WO2010092813A1

WO2010092813A1 - Scroll-type fluid machine

Info

Publication number: WO2010092813A1
Application number: PCT/JP2010/000852
Authority: WO
Inventors: 高部哲也; 大谷尚史
Original assignee: サンデン株式会社
Priority date: 2009-02-13
Filing date: 2010-02-12
Publication date: 2010-08-19
Also published as: JP2010185412A

Abstract

Disclosed is a scroll type fluid machine which can efficiently raise the heat-exchange efficiency of a refrigeration cycle through a simple and efficient lubricating oil circulation means. The machine is provided with a scroll unit (8); a frame (16), which is fixed to a sealed container (2), and which supports a drive shaft (4) such that said drive shaft (4) is rotatable, and which also supports a mobile scroll (44) such that said mobile scroll (44) may move in an orbiting fashion; a lubricating oil chamber (64) provided in the sealed container (2) at an end of the drive shaft (4), and where lubricating oil acted on by the high pressure side pressure of the working fluid accumulates; a back pressure chamber (88) formed between the frame and the back surface (44a) of the mobile scroll, and which presses the mobile scroll against a fixed scroll (46) through back pressure generated by means of lubricating oil being supplied from the lubricating oil chamber; a valve chamber (122) provided on the fixed scroll, and which is connected to the back pressure chamber; a lubricating oil circulation means (98), which has a circulation path (100) connecting the valve chamber to the lubricating oil chamber; and a valve mechanism (126) provided in the valve chamber, and which opens and closes the circulation path in response to the pressure in the back pressure chamber.

Description

Scroll type fluid machinery

The present invention relates to a scroll type fluid machine, and more particularly to a scroll type fluid machine suitable for being incorporated in a refrigeration cycle.

This type of scroll type fluid machine includes a drive shaft extending in the sealed container, a fixed scroll fixed to the sealed container, a movable scroll coupled to the drive shaft and revolved around the axis of the fixed scroll. Cooperates with each other to form an expansion chamber (working space) for refrigerant as a working fluid, discharges the refrigerant in the expansion chamber through a discharge port, and is fixed in a sealed container so that the drive shaft can rotate freely. And a frame that supports the movable scroll so as to be capable of revolving and revolving, a lubricating oil chamber that is provided in a sealed container and stores lubricating oil, and is formed between the frame and the back of the movable scroll. A back pressure chamber that presses the movable scroll against the fixed scroll by a back pressure generated by the supply of lubricating oil in the chamber, and an oil discharge portion that discharges the lubricating oil from the back pressure chamber. Scroll type expander has been known (for example, see Patent Document 1).

JP 2008-88854 A

However, in the above prior art, no special consideration is given to the lubricating oil circulation means for smoothly returning the lubricating oil for lubricating the expander to the lubricating oil chamber, and the circulating oil is circulated through the refrigeration cycle in which the scroll type fluid machine is incorporated. There is a problem that the heat exchange efficiency of the refrigeration cycle is lowered by excessively containing lubricating oil in the working fluid and flowing out into the refrigeration cycle.
Moreover, in the said prior art, there exists a possibility that an expander may become poor lubrication and may be seized by having lubricating oil contained excessively in a working fluid and flowing out into a refrigerating cycle.

On the other hand, in order to configure the lubricating oil circulation means, an oil separator for separating the lubricating oil from the refrigerant is generally required, and there is a problem that the lubricating oil circulation means and the scroll type fluid machine are enlarged and complicated. .
Further, since the lubricating oil passes through the pump mechanism, a mechanical loss of the whole system of the lubricating oil circulating means occurs, and there is a problem that the fluid machine cannot be operated properly and efficiently.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a scroll type fluid machine that can improve the heat exchange efficiency of the refrigeration cycle by a simple and highly efficient lubricating oil circulation means. .

In order to achieve the above object, a scroll type fluid machine according to a first aspect of the present invention includes a drive shaft extending through the sealed container, a fixed scroll fixed to the sealed container, and one end of the drive shaft coupled to each other. A movable scroll that revolves around the core forms a working space for the working fluid in cooperation with each other. The scroll unit discharges the working fluid in the working space through the discharge port, and is fixed to the sealed container and driven. A frame that rotatably supports the shaft and supports the movable scroll so as to be capable of revolving, and a lubricating oil that is provided on the other end side of the drive shaft in the hermetic container and that acts on the high pressure side pressure of the working fluid is stored. It is formed between the lubricating oil chamber and the frame and the back of the movable scroll, and the movable scroll is fixed to the fixed scroll by the back pressure generated when the lubricating oil in the lubricating oil chamber is supplied. Provided in the fixed scroll, a valve chamber communicating with the back pressure chamber, a lubricating oil circulation means having a circulation path communicating between the valve chamber and the lubricating oil chamber, and provided in the valve chamber, And a valve mechanism that opens and closes the circulation path according to the pressure in the back pressure chamber.

According to a second aspect of the present invention, in the first aspect, the fixed scroll is formed on a sliding surface of the fixed scroll on which the movable scroll is slid in accordance with the revolving orbiting motion of the movable scroll, and the central portion of the fixed scroll is formed. The valve chamber is communicated with the back pressure chamber through the annular groove.
Furthermore, in the invention of claim 3, in claim 2, the lubricating oil circulation means is inserted in the circulation path and temporarily stores the lubricating oil passing through the valve chamber, and the lubricating oil stored in the oil chamber And a pressure raising means for raising the pressure to the high pressure side pressure of the working fluid and delivering the pressure to the lubricating oil chamber side.

