heat when current is supplied from the outside, thereby heating the lubricating oil O.
The heater main body 71 of the present embodiment is disposed in the heating region H, and more specifically, extends horizontally in the first end 101 side with the second end 102 side of the cover 100 as a fixed portion. .

The lubricating oil circulation unit 80 includes a pump 81 and a lubricating oil flow path 82.
The pump 81 is disposed in the storage space 30 in the casing 20, and is entirely immersed in the lubricating oil O. The pump 81 is driven to suck out the lubricating oil O stored in the storage space 30 to the outside of the casing 20.
In the present embodiment, the pump 81 is disposed in the heating region H, and more specifically, is fixed to the inner surface of the casing 20 located on the second end 102 side of the cover 100 in the heating region H. .

  One end of the lubricating oil passage 82 is connected to the outlet of the lubricating oil O in the pump 81, whereby the lubricating oil O sucked by the pump 81 is introduced into the lubricating oil passage 82. One end of the lubricating oil flow path 82 is connected above the casing 20 in communication with the inside of the casing 20. Therefore, the lubricating oil O sent into the lubricating oil flow path 82 by the pump 81 is sequentially supplied into the casing 20 from above the casing 20.

  In the present embodiment, the other end of the lubricating oil passage 82 is connected so as to communicate with the second accommodation space 23 in the casing 20. Thereby, the lubricating oil O pours into the second accommodation space 23 from above. The lubricating oil O supplied into the second housing space 23 in this way serves as a lubricant for the rotational sliding portions such as the compression portion bearing 52 and the driven gear 53 of the compression portion 50, as well as the lubricating oil O. A part moves into the 1st accommodation space 22 via the channel which is not illustrated, and plays a role as a lubricant of rotation sliding parts, such as motor bearing 45 of this 1st accommodation space 22.

Next, the operation of the turbo refrigerator 1 having the above configuration will be described.
When the turbo chiller 1 is stopped for a long period of time and then started, the lubricating oil O in the storage space 30 is first heated by the heater 70. By this heating, the refrigerant dissolved in the lubricating oil O is removed from the lubricating oil O and the viscosity of the lubricating oil O is recovered, so that the lubricating effect of the rotating sliding portion by the lubricating oil O is exhibited. Therefore, the process of heating the lubricating oil O to a predetermined temperature by the heater 70 is performed.

  Then, after the temperature of the lubricating oil O rises to a predetermined temperature, the lubricating oil O is supplied to each rotary sliding portion via the lubricating oil passage 82 by driving the pump 81. Thereby, the electric motor 40 and the compression part 50 can be driven smoothly. Then, the lubricating oil O that exerts a lubricating effect at the rotary sliding portion is dropped from the rotary sliding portion onto the non-heated region N of the lubricating oil O stored in the storage space 30, and then the cover 100 It is introduced into the heating region H through the one end 101. In this way, the lubricating oil O circulates between the storage space 30 and the rotating sliding portion while being heated in the storage space 30.

According to the present embodiment, the heater main body 71 in the lubricating oil O is covered by the cover 100, that is, the heater main body 71 is disposed in the heating region H inside the cover 100, and thus the heater main body 71 is heated. The lubricating oil O to be used is only the lubricating oil O in the heating region H. Accordingly, the lubricating oil O in the heating region H can be efficiently heated as compared with the case where the entire lubricating oil O is heated. Therefore, the temperature of the lubricating oil O can be raised more quickly to a predetermined temperature.
Furthermore, only the heating area H inside the cover 100 is heated, so that the non-heating area N outside the cover 100 is not heated and the low temperature state is maintained. For this reason, since the temperature difference between the refrigerant gas in the second storage space 23 and the lubricating oil O liquid surface does not increase, convective heat transfer from the lubricating oil O to the refrigerant gas can be reduced, and the lubricating oil The amount of heat released from O to the refrigerant gas can be reduced.
Therefore, since the lubricating oil O can be raised to a predetermined temperature in a short time, it is possible to shorten the time until the turbo chiller 1 is restarted, that is, until the electric motor 40 and the compressor 50 are driven. .

  Further, since the pump 81 is disposed in the heating region H, only the lubricating oil O in the heating region H in a state in which the refrigerant gas heated by the heater 71 and the refrigerant gas dissolved therein is separated and has an appropriate viscosity is rotated. It can be supplied to the sliding part. As a result, only lubricating oil having a viscosity suitable as a lubricant can be sent to the rotary sliding portion, and smoother driving can be performed.

