JP5270993B2 - Scroll type fluid machinery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scroll fluid machine capable of reducing power loss in a scroll unit and thereby improving its efficiency by reducing sliding friction resistance of a movable scroll to an end plate surface of a fixed scroll. <P>SOLUTION: The scroll fluid machine includes an outer peripheral space (44) which is formed on an outer peripheral side of the movable scroll (22) and is supplied with lubrication oil of lower pressure than that of a compression chamber, a sliding surface (46) which is formed on the end plate surface (28a) of the fixed scroll (24) and is supplied with the lubrication oil from the outer peripheral space and on which the movable scroll slides along with its orbital rotating movement, and a lubrication oil supply groove (50) formed in the sliding surface, which the movable scroll intermittently strides along with the orbital rotating movement of the movable scroll. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  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 air conditioner or a heat pump type water heater.

  A scroll type fluid machine of this type, for example, a hermetic scroll compressor, includes a scroll unit composed of a fixed scroll and a movable scroll each having a spiral wrap paired on each end plate surface of each end plate and fixed. The orbiting scroll revolves with respect to the scroll to form a compression chamber for the working fluid between these laps, and the compression chamber moves toward the center in the radial direction of each end plate while reducing its volume. Further, an outer peripheral space to which lubricating oil having a pressure lower than that of the compression chamber is supplied is formed on the outer peripheral side of the movable scroll.

And the scroll compressor which provided the oil supply groove | channel of the lubricating oil from outer peripheral space in the end plate surface of a fixed scroll is disclosed (for example, refer patent document 1, 2).
JP 2004-293533 A JP 2007-303318 A

  However, in each of the above prior arts, the lubricating oil cannot be positively supplied to the oil supply groove and thus to the sliding surface, which may lead to a shortage of lubricating oil on the sliding surface particularly when the compressor rotates at a high speed. Due to the lack of lubricating oil on the sliding surface, there is a problem that the sliding friction resistance of the movable scroll with respect to the end plate surface of the fixed scroll, and consequently the power loss in the scroll unit, increases, and the compression efficiency of the compressor decreases.

  The present invention has been made in view of such a problem, and reduces the sliding frictional resistance of the movable scroll with respect to the end plate surface of the fixed scroll, thereby reducing the power loss in the scroll unit and thus improving the efficiency thereof. It is an object of the present invention to provide a scroll type fluid machine capable of performing the above.

In order to achieve the above object, the scroll type fluid machine according to claim 1 is composed of a fixed scroll and a movable scroll in which spiral wraps are erected in pairs on each end plate surface of each end plate. A scroll unit in which a working fluid compression chamber is formed between the laps by a revolving orbiting movement of the movable scroll with respect to the scroll, and the compression chamber moves toward the radial center of each end plate while reducing its volume. And an outer peripheral space formed on the outer peripheral side of the movable scroll and supplied with lubricating oil at a pressure lower than that of the compression chamber, and formed on the end plate surface of the fixed scroll, and supplied with the lubricating oil from the outer peripheral space, and the movable scroll Is a sliding surface that slides along with the revolution orbiting motion, and a lubricant that is formed on the sliding surface and that the movable scroll straddles intermittently with the revolution orbiting motion of the movable scroll. And a oil supply groove, the oil supply groove, when the movable scroll crosses intermittently, one end of the oil supply groove, and the other end portion is formed in a range exposed sequentially as viewed from the movable scroll-side, orbital direction of the movable scroll It is characterized by extending along .

Also, in the invention described in claim 2, in claim 1, the end plate surface of the fixed scroll, the outer peripheral side of the movable scroll than the oil supply groove, the circumferential groove for adjusting the pressure in the outer peripheral space is formed The one end and the other end communicate with the circumferential groove.

Therefore, according to the scroll type fluid machine of the first aspect of the present invention, the lubricating oil supply groove is formed on the sliding surface so that the movable scroll intermittently strides with the revolving turning motion of the movable scroll. Thereby, since lubricating oil can be intermittently sent from the outer peripheral space to the oil supply groove and the lubricating oil can be positively supplied to the sliding surface, the lubricity on the sliding surface is improved.
Further, since the area of the sliding surface is reduced with the formation of the oil supply groove on the sliding surface, it is possible to reduce the sliding frictional resistance of the movable scroll with respect to the end plate surface of the fixed scroll. Therefore, power loss in the scroll unit can be reduced, and as a result, the efficiency of the scroll type fluid machine can be improved.