Furthermore, in the invention of claim 4, in claim 3, the oil chamber is provided with a high-pressure supply path for introducing the high-pressure side pressure of the working fluid, and the boosting means communicates the high-pressure supply path with the oil chamber. The lubricating oil stored in is increased to the high pressure side pressure of the working fluid.
According to a fifth aspect of the present invention, in the third aspect of the present invention, the pump includes a pump inserted in a circulation path between the oil chamber and the lubricating oil chamber, and the boosting means is stored in the oil chamber by driving the pump. It is characterized in that the lubricating oil is increased to the high pressure side pressure of the working fluid.

Furthermore, in the invention of claim 6, in any one of claims 3 to 5, it comprises first oil level detection means for detecting the oil level of the lubricating oil stored in the oil chamber. When the oil level of the lubricating oil detected by the surface level detecting means is equal to or higher than a predetermined oil level, the lubricating oil stored in the oil chamber is increased to the high pressure side pressure of the working fluid.

Furthermore, in the invention of claim 7, in any one of claims 3 to 6, there is provided a second oil level detecting means for detecting the oil level of the lubricating oil stored in the lubricating oil chamber. When the lubricating oil level detected by the second oil level detecting means is less than a predetermined oil level, the lubricating oil stored in the oil chamber is increased to the high pressure side pressure of the working fluid. It is characterized by.

The invention according to claim 8 is the invention according to any one of claims 3 to 5, further comprising oil recovery time detection means for detecting the recovery time of the lubricating oil recovered in the oil chamber, wherein the boosting means is the oil recovery time detection means. When the recovery time of the lubricating oil detected at is equal to or longer than a predetermined recovery time, the lubricating oil stored in the oil chamber is raised to the high pressure side pressure of the working fluid.
Furthermore, the invention of claim 9 is characterized in that, in any of claims 3 to 8, the oil chamber is provided in a sealed container.

Furthermore, in the invention of claim 10, in any one of claims 1 to 9, the drive shaft is disposed in the vertical direction in the vertical direction and connected to the upper end side of the drive shaft, and the lower end of the drive shaft. The scroll-type fluid machine of the vertical type comprising a compressor connected to the side, wherein the scroll unit is an expander, and the lubricating oil chamber stores lubricating oil for lubricating the expander and the compressor. It is characterized by being.

According to an eleventh aspect of the present invention, in any one of the first to ninth aspects, the drive shaft has a longitudinal direction arranged in a vertical direction and is connected to an upper end side of the drive shaft, and a lower end side of the drive shaft. A scroll-type fluid machine of a vertical type comprising a compressor connected to the compressor, wherein the scroll unit is an expander and prevents rotation of the drive shaft between the expander side and the compressor side in the sealed container. A partition wall is provided, and the lubricating oil chamber is formed on the upper side of the partition wall and stores lubricating oil for lubricating the expander.

According to the scroll type fluid machine of the present invention of claim 1, provided in the fixed scroll is a valve chamber communicating with the back pressure chamber, and a lubricating oil circulation means having a circulation path communicating the valve chamber and the lubricating oil chamber. And a valve mechanism that opens and closes the circulation path according to the pressure in the back pressure chamber. As a result, the lubricating oil in the back pressure chamber is recovered in the lubricating oil chamber according to the pressure in the back pressure chamber independently of the working fluid discharged through the discharge port of the scroll unit, and is supplied to the back pressure chamber again. can do. Therefore, it is possible to prevent the lubricating oil from being excessively contained in the working fluid and flowing out into the refrigeration cycle in which the scroll type fluid machine is incorporated without using an oil separator or the like, and simplify the heat exchange efficiency of the refrigeration cycle. Can be improved.
According to the second aspect of the present invention, the fixed scroll is formed on the sliding surface of the fixed scroll on which the movable scroll is slid along with the revolving turning motion of the movable scroll, and the center of the fixed scroll is the center. The valve chamber is communicated with the back pressure chamber via the annular groove. As a result, the lubricating oil supplied from the back pressure chamber to the sliding surface along with the revolving orbiting motion of the movable scroll can be efficiently recovered by receiving it once in the annular groove, so that the heat exchange efficiency of the refrigeration cycle Can be further improved.

Furthermore, according to the invention of claim 3, the lubricating oil circulation means is inserted in the circulation path and temporarily stores the lubricating oil that has passed through the valve chamber, and the lubricating oil stored in the oil chamber is used as the working fluid. Pressure increasing means for increasing the pressure to the high pressure side pressure and sending the pressure to the lubricating oil chamber side. As a result, the lubricating oil stored in the oil chamber can be substantially equalized with the lubricating oil chamber where the high-pressure side pressure of the working fluid acts, so that the lubricating oil can be more smoothly collected in the lubricating oil chamber. The heat exchange efficiency of the refrigeration cycle can be further improved.

Furthermore, according to the invention of claim 4, the oil chamber is provided with a high-pressure supply path for introducing the high-pressure side pressure of the working fluid, and the boosting means is stored in the oil chamber by communicating the high-pressure supply path with the oil chamber. The pressure of the lubricating oil is increased to the high pressure side pressure of the working fluid. Accordingly, the pressure of the lubricating oil can be increased using the high-pressure side pressure of the working fluid, so that the lubricating oil circulation means can be configured more simply.

According to a fifth aspect of the present invention, the pump includes a pump inserted in the circulation path between the oil chamber and the lubricating oil chamber, and the boosting means supplies the lubricating oil stored in the oil chamber by driving the pump. Increase the pressure to the high pressure side of the working fluid. Thereby, since it is possible to reliably raise the pressure of the lubricating oil without depending on the fluctuation of the high pressure side pressure of the working fluid, it is possible to reliably improve the heat exchange efficiency of the refrigeration cycle.