  Further, since the pump 81 is disposed on the second end 102 side of the cover 100 in the heating region H, the lubricating oil O introduced into the heating region H from the first end 101 side of the heating region H is supplied by the heater 70. After heating, it is discharged to the outside by the pump 81 from the second end 102 side. Therefore, it is possible to supply the rotating sliding portion with the lubricating oil that has been sufficiently heated to separate the refrigerant gas and has an appropriate viscosity.

  It is also possible to drive the pump 81 simultaneously with the heating by the heater 70, heat the circulating oil O while circulating it, and start the compressor 10 when the lubricating oil O reaches an appropriate temperature. In this case, the lubricating oil O may be circulated through the lubricating oil flow path 82 during normal operation of the compressor, or may be separately installed by branching from the lubricating oil flow path 82 so as to be used only when starting up. Then, the bypass channel 83 installed so as to return to the storage space 30 may be circulated again. Note that the circulation of the lubricating oil O in the bypass passage 83 is performed by operating a switching valve 84 installed at a branch portion from the lubricating oil passage 82 to the bypass passage 83. According to this method, the lubricating oil O in the storage space 30 is forcibly agitated, so that the convective heat transfer rate from the heater to the lubricating oil O is improved, and the flow by the pump 81 in addition to the heating by the heater 70. The heat generation effect of the lubricating oil itself due to work is also added, and the target temperature can be reached in a shorter time.

Next, a second embodiment of the present invention will be described with reference to FIGS. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
The turbo chiller 1 of the second embodiment is different from the first embodiment in the configuration of the cover 110, the heater 70, and the pump 81.

  The cover 110 of the present embodiment is provided so as to be immersed in the lubricating oil O in the storage space 30 as in the first embodiment, and the lubricating oil O is heated to the heating region H and the non-heating region N. Partition. As shown in FIG. 4, the cover 110 has a horizontally extending cylindrical or prismatic shape, and the opening of the first end 111 that is one end side (the right side in FIG. 4) communicates with the non-heating region N. The other end (left side in FIG. 4) is fixed to the inner surface of the casing. That is, the cover 110 has a cylindrical shape extending over the first end 111 and the second end 112. And the cylindrical area | region in the casing arrange | positioned in this way is made into the heating area | region H, and parts other than the heating area | region H in the lubricating oil O are made into the non-heating area | region N.

  Further, the heater main body 71 of the heater 70 has a columnar shape extending in the horizontal direction as in the first embodiment. In the present embodiment, the opening from the first end 111 of the cover 110 toward the second end 112 is performed. It is arranged to be inserted. That is, the base end portion of the heater body 71 is fixed to a surface of the inner surface of the casing 20 that faces the first end 111 of the cover 110, and the heater body extends from the surface toward the inside of the casing 20. 20 and substantially coaxial. Note that the tip of the heater body 71 does not reach the second end 112 of the cover 110.

  On the other hand, the base end of the pump 81 is fixed to the inner surface of the casing 20 located on the second end 112 side of the cover 110 in the heating region H. Accordingly, the tip of the pump is arranged in the heating region H so as to face the tip of the heater body 71.

  According to the turbo compressor 10 of the second embodiment, since the pump 81 is disposed on the second end 112 side of the cover 110 in the heating region H, the heating is performed from the first end 111 side of the heating region H. After the lubricating oil O introduced into the region H is heated by the heater, it is discharged to the outside by the pump 81 from the second end 112 side. That is, heat is exchanged with the heater main body 71 on the outer peripheral side of the heater main body 71, the temperature becomes high, and the refrigerant gas dissolved therein is separated to efficiently bring out the lubricating oil O having an appropriate viscosity to the outside. Can do. As a result, the lubricating oil O that is more sufficiently heated and has an appropriate viscosity can be supplied to the rotating sliding portion.

As a modification of the second embodiment, for example, as shown in FIG. 5, a spiral fin 113 may be provided on the inner peripheral surface of the cover 110. That is, the fin 113 has a spiral shape that twists in the circumferential direction of the cover 110 as it extends in the extending direction of the cover 110 and the heater body 71, that is, in the axial direction of the cover 110.
In this case, since the lubricating oil O introduced into the heating region H flows toward the pump 81 according to the spiral of the fin 113, the flow path of the lubricating oil O can be increased. Therefore, the lubricating oil O heated more sufficiently by the heater 70 and having an appropriate viscosity can be supplied to the rotation supply unit.