Further, according to the present invention, the oil supply groove is formed in a range in which one end portion and the other end portion of the oil supply groove are sequentially exposed when viewed from the movable scroll side when the movable scroll straddles intermittently. As a result, the lubricating oil sent from one end to the oil supply groove is sequentially sent out of the oil supply groove from the other end along with the revolving turning motion of the movable scroll, and the flow of the lubricating oil in the oil supply groove can be promoted. it can. Therefore, the lubricity on the sliding surface is improved, and the lubricating oil itself staying in the oil supply groove can be prevented from becoming a sliding frictional resistance of the movable scroll, so that the power loss in the scroll unit can be further reduced. The efficiency of the scroll type fluid machine can be further improved.

Furthermore, according to the present invention, the oil supply groove extends along the revolution turning direction of the movable scroll. As a result, the flow of the lubricating oil in the oil supply groove can be further promoted along with the revolving turning motion of the movable scroll, so that the power loss in the scroll unit can be further reduced, and the efficiency of the scroll type fluid machine is further improved. Can be improved.

Also, according to the second aspect of the present invention, in the sliding surface, on the outer peripheral side of the movable scroll than the oil supply groove, the circumferential groove for adjusting the pressure in the outer peripheral space is formed, one end portion and the other The end communicates with the circumferential groove. As a result, the flow of the lubricating oil in the oil supply groove can be further promoted by using the circumferential groove along with the revolving turning motion of the movable scroll, so that the power loss in the scroll unit can be further reduced. The efficiency of the scroll type fluid machine can be further improved.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a longitudinal sectional view of a hermetic scroll compressor as an example of a scroll type fluid machine according to the present embodiment.
The compressor 1 is incorporated in a refrigeration circuit such as a refrigeration air conditioner or a heat pump water heater, and the circuit includes a path through which a carbon dioxide refrigerant (hereinafter referred to as a refrigerant), which is an example of a working fluid, circulates. Sucks refrigerant from the path, compresses it, and discharges it toward the path.

  The compressor 1 includes a shell 2, and a center shell 4 that forms a cylindrical body of the shell 2 is hermetically fitted with an upper side and a lower side by a top shell 6 and a bottom shell 8, respectively, and the inside of the center shell 4 is hermetically sealed. The discharge pressure of the refrigerant is acting. A suction pipe 10 for sucking the refrigerant taken in from the circuit is connected to the refrigerant suction chamber formed in the center shell 4, and the compressed refrigerant in the shell 2 is sent to the circuit at an appropriate position of the top shell 6. A discharge pipe 12 is connected.

In the center shell 4, a scroll unit 14, an electric motor 16, and a pump unit 18 are accommodated in this order from above, and a rotating shaft 20 is disposed in the electric motor 16, and the rotating shaft 20 is energized by energization of the electric motor 16. Driven by rotation.
The rotary shaft 20 has an upper end connected to the scroll unit 14 and a lower end connected to the pump unit 18, and the rotary shaft 20 is driven to rotate by the electric motor 16, whereby the scroll unit 14 sucks and compresses the refrigerant. And a series of discharge processes.

  Specifically, the scroll unit 14 includes a movable scroll 22 and a fixed scroll 24, and the movable scroll 22 includes an end plate 26. A spiral wrap extending toward the end plate 28 of the fixed scroll 24 is provided on the end plate surface 26 a of the end plate 26. On the other hand, a spiral wrap 32 extending toward the end plate 26 is also set up on the end plate surface 28 a of the end plate 28 of the fixed scroll 24.

These wraps 30 and 32 are formed on the basis of a predetermined involute curve, and they are arranged in pairs and cooperate with each other, so that the refrigerant is sucked through the suction pipe 10 and the wraps 30 and 32 are separated. And a refrigerant compression chamber is formed.
The suction chamber is formed on the end plate 28 of the fixed scroll 24, and the suction pressure of the refrigerant acts on the suction chamber. On the other hand, the compression chamber is rotated by the revolving orbiting motion of the movable scroll 22 with respect to the fixed scroll 24. Move toward the side, decreasing its volume.

In order to give the orbiting scroll 22 a revolving orbiting motion, a boss 34 is formed on the back surface 26b side of the end plate 26, and the boss 34 is rotatable about an eccentric shaft 36 integrally formed on the upper end side of the rotary shaft 20 via a bearing. It is supported by. The rotation of the movable scroll 22 is blocked by a rotation blocking pin (not shown).
On the other hand, the fixed scroll 24 is supported and fixed to the main frame 38 fixed to the inside of the center shell 4, and a discharge hole 40 that can communicate with the compression chamber is formed in the central portion of the fixed scroll 24. Yes.

