KR20110047015A - Scoroll compressor and refrigerator having the same - Google Patents

Abstract

PURPOSE: A scroll compressor and a refrigerating instrument applying the same are provided to enhance the efficiency of a compressor and stably support a rotating scroll by supporting the rotating scroll by the pressure of a back pressure chamber by guiding the oil of a discharge space to the back pressure chamber between a main frame and the rotating scroll. CONSTITUTION: A scroll compressor comprises a frame(20), a fixed scroll(50) and a rotating scroll(60). The frame is installed in a casing(10), which has a closed inner space. The fixed scroll is installed on the frame. The rotating scroll is installed between the frame and the fixed scroll and forms a compression chamber while making rotating movement in a state of being engaged with the fixed scroll. A fluid path is formed in the rotating scroll or the fixed