Next, a third embodiment of the present invention will be described with reference to FIGS. In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
This embodiment is different from the first embodiment in the configuration of the heater 70.
That is, in this embodiment, the cover has an inverted U shape with the first end 101 opened as in the first embodiment. On the other hand, the heater 70 has a heat transfer section 72 in addition to the heater body 71.

That is, the heater 70 has a bar shape extending in a horizontal direction in a columnar shape, as in the first embodiment.
On the other hand, the heat transfer part 72 is provided integrally with the casing 20 so as to protrude from the inner surface of the casing 20 in the storage space. More specifically, the heat transfer section 72 extends into the cover 100 from the surface of the casing 20 that faces the first end 101 of the cover 100, and the bottom surface thereof is integrated with the bottom surface of the casing 20. The cross-sectional shape orthogonal to the direction in which the heat transfer section 72 extends has a substantially rectangular shape extending upward from the bottom surface of the casing 20. That is, the heat transfer section 72 has a block shape of an inverted substantially rectangular parallelepiped, and the cover 100 is integrally fixed to the surface of the casing 20 facing the first end 101 of the cover 100 and the surface of the casing 20. Intrusions inside. As shown in FIG. 7, a heating region H having an inverted U shape is formed between the inner peripheral surface of the cover 100 and the outer peripheral surface of the heat transfer portion 72, and the first end of the cover 100 is formed. Lubricating oil O is introduced into the heating region H from the opening 101.

The heat transfer section 72 is preferably formed of a material having a high heat transfer coefficient, like the casing 20.
Further, an insertion hole 73 is formed in the heat transfer section 72 so as to be drilled from the outer surface of the casing 20 toward the extending direction of the heat transfer section 72. The insertion hole 73 communicates with the outside of the casing. The heater body 71 is removably inserted into the insertion hole 73 from the outside of the casing 20.

  Moreover, the pump 81 of this embodiment is provided in the lubricating oil O at the 2nd end 102 side of the cover 100 so that the heat-transfer part 72 may be opposed like 2nd embodiment.

In the present embodiment, the heat generated by the heater body 71 is transmitted to the lubricating oil O via the heat transfer unit 72. Thereby, compared with the case where the lubricating oil O is directly heated by the heater body 71, the contact area between the lubricating oil O and the heater 70 can be increased, so that the lubricating oil O can be heated more efficiently. Can do.
Moreover, since the heater main body 71 can be easily taken out from the outer surface of the casing 20, the heater main body 71 can be easily replaced and maintained.

  In the second embodiment, as in the first embodiment, the pump 81 is driven simultaneously with the heating by the heater 70 and heated while circulating the lubricating oil O. When the lubricating oil O reaches an appropriate temperature, the compressor 10 is turned on. It may be activated. Further, similarly to the first embodiment, the lubricating oil O may be circulated by providing the bypass flow path 83 and the switching valve 84.

  The embodiment of the present invention has been described above, but the present invention is not limited to this, and can be appropriately changed without departing from the technical idea of the present invention.

  As a modification, for example, hollow portions may be formed inside the covers 100 and 110. In addition, this hollow part may be formed in a part of cover 100,110, and may be formed in the whole region. In this case, the heat of the heating region H can be prevented from being transferred to the non-heating region N via the covers 100 and 110 by the hollow portion exhibiting a heat insulating effect.

  As a second modification, for example, as shown in FIG. 8, at least a part of the covers 100 and 110 may be a perforated plate in which a punching metal or a net-like hole 121 is formed. Each hole may have a check valve 122. The check valve 122 allows air bubbles to flow from the inside (heating region H) side to the outside (non-heating region N) of the covers 100 and 110 in the hole 121. In this case, the refrigerant gas bubbles separated from the lubricating oil O when the lubricating oil O is heated by the heater 70 are discharged from the heating region H to the non-heating region N through the perforations (holes 121) of the perforated plate. it can. As a result, it is possible to supply the rotating sliding portion with the lubricating oil O having an appropriate viscosity that can reduce the melting of the refrigerant gas into the lubricating oil O and achieve a more lubricating effect.

  Furthermore, a partition cover that partitions the storage space and the second storage space so as to cover the liquid surface of the lubricating oil O may be provided. Accordingly, it is possible to avoid direct contact between the liquid surface of the lubricating oil O and the refrigerant gas in the second accommodation space, and thus it is possible to avoid convective heat transfer from the lubricating oil O to the refrigerant gas. In this case, it is preferable that a lubricating oil passage portion such as a hole for guiding the lubricating oil O dropped from the rotary sliding portion to the storage space 30 is formed in a part of the partition cover. Thereby, the heat radiation from the lubricating oil to the refrigerant gas can be reduced without hindering the circulation of the lubricant.