On the other hand, the pump unit 18 sucks the lubricating oil stored inside the bottom shell 8, and the sucked lubricating oil passes through an oil passage 42 drilled in the rotating shaft 20 from the upper end of the rotating shaft 20. And is supplied to the scroll unit 14 and the like, and contributes to the lubrication of each sliding portion and bearing, and the sealing and lubrication of the sliding surface.
Specifically, the lubricating oil that has passed through the oil passage 42 flows down from the upper end of the rotating shaft 20 to the electric motor 16 side along the rotating shaft 20, while between the back surface 26 b of the end plate 26 of the movable scroll 22 and the main frame 38. Lubricating oil, which is supplied to the formed back pressure chamber and passes through the outer peripheral space 44 between the outer peripheral surface of the end plate 26 and the main frame 38 from the back pressure chamber, moves the movable scroll 22 of the end plate surface 28 a to the fixed scroll 24. It is supplied to a sliding surface 46 which is a sliding area.

  Here, the discharge pressure of the coolant of the lubricating oil is applied to the back pressure chamber via the oil passage 46 located at the radial center of the end plates 26 and 28 by an annular seal ring 48 fixed to the main frame 38. The high pressure chamber is divided into an intermediate pressure chamber located on the radially outer peripheral side of the end plates 26 and 28 and depressurized from the high pressure chamber. By forming such a back pressure structure, the movable scroll 22 is appropriately pressed against the fixed scroll 24 mainly by the pressure of the intermediate pressure chamber, and the smooth revolving motion of the movable scroll 22 is realized.

  According to the compressor 1 described above, the orbiting scroll 22 revolves without rotating as the rotary shaft 20 rotates, so that the refrigerant sucked into the scroll unit 14 via the suction pipe 10 passes through the compression chamber. Then, the refrigerant in the compression chamber is compressed while being moved toward the center of the scroll unit 14, and then discharged into the shell 2 through the discharge hole 40, circulated through the shell 2, and then the compressor 1 through the discharge pipe 12. Sent out.

By the way, in this embodiment, the lubrication oil supply groove | channel 50 which the movable scroll 22 straddles intermittently with the revolving turning motion of the movable scroll 22 is formed in the sliding surface 46. As shown in FIG.
Specifically, as shown in the plan view of the fixed scroll 24 of FIG. 2 as viewed from the sliding surface 46 side, the oil supply groove 50 has a sliding area of the movable scroll 22 on the sliding surface 46 and a sliding surface of the movable scroll 22. In the region A where the moving time is relatively larger than the other regions of the sliding surface 46, an arc-shaped long groove having a width of about 2 mm and a depth of about 1 mm is formed.

Moreover, as shown in the plan view of the scroll unit 14 for each revolution turning angle of the movable scroll 22 in FIGS. 3 and 4, the oil supply groove 50 has one end portion of the oil supply groove 50 when the movable scroll 22 straddles intermittently. 50a and the other end 50b are extended along the revolution turning direction of the movable scroll 22 in a range where the movable scroll 22 is sequentially exposed when viewed from the movable scroll 22 side.
As described above, in the present embodiment, the lubrication oil supply groove 50 that the movable scroll 22 straddles intermittently with the revolving turning motion of the movable scroll 22 is formed on the sliding surface 46, thereby supplying oil from the outer peripheral space 44. Since the lubricating oil can be intermittently fed into the groove 50 and actively supplied to the sliding surface 46, the lubricity on the sliding surface 46 is improved.

Further, since the area of the sliding surface 46 decreases with the formation of the oil supply groove 50 on the sliding surface 46, the sliding friction resistance of the movable scroll 22 with respect to the end plate surface 28a of the fixed scroll 24 can be reduced. .
Moreover, since the oil supply groove 50 is formed in a range where the one end 50a and the other end 50b of the oil supply groove 50 are sequentially exposed when viewed from the side of the movable scroll 22 when the movable scroll 22 straddles intermittently. The lubricating oil fed into the oil supply groove 50 from the one end portion 50a is sequentially sent out of the oil supply groove 50 from the other end portion 50b along with the revolving and turning motion of 22 to promote the flow of the lubricating oil in the oil supply groove 50. Can do. Therefore, the lubricity on the sliding surface 46 is improved and the lubricating oil itself staying in the oil supply groove 50 can be prevented from becoming a sliding frictional resistance of the movable scroll 22.