Further, according to the inventions of

claims

6 and 8, the boosting means is configured such that when the oil level of the lubricating oil detected by the oil level detecting means is equal to or higher than a predetermined oil level (invention 6), or When the lubricant recovery time detected by the oil recovery time detection means is equal to or longer than a predetermined recovery time (Claim 8), the lubricant stored in the oil chamber is increased to the high pressure of the working fluid. As a result, the pressure can be raised after a predetermined amount of lubricating oil is stored in the oil chamber, so that the lubricating oil can be collected more smoothly into the lubricating oil chamber, and the heat exchange efficiency of the refrigeration cycle can be further improved. Can do.

Furthermore, according to the invention of claim 7, the second oil level detecting means for detecting the oil level of the lubricating oil stored in the lubricating oil chamber is provided, and the boosting means has the second oil level detecting. When the oil level detected by the means becomes less than a predetermined oil level, the lubricating oil stored in the oil chamber is increased to the high pressure side pressure of the working fluid. As a result, the lubricating oil can be continuously supplied to the scroll unit without being interrupted, so that the hydraulic machine is appropriately and efficiently applied by applying an appropriate back pressure to the movable scroll with the supplied high-pressure lubricating oil. It can be operated.

According to the ninth aspect of the present invention, since the oil chamber is provided in the sealed container, the lubricating oil circulating means can be further simplified.
Further, according to the inventions of

claims

10 and 11, the drive shaft is arranged in the vertical direction in the longitudinal direction, and is connected to the upper end side of the drive shaft and the compressor connected to the lower end side of the drive shaft. And a scroll unit is an expander, and a lubricating oil chamber is formed on the upper side of the partition wall and stores lubricating oil for lubricating the expander and the compressor. Is done. On the other hand, in the case of including a partition wall that partitions the expander side and the compressor side in the sealed container without hindering the rotation of the drive shaft, the lubricating oil chamber is formed on the upper side of the partition wall and lubricates the expander. Lubricating oil is stored. By these, since the compressor-integrated expander can be configured, by incorporating this compressor-integrated expander into, for example, a heat pump or a refrigeration circuit, a water heater, an air conditioner, or the like on which the heat pump or refrigeration circuit is mounted The configuration can be simplified and the efficiency can be improved.

It is the longitudinal section showing the scroll type fluid machine concerning a 1st embodiment of the present invention. It is the expanded sectional view which looked at the A section of FIG. 1 from the discharge pipe side in FIG. It is the schematic diagram which showed the lubricating oil circulation circuit which concerns on 2nd Embodiment of this invention. It is the longitudinal cross-sectional view which showed the lubricating oil circulation circuit which concerns on 3rd Embodiment of this invention only by the expander side of a scroll type fluid machine. It is the schematic diagram which showed the modification of the lubricating oil circulation circuit which concerns on 1st Embodiment of this invention.

Hereinafter, an embodiment of the present invention will be described first from the first embodiment with reference to the drawings.
FIG. 1 shows a longitudinal sectional view of a scroll type fluid machine 1 according to the present embodiment.
As shown in FIG. 1, the fluid machine 1 is a vertically-placed, for example, compressor-integrated expander, and a two-stage compression in which a later-described compressor 12 constituting the fluid machine 1 serves as a low-stage compressor. The refrigeration cycle is incorporated in a refrigeration air conditioner, a heat pump type hot water heater, or the like. In this refrigeration cycle, the expansion energy of the refrigerant is converted into motive power by an expander 8 which will be described later, and the compressor 12 is rotated. The compressor 12 drives a high-stage compressor (not shown) constituting the two-stage compressor. Assisting.

The fluid machine 1 includes a housing (sealed container) 2, and a drive shaft 4 that drives the fluid machine 1 is extended in the housing 2 with the longitudinal direction thereof being arranged in the vertical direction.
An upper eccentric shaft portion (one end portion) 6 that is eccentric from the shaft center of the drive shaft 4 is integrally formed at the upper end of the drive shaft 4, and an expander ( A scroll unit 8 is connected.

On the other hand, a lower eccentric shaft portion (lower end portion) 10 that is eccentric from the shaft center of the drive shaft 4 is integrally formed at the lower end of the drive shaft 4, and the lower eccentric shaft portion 10 is interposed via a bearing portion 11. The compressor 12 is connected. In other words, the expander 8 and the compressor 12 to which the common drive shaft 4 is connected are accommodated in the housing 2 in the vertical direction in order from the top.
The housing 2 includes a center shell 14 that forms a cylindrical body portion of the fluid machine 1, an upper frame 16 that rotatably supports the upper end side of the drive shaft 4 via a bearing portion 15, and an upper portion of the fluid machine 1. The cap-shaped top shell 18 to cover, the lower frame 20 which rotatably supports the lower end side of the drive shaft 4 via the bearing portion 19, and the cap-shaped bottom shell 22 which covers the lower part of the fluid machine 1 are configured. ing.

The housing 2 is sealed by the

shells

14, 18, 22 and the

frames

16, 20, and the pressure of the refrigerant as the working fluid of the fluid machine 1 taken in from the external circuit is applied to the inside of the housing 2.
Specifically, the top shell 18 is connected to a suction pipe 24 that sucks the refrigerant taken in from an external circuit, and a suction chamber 26 in which the suction pipe 24 is opened is formed inside the top shell 18. The upper frame 16 is connected to a discharge pipe 28 that discharges the refrigerant that has passed through the suction pipe 24, the suction chamber 26, and the expander 8 to the outside of the housing 2.