  The fins 113 may be provided not only on the inner peripheral surface of the cover 110 but also on the outer peripheral surface of the heater body 71 in a spiral shape. Further, fins may be provided on the inner surface of the storage space 30 of the casing 20.

  In addition, although embodiment demonstrated the example which applied the turbo compressor 10 to the turbo refrigerator 1, you may apply the turbo compressor 10 to another apparatus.

  Further, the compressor targeted by the present invention is not limited to the one having the drive gear 44 and the driven gear 53 described above, but can be applied to a direct-coupled compressor in which the electric motor 40 and the driven shaft 51 are directly connected. Further, the present invention is not limited to a compressor having no intermediate cooling unit 6 or a two-stage compressor having two stages of impellers, but can be applied to a single-stage or multistage compressor.

DESCRIPTION OF SYMBOLS 1 Turbo refrigerator 2 Evaporating part 3 Tube 4 Condensing part 5 Tube 6 Intermediate cooling part 7 Pipe line 8 Intermediate suction valve 10 Turbo compressor 20 Casing 21 Accommodation space 22 First accommodation space 23 Second accommodation space 24 Partition 25 25 Through-hole 26 Seal member 27 Refrigerant supply port 28 Refrigerant discharge port 30 Storage space 40 Electric motor (rotation drive unit)
41 Stator 42 Rotor 43 Drive shaft 44 Drive gear (rotating sliding part)
45 Motor bearing (rotating sliding part)
50 Compressor 51 Driven shaft 52 Compressor bearing (Rotating sliding part)
53 Driven gear (Rotating sliding part)
54 Impeller 61 Refrigerant gas supply flow path 62 Refrigerant gas discharge flow path 70 Heater 71 Heater main body 72 Heat transfer part 73 Insertion hole 80 Lubricant oil circulation part 81 Pump 82 Lubricant oil flow path 100 Cover 101 First end 102 Second end 110 Cover 111 First end 112 Second end 113 Fin 121 Hole 122 Check valve O Lubricating oil H Heating area N Non-heating area

Claims (8)

A rotation drive unit;
A compression unit that compresses the refrigerant by being rotated by the rotation drive unit;
A casing that accommodates the rotation drive unit and the compression unit in a housing space in which the refrigerant exists, and that contains lubricating oil in a storage space formed below the housing space;
A heater for heating the lubricating oil in the storage space;
A lubricating oil circulation part that supplies the lubricating oil in the storage space to at least one of the rotational sliding part and the compression sliding part in the accommodating space;
A heating region provided in the casing, covering the heater so as to be immersed in the lubricating oil dripped and stored in the storage space from the rotary sliding portion, and a heating region in which the heater exists in the lubricating oil; A cover that divides into a non-heated area outside the heated area that communicates with the heated area;
A turbo compressor comprising: The lubricating oil circulation part is
A pump provided to be immersed in the lubricating oil in the storage space, and sucking out the lubricating oil to the outside of the casing;
A lubricating oil flow path that guides the lubricating oil sucked out by the pump from the upper part of the casing to the rotary sliding part, wherein the pump is disposed in the heating region. Item 4. The turbo compressor according to Item 1. A first end side of the heating region communicates with the non-heating region;
The turbo compressor according to claim 2, wherein the pump is disposed on a second end side in the heating region. The cover has a cylindrical shape extending across the front first end and the second end;
The heater extends inside the cover along the extending direction of the cover,
4. The turbo according to claim 3, further comprising a fin that is provided on at least one of an inner peripheral surface of the cover and an outer peripheral surface of the heater and has a spiral shape extending in an extending direction of the cover and the heater. Compressor. The heater is
A heat transfer portion provided integrally with the casing so as to protrude from the inner surface of the casing;
A heater main body formed in the heat transfer portion and disposed in an insertion hole communicating with the outside of the casing;
The turbo compressor according to any one of claims 1 to 4, wherein the turbo compressor is provided.   The turbo compressor according to claim 1, wherein a hollow portion is formed inside the cover.   The turbo compressor according to any one of claims 1 to 6, wherein at least a part of the cover is a perforated plate. A turbo refrigerator comprising the turbo compressor according to any one of claims 1 to 7.

Images