  Furthermore, since the oil supply groove 50 extends in an arc shape along the revolution turning direction of the movable scroll 22, the flow of lubricating oil in the oil supply groove 50 is further promoted along with the revolution turning movement of the movable scroll 22. Therefore, the power loss in the scroll unit 14 can be greatly reduced, and as a result, the compression efficiency of the compressor 1 can be greatly improved.

The description of one embodiment of the present invention is finished above, but the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, as shown in the plan view of the fixed scroll 24 in FIG.
On the end plate surface 28 a of the fixed scroll 24, a circumferential groove 52 for adjusting the pressure of the outer peripheral space 44 to the outer peripheral side of the movable scroll 22 from the oil supply groove 50 via a back pressure adjusting valve (not shown) of the back pressure chamber. Is formed. The circumferential groove 52 has substantially the same width and depth as the oil supply groove 50, and the one end portion 50 a and the other end portion 50 b are formed up to a range communicating with the circumferential groove 52.
As shown in the plan view of the scroll unit 14 for each revolution turning angle of the movable scroll 22 in FIGS. 6 and 7, in this case as well, as in the above embodiment, the oil supply groove 50 is intermittently straddled by the movable scroll 22. At this time, the one end portion 50a and the other end portion 50b of the oil supply groove 50 are extended along the revolution turning direction of the movable scroll 22 in a range where they are sequentially exposed when viewed from the movable scroll 22 side.

In the case of this modification, the flow of the lubricating oil in the oil supply groove 50 can be further promoted by using the circumferential groove 52 in accordance with the revolving orbiting motion of the movable scroll 22, so that the power loss in the scroll unit 14 is reduced. This can be further reduced, and as a result, the compression efficiency of the compressor 1 can be further improved.
Finally, in the above-described embodiment and modification, a closed scroll compressor using a carbon dioxide refrigerant incorporated in a refrigeration circuit such as a refrigeration air conditioner or a heat pump type hot water heater has been described, but the present invention is not limited thereto. The present invention can be applied to a scroll type fluid machine such as a compressor or an expander in various fields using various working fluids.

1 is a longitudinal sectional view showing a hermetic scroll compressor according to an embodiment of the present invention. It is the top view which looked at the fixed scroll of FIG. 1 from the sliding surface side. It is the top view which looked at the scroll unit of FIG. 1 from the movable scroll side at the predetermined revolution turning angle of the movable scroll. FIG. 4 is a plan view of the scroll unit in which the revolving orbiting motion of the movable scroll has advanced by a predetermined revolution orbit angle from the state of FIG. 3 as viewed from the movable scroll side. It is the top view which looked at the fixed scroll which concerns on the modification of this invention from the sliding surface side. It is the top view which looked at the scroll unit of FIG. 5 from the movable scroll side at the predetermined revolution turning angle of the movable scroll. It is the top view which looked at the scroll unit which the revolution turning motion of the movable scroll advanced only the predetermined revolution turning angle from the state of FIG. 6 from the movable scroll side.

Explanation of symbols

1 Hermetic scroll compressor (scroll type fluid machine)
22 movable scroll 24 fixed scroll 26 movable scroll end plate 26a end plate surface of movable scroll end plate 28 fixed scroll end plate 28a end plate surface of fixed scroll end plate 30 movable scroll wrap 32 fixed scroll wrap 14 scroll unit 44 outer space 46 slide Moving surface 50 Oil supply groove 50a One end 50b The other end 52 Circumferential groove

Claims (2)

Each of the end plates is composed of a fixed scroll and a movable scroll, each of which has a pair of spiral wraps standing on each end plate surface. A scroll unit that forms a compression chamber for the working fluid and moves while reducing the volume of the compression chamber toward the radial center of each end plate;
An outer peripheral space that is formed on the outer peripheral side of the movable scroll and is supplied with lubricating oil having a pressure lower than that of the compression chamber;
A sliding surface that is formed on the end plate surface of the fixed scroll, is supplied with lubricating oil from the outer peripheral space, and the movable scroll slides along with its revolving turning motion;
A lubricating oil supply groove formed on the sliding surface and intermittently straddling the orbiting scroll as the orbiting scroll revolves ;
The oil supply groove is formed in a range in which one end portion and the other end portion of the oil supply groove are sequentially exposed when viewed from the side of the movable scroll when the movable scroll straddles intermittently. A scroll type fluid machine characterized in that it extends along the same . On the end plate surface of the fixed scroll, a circumferential groove for adjusting the pressure of the outer peripheral space is formed on the outer peripheral side of the movable scroll with respect to the oil supply groove,
The scroll type fluid machine according to claim 1 , wherein the one end and the other end communicate with a circumferential groove.

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