On the other hand, the lower frame 20 is connected to a suction pipe 30 that sucks the refrigerant taken in from the external circuit, and the bottom shell 22 is supplied with the refrigerant sucked from the suction pipe 30 and passed through the compressor 12 to the outside of the housing 2. A discharge pipe 32 for discharging is connected, and the discharge pipe 32 is opened to a discharge chamber 34 formed inside the bottom shell 22.
The inside of the center shell 14 is partitioned by a partition wall 36 into a space 38 on the expander 8 side and a space 40 on the compressor 12 side, and a mechanical seal 42 is mounted at a position where the partition shaft 36 penetrates the drive shaft 4. 42 hermetically seals the space 38 and the space 40 without hindering driving of the drive shaft 4.

The expander 8 includes a movable scroll 44 and a fixed scroll 46, and spiral wraps are erected on the

scrolls

44 and 46 so as to face each other.
The movable scroll 44 is supported by the pedestal portion of the upper frame 16 so as to be capable of revolving without rotating, and a boss portion 48 is projected on the surface opposite to the standing surface of the wrap of the movable scroll 44. Are connected to the upper eccentric shaft portion 6.

The fixed scroll 46 is fixed to the upper frame 16, and a suction hole 50 opened to the suction chamber 26 is formed through the center of the fixed scroll 46. A discharge pipe 28 is connected to the outer periphery of the fixed scroll 46. A discharge chamber (discharge port) 52 is formed.
According to the expander 8 described above, the refrigerant sucked from the suction pipe 24 is taken into the expander 8 through the suction chamber 26 and the suction hole 50, and the movable and fixed

scrolls

44 and 46 cooperate with each other. It is expanded in an expansion chamber (working space) formed between the wraps of the

scrolls

44 and 46. The volume of the expansion chamber is increased while moving toward the outer peripheral side of each of the

scrolls

44 and 46, and accordingly, the movable scroll 44 is revolved around the axis of the fixed scroll 46.

The drive shaft 4 is rotationally driven in accordance with the orbiting orbiting motion of the movable scroll 44, and the refrigerant used for the orbiting orbiting motion of the movable scroll 44 and thus generating the driving force of the driving shaft 4 is discharged inside the outer periphery of the fixed scroll 46. It is sent to an external circuit outside the housing 2 via the discharge pipe 28 via the discharge chamber 52 to which the reference numeral 28 is connected.
On the other hand, the compressor 12 includes a movable scroll 54 and a fixed scroll 56, and spiral wraps are erected on the

scrolls

54 and 56 so as to face each other.

The movable scroll 54 is supported on the pedestal portion of the lower frame 20 so as to be capable of revolving without rotating, and a boss portion 58 projects from the back surface opposite to the standing surface of the wrap. The side eccentric shaft part 10 is connected.
The fixed scroll 56 is fixed to the lower frame 20, and a discharge hole 60 opened to the discharge chamber 34 is formed through the center of the fixed scroll 56, and the suction pipe 30 is connected to the outer periphery of the fixed scroll 56. A suction chamber 62 is formed.

According to the compressor 12 described above, the refrigerant sucked from the suction pipe 30 is taken into the compressor 12 through the suction chamber 62, and the movable and fixed

scrolls

54 and 56 cooperate with each other so that the

scrolls

54 and 56. Compressed in a compression chamber formed between the laps. The volume of the compression chamber is increased while the movable scroll 54 revolves around the axis of the fixed scroll 56 by the rotation of the drive shaft 4 via the boss portion 58 and moves toward the center of each

scroll

54, 56. Will be reduced.

Then, the refrigerant whose pressure has been increased with the decrease in the volume of the compression chamber passes through the discharge hole 60 and the discharge chamber 34 and is sent to the external circuit outside the housing 2 through the discharge pipe 32.
On the other hand, in the upper and

lower spaces

38 and 40 of the partition wall 36, the upper lubricating oil chamber in which lubricating oil for lubricating the

scrolls

44 and 46 of the expander 8 and the

scrolls

54 and 56 of the compressor 12 is stored, respectively. (Lubricating oil chamber) 64 and a lower lubricating oil chamber 66 are formed.

Specifically, in the drive shaft 4,

oil passages

68 and 70 that open to the upper end and the lower end thereof are drilled along the axial direction of the drive shaft 4, and the

oil passages

68 and 70 are respectively in the radial direction of the drive shaft 4. Are connected to the respective

lubricating oil chambers

64 and 66 by oil supply holes 72 and 74 drilled along the lines.
The lubricating oil stored in the lower lubricating oil chamber 66 is discharged from the lower end of the drive shaft 4 through the oil supply hole 74 and the oil passage 70 and fills the accommodating portion 82 of the boss portion 58 of the lower frame 20. The lubricating oil filled in the accommodating portion 82 is supplied to the sliding surface 86 of the movable scroll 54 with respect to the fixed scroll 56 through the space 84 outside the movable scroll 54 and contributes to lubrication between the

scrolls

54 and 56.

On the other hand, the lubricating oil stored in the upper lubricating oil chamber 64 is discharged from the upper end of the drive shaft 4 through the oil supply hole 72 and the oil passage 68 and fills the accommodating portion 76 of the boss portion 48 of the upper frame 16. The lubricating oil filled in the housing portion 76 flows down to the upper lubricating oil chamber 64 along the drive shaft 4 while lubricating the bearing portion 15, while passing through the space 78 outside the movable scroll 44 to the fixed scroll 46. It is supplied to the sliding surface 80 of the movable scroll 44 and contributes to lubrication between the

scrolls

44 and 46.

Here, in the expander 8, a back pressure chamber 88 of the movable scroll 44 is formed between the upper frame 16 and the back surface 44 a of the movable scroll 44, and the back pressure chamber 88 is the lubricating oil in the upper lubricating oil chamber 64. The movable scroll 44 is pressed against the fixed scroll 46 by the back pressure generated by the supply of.
The back pressure chamber 88 is partitioned by an annular seal ring member 89 centering on the center of the movable scroll 44, and the low pressure side pressure of the refrigerant acting on the discharge chamber 52 by the seal ring member 89 or a back pressure adjusting mechanism (not shown). The back pressure is set to a higher pressure than the high pressure side pressure of the refrigerant acting on the suction chamber 26 or to an intermediate pressure that is slightly lower than the high pressure side pressure of the refrigerant. The lubricating oil is delivered to the outer space 78. A similar back pressure chamber 90 is also formed in the compressor 12.

In the compressor 12, the lubricating oil that has passed through the space 84 from the back pressure chamber 90 moves toward the center of the

scrolls

54 and 56 that form the compression chamber by the rotational force obtained from the expander 8 through the suction chamber 62. While being discharged from the discharge pipe 32 through the discharge hole 60 together with the refrigerant.
The refrigerant sent from the discharge pipe 32 is separated from the lubricating oil contained in the refrigerant by an oil separator (not shown) provided outside the fluid machine 1, and the separated lubricating oil is separated from the partition wall 36 of the center shell 14. Also, it is supplied from the lubricating oil supply pipe 92 connected to the lower side to the lower lubricating oil chamber 66, and again contributes to the lubrication of each sliding portion described above.

On the other hand, in the expander 8, the lubricating oil that has passed through the space 78 from the back pressure chamber 88 moves toward the outer peripheral side of each

scroll

44, 46 due to the back pressure, and is collected independently with little mixing with the refrigerant. Is done.
Specifically, in addition to the refrigerant discharge pipe 28, a lubricating oil recovery pipe 94 is connected inside the outer periphery of the fixed scroll 46, while a lubricating oil supply pipe 96 is connected above the partition wall 36 of the center shell 14. These

pipes

94 and 96 are connected to a lubricating oil circulation circuit (lubricating oil circulation means) 98.

In the lubricating oil circulation circuit 98, a three-way valve 102, an oil chamber 104, and a check valve 106 are inserted into a circulating oil pipe (circulation path) 100 to which the

pipes

94 and 96 are connected in order from the flow direction of the lubricating oil. It is configured.
The three-way valve 102 is introduced with the high-pressure side pressure of the refrigerant circulating in the refrigeration cycle in which the fluid machine 1 is incorporated, that is, the discharge pressure of a high-stage side compressor (not shown) or the pressure immediately before flowing into the expander 8. A high-pressure pipe (high-pressure supply path) 108 is connected.

The three-way valve 102 is electrically connected to a control device 110 that controls the operation of the fluid machine 1 and thus the refrigeration cycle.
The oil chamber 104 temporarily stores the lubricating oil that has passed through the three-way valve 102 and sends it to the check valve 106 side. Further, the oil chamber 104 is equipped with a level sensor (first oil level detecting means) 112 for detecting the oil level of the lubricating oil stored in the oil chamber 104, and the level sensor 112 is electrically connected to the control device 110. Connected.

Further, a pressure equalizing pipe 113 is connected to the oil chamber 104, and the pressure equalizing pipe 113 releases the pressure in the oil chamber 104, thereby reducing the pressure on the low pressure side in the refrigeration cycle so that the lubricating oil flows smoothly into the oil chamber 104. For example, it is connected to the discharge pipe 28 or the like, and is appropriately communicated by a valve (not shown).
The check valve 106 is a mechanical on-off valve that prevents backflow of the lubricating oil from the lubricating oil supply pipe 96 to the oil chamber 104.

2 is an enlarged cross-sectional view of the portion A in FIG. 1 as viewed from the discharge pipe 28 side in FIG.
As shown in FIG. 2, the sliding surface 114 of the fixed scroll 46 with respect to the movable scroll 44 (OK at 114) has an annular shape centered on the center of the fixed scroll 46 at a position facing the space 78. An annular groove 116 is formed.
A valve chamber 118 penetrating the fixed scroll 46 is formed in the annular groove 116, and the valve chamber 118 is formed with an oil passage 120 formed on the side opened to the annular groove 116, and the diameter thereof is increased from the oil passage 120. The valve accommodating part 122 and the oil path 124 which connects the valve accommodating part 122 and the lubricating oil recovery pipe | tube 94 are comprised.

A valve seat 122 a is formed on the inner surface of the valve housing portion 122 by expanding the diameter from the oil passage 120. In addition, the valve accommodating portion 122 accommodates a valve mechanism 126. The valve mechanism 126 includes a ball member 126a made of a steel ball or the like, a spring member 126b that presses the ball member 126a against the valve seat portion 122a, and a spring member 126b. It is comprised from the spring pressing member 126c to support.

The spring holding member 126c is fixed to the inside of the valve housing portion 122, and the ball 126a is pressed against the valve seat portion 122a by a predetermined elastic force of the spring member 126b, and the oil passage 120 side, the oil passage 122 side, Is hermetically sealed.
On the other hand, when the pressure in the back pressure chamber 88 rises against a predetermined elastic force of the spring member 126b, the ball member 126a is lifted away from the valve seat 122a, and the oil passage 120 side and the oil passage 124 side are lifted. And communicated with each other.

Here, the spring member 126b does not lift the ball member 126a away from the valve seat portion 122a depending on the low pressure side pressure of the refrigerant acting on the discharge chamber 52, and the low pressure side pressure of the refrigerant acting on the back pressure chamber 88. The ball member 126a is formed by a member having a predetermined elastic force that lifts the ball member 126a away from the valve seat portion 122a when the pressure is equal to or higher than the intermediate pressure between the pressure and the high pressure side pressure.
In the lubricating oil circulation circuit 98 configured as described above, the valve chamber 118 and the back pressure chamber 88 are communicated with each other via the annular groove 116, and the valve chamber 118 and the upper lubricating oil chamber 64 are disposed via the circulating oil pipe 100. The valve mechanism 126 opens and closes the circulating oil pipe 100 in accordance with the pressure in the back pressure chamber 88 to recover the lubricating oil that changes from a predetermined low pressure to an intermediate pressure.

In addition, in the control device 110, valve drive control of the three-way valve 102 is executed in order to smoothly return the lubricating oil to the upper lubricating oil chamber 64 by the lubricating oil circulation circuit 98.
Specifically, in the valve drive control, the valve body of the three-way valve 102 is switched to a direction in which only the circulating oil pipe 100 is communicated, and is first detected by the level sensor 112 in a state where the lubricating oil is being collected. It is determined whether or not the oil level of the lubricating oil in the oil chamber 104 is equal to or higher than a predetermined oil level.

Next, when it is determined that the oil level is equal to or higher than the predetermined oil level, the high pressure pipe 108 is connected to the oil chamber by switching the valve body of the three-way valve 102 from the circulating oil pipe 100 side to the high pressure pipe 108 side. The high pressure side pressure is supplied to the oil chamber 104.
The lubricating oil whose pressure has been increased to a predetermined high pressure by the high pressure side of the refrigerant passes through the check valve 106 and is smoothly returned to the upper lubricating oil chamber 64 where the high pressure side pressure of the refrigerant acts (pressure increasing means). .

As described above, in the first embodiment, by providing the valve mechanism 126 and the lubricating oil circulation circuit 98, the lubricating oil in the back pressure chamber 88 is independent of the refrigerant discharged through the discharge pipe 28 of the expander 8. Then, it can be recovered in the upper lubricating oil chamber 64 according to the pressure in the back pressure chamber 88 and supplied to the back pressure chamber 88 again. Therefore, without using an oil separator or the like, it is possible to prevent the lubricating oil from being excessively contained in the refrigerant and flowing out into the refrigeration cycle in which the fluid machine 1 is incorporated, thereby simplifying the heat exchange efficiency of the refrigeration cycle. Can be improved.

Further, by performing the valve drive control, the lubricating oil stored in the oil chamber 104 can be approximately equalized with the upper lubricating oil chamber 64 where the high-pressure side pressure of the refrigerant acts, so that the lubricating oil is lubricated to the upper side. The oil chamber 64 can be recovered more smoothly, and the heat exchange efficiency of the refrigeration cycle can be further improved.
Furthermore, in the valve drive control, the lubricating oil can be boosted using the high-pressure side pressure of the refrigerant in the refrigeration cycle, so that the lubricating oil circulation circuit 98 can be configured more simply.

Further, in the above valve drive control, the pressure can be increased after a predetermined amount of lubricating oil is stored in the oil chamber 104, so that the lubricating oil can be more smoothly collected in the upper lubricating oil chamber 64, and the refrigeration cycle can be recovered. The heat exchange efficiency can be further improved.

Next, a second embodiment of the present invention will be described with reference to FIG.
FIG. 3 shows a lubricating oil circulation circuit (lubricating oil circulation means) 128 having a configuration different from that of the first embodiment, and the other configuration is substantially the same as that of the first embodiment. The oil circulation circuit 128 will be described.

In the present embodiment, an inlet valve 130 and an outlet valve 132 inserted in the circulating oil pipes 100 before and after the oil chamber 104, and a pump 134 inserted in the circulating oil pipe 100 between the oil chamber 104 and the upper lubricating oil chamber 64. The lubricating oil circulation circuit 128 is provided.
The drive units of the inlet valve 130, the outlet valve 132, and the pump 134 are electrically connected to the control device 110. In the control device 110, in order to smoothly return the lubricating oil to the upper lubricating oil chamber 64, the inlet valve 130, Valve / pump drive control of the outlet valve 132 and the pump 134 is executed.

Specifically, in the valve / pump drive control, the level sensor is first opened in a state where the inlet valve 130 is opened, the outlet valve 132 is closed, the pump 134 is stopped, and the lubricating oil is collected. It is determined whether or not the oil level in the oil chamber 104 detected at 112 is greater than or equal to a predetermined oil level.
Next, when it is determined that the oil level is equal to or higher than the predetermined oil level, the inlet valve 130 is closed, the outlet valve 132 is opened, and the pump 134 is further driven, whereby the oil chamber The lubricating oil stored in 104 is increased to a predetermined high pressure that is about the high pressure side pressure of the refrigerant.

Then, the lubricating oil whose pressure has been increased to a predetermined high pressure about the high pressure side pressure of the refrigerant passes through the check valve 106 and is smoothly returned to the upper lubricating oil chamber 64 where the high pressure side pressure of the refrigerant similarly acts (pressure increasing means). ).
As described above, in the second embodiment, similarly to the first embodiment, the heat exchange efficiency of the refrigeration cycle can be improved efficiently by the simple and highly efficient lubricating oil circulation circuit 128.

In particular, in the second embodiment, the pump 134 is used as a means for boosting the lubricating oil, and the pump 134 is driven at a predetermined rotational speed at which the high pressure side pressure of the refrigerant can be obtained. Since the pressure of the lubricating oil can be reliably increased regardless of fluctuations, the heat exchange efficiency of the refrigeration cycle can be reliably improved.

Next, a third embodiment of the present invention will be described with reference to FIG.
FIG. 4 shows a lubricating oil circulation circuit (lubricating oil circulation means) 136 having a configuration different from those of the above embodiments only on the expander 8 side of the fluid machine 1.
In the present embodiment, the oil chamber 138 is provided in the vicinity of the upper lubricating oil chamber 64 in the housing 2, and the rest of the configuration is substantially the same as that of the first embodiment.
The oil chamber 138 is open to the back pressure chamber 88 in the pedestal portion of the upper frame 16 and is formed so as to penetrate toward the upper lubricating oil chamber 64 side.

A check valve 142 for preventing backflow of lubricating oil from the oil chamber 138 to the back pressure chamber 88 is inserted in the oil passage 140, and further, the bottom of the oil chamber 138 can communicate with the upper lubricating oil chamber 64. A check valve 144 is provided, and the check valve 144 prevents backflow of lubricating oil from the upper lubricating oil chamber 64 to the oil chamber 138.
The oil chamber 138 is provided in the vicinity of the center shell 14, and the high pressure pipe 108 is connected via the center shell 14.

A three-way valve 102 is inserted in the high-pressure pipe 108, and a pressure equalizing pipe 113 is connected to the other port of the three-way valve 102.
In the lubricating oil circulation circuit 136 configured as described above, the control device 110 executes valve drive control of the three-way valve 102 in order to smoothly return the lubricating oil to the upper lubricating oil chamber 64 where the high pressure side pressure of the refrigerant acts. Is done.

Specifically, in the valve drive control, the valve body of the three-way valve 102 is switched to a direction in which only the pressure equalizing pipe 113 is communicated, and is first detected by the level sensor 112 in a state where the lubricating oil is being collected. It is determined whether or not the oil level of the lubricating oil in the oil chamber 138 is equal to or higher than a predetermined oil level.
Next, when it is determined that the oil level is equal to or higher than the predetermined oil level, the high pressure pipe 108 is connected to the oil chamber by switching the valve body of the three-way valve 102 from the pressure equalizing pipe 113 side to the high pressure pipe 108 side. The oil chamber 138 is supplied with a high-pressure side pressure.

The lubricating oil whose pressure has been increased to a predetermined high pressure by the high pressure side of the refrigerant passes through the check valve 144 and is smoothly returned to the upper lubricating oil chamber 64 where the high pressure side pressure of the refrigerant similarly acts (pressure increasing means). .
As described above, in the third embodiment, similarly to the first and second embodiments, the heat exchange efficiency of the refrigeration cycle can be efficiently improved by the simple and highly efficient lubricating oil circulation circuit 136.

In particular, in the third embodiment, since the oil chamber 138 can be provided in the housing 2, the lubricating oil circulation circuit 136 can be further simplified.
Although the description of one embodiment of the present invention has been completed above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.
For example, in each of the above embodiments, the pressure of the lubricating oil is increased according to the oil level of the lubricating oil detected by the level sensor 112. However, the present invention is not limited to this. For example, when the recovery time of the lubricating oil recovered in the oil chamber is counted by the timer function of the control device 110 and the recovery time of the lubricating oil exceeds a predetermined recovery time, the oil chamber The stored lubricating oil may be boosted to a predetermined high pressure. Also in this case, as in the case of each of the above embodiments, the pressure can be increased after a predetermined amount of lubricating oil is stored in the oil chamber, so that the lubricating oil can be smoothly collected in the upper lubricating oil chamber 64. it can.

In the second embodiment, the

valves

130 and 132 may be removed, and the pressure of the lubricating oil may be controlled only by the pump 134, or a check valve (not shown) may be provided on the outlet side of the pump 134. You may make it prevent the reverse flow of the refrigerant | coolant to the pump 134. FIG.
Further, as a modification of the first embodiment, as shown in FIG. 5, a high pressure pipe 108 and a pressure equalizing pipe 113 are connected to the three-way valve 102, thereby leading directly to the oil chamber 104 via the three-way valve 102. The lubricating oil circulation circuit 98 may be configured by inserting the check valve 106, the oil chamber 104, and the check valve 106 into the circulating oil pipe 100 in order from the flow direction of the lubricating oil.

Furthermore, in each of the above embodiments, a level sensor (second oil level detecting means) (not shown) that detects the oil level of the lubricating oil stored in the upper lubricating oil chamber 64 is provided instead of the level sensor 112, When the oil level detected by the level sensor becomes lower than a predetermined oil level, the lubricating oil stored in the oil chamber may be increased to a predetermined high pressure. In this case, since the lubricating oil can be continuously supplied to the expander 8 without being interrupted, an appropriate back pressure is applied to the movable scroll 44 with the supplied high-pressure lubricating oil, so that the fluid machine 1 is It can be operated appropriately and efficiently.

Further, in each of the above embodiments, the partition wall 36 that partitions the expander 8 side and the compressor 12 side in the housing 2 is provided. However, the partition wall 36 is excluded to lubricate the expander 8 and the compressor 12. One common lubricating oil chamber for storing lubricating oil for the purpose may be formed. In this case, not only the partition wall 36 but also the mechanical seal 42 attached to the partition wall 36 is not necessary, so that the fluid machine 1 is more simplified and preferable.

Further, in each of the above embodiments, the drive side scroll unit is the expander 8 and the driven side scroll unit is the compressor 12 provided on the lower side of the expander 8, but either one of the two scroll units is used. May be a scroll unit on the driving side and the driven side, and the unit type of the expander 8 and the compressor 12 and the vertical arrangement are not limited. However, according to the present embodiment, it is possible to configure a compressor-integrated expander in which the expander 8 is driven by at least the discharge pressure of the refrigerant circulating in the external circuit and the compressor 12 is driven by this driving force. . By incorporating this compressor-integrated expander into a refrigeration cycle such as a heat pump or a refrigeration circuit, it is possible to simplify the configuration and improve the efficiency of a hot water supply device or an air conditioner mounted with the heat pump or refrigeration circuit preferable.

Even without using an oil separator, etc., it is possible to prevent the lubricating oil from being excessively contained in the working fluid and flowing out into the refrigeration cycle in which the scroll type fluid machine is incorporated, so that the heat exchange efficiency of the refrigeration cycle can be improved. The present invention can be applied to not only a compressor-integrated expander but also a scroll fluid machine.

1 Scroll type fluid machine 2 Housing (sealed container)
4 Drive shaft 8 Expander (scroll unit)
12 Compressor 16 Upper frame (frame)
36 Partition 44 Movable scroll 44a Back 46 Fixed scroll 52 Discharge chamber (discharge port)
64 Upper lubricating oil chamber (lubricating oil chamber)
88

Back pressure chamber

98, 128, 136 Lubricating oil circulation circuit (lubricating oil circulation means)
100 Circulating oil pipe (circulation path)
104,138 Oil chamber 108 High pressure pipe (high pressure supply path)
112 Level sensor (oil level detection means)
114 Sliding surface 116 Annular groove 122 Valve chamber 126 Valve mechanism 130 Inlet valve 132 Outlet valve 134 Pump

Claims

A drive shaft extending through the sealed container;
A fixed scroll fixed to the hermetic container and a movable scroll connected to one end of the drive shaft and revolved around the axis of the fixed scroll cooperate to form a working space for the working fluid. A scroll unit that discharges the working fluid in the working space through the discharge port;
A frame fixed to the hermetic container and rotatably supporting the drive shaft, and supporting the movable scroll so as to be capable of revolving and revolving;
A lubricating oil chamber that is provided on the other end side of the drive shaft in the sealed container and stores lubricating oil on which a high-pressure side pressure of the working fluid acts;
A back pressure chamber that is formed between the frame and the back surface of the movable scroll, and that presses the movable scroll against the fixed scroll by a back pressure generated by supplying the lubricating oil in the lubricating oil chamber;
A valve chamber provided in the fixed scroll and communicating with the back pressure chamber;
Lubricating oil circulating means having a circulation path communicating the valve chamber and the lubricating oil chamber;
A scroll type fluid machine comprising: a valve mechanism provided in the valve chamber and opening and closing the circulation path according to a pressure in the back pressure chamber.
The fixed scroll is formed on a sliding surface of the fixed scroll on which the movable scroll is slid in accordance with the revolving orbiting motion of the movable scroll, and has an annular ring groove centering on a central portion of the fixed scroll. Have
The scroll type fluid machine according to claim 1, wherein the valve chamber communicates with the back pressure chamber via the annular groove.
The lubricating oil circulation means is inserted in the circulation path and temporarily stores the lubricating oil that has passed through the valve chamber, and the lubricating oil stored in the oil chamber is supplied to the high pressure side pressure of the working fluid. 3. A scroll type fluid machine according to claim 2, further comprising pressure increasing means for increasing the pressure and sending the pressure to the lubricating oil chamber side.
A high pressure supply path for guiding the high pressure side pressure of the working fluid to the oil chamber;
4. The scroll type according to claim 3, wherein the boosting means boosts the lubricating oil stored in the oil chamber to the high-pressure side pressure of the working fluid by communicating the high-pressure supply path with the oil chamber. Fluid machinery.
A pump inserted in the circulation path between the oil chamber and the lubricating oil chamber,
4. The scroll type fluid machine according to claim 3, wherein the boosting means boosts the lubricating oil stored in the oil chamber to the high pressure side pressure of the working fluid by driving the pump.
A first oil level detecting means for detecting an oil level of lubricating oil stored in the oil chamber;
When the oil level detected by the first oil level detecting unit is equal to or higher than a predetermined oil level, the boosting unit removes the lubricating oil stored in the oil chamber from the working fluid. 6. The scroll type fluid machine according to claim 3, wherein the pressure is increased to the high pressure side pressure.
A second oil level detecting means for detecting an oil level of the lubricating oil stored in the lubricating oil chamber;
When the oil level of the lubricating oil detected by the second oil level detecting means is less than a predetermined oil level, the boosting means removes the lubricating oil stored in the oil chamber from the working fluid. 7. The scroll type fluid machine according to claim 3, wherein the pressure is increased to the high pressure side pressure.
Oil recovery time detection means for detecting the recovery time of the lubricating oil recovered in the oil chamber,
The pressurizing means is configured to reduce the lubricating oil stored in the oil chamber to the high-pressure side pressure of the working fluid when the lubricating oil recovery time detected by the oil recovery time detecting means is equal to or longer than a predetermined recovery time. 6. The scroll type fluid machine according to claim 3, wherein the pressure is increased.
The scroll type fluid machine according to any one of claims 3 to 8, wherein the oil chamber is provided in the sealed container.
The drive shaft has a vertical scroll type fluid, the longitudinal direction of which is arranged in the vertical direction, and includes an expander connected to the upper end side of the drive shaft and a compressor connected to the lower end side of the drive shaft. A machine,
The scroll unit is an expander,
The scroll type fluid machine according to any one of claims 1 to 9, wherein the lubricating oil chamber stores lubricating oil for lubricating the expander and the compressor.
The drive shaft has a vertical scroll type fluid, the longitudinal direction of which is arranged in the vertical direction, and includes an expander connected to the upper end side of the drive shaft and a compressor connected to the lower end side of the drive shaft. A machine,
The scroll unit is an expander,
A partition that partitions the expander side and the compressor side in the sealed container without interfering with the rotation of the drive shaft;
The scroll type fluid machine according to any one of claims 1 to 9, wherein the lubricating oil chamber is formed above the partition wall and stores lubricating oil for lubricating the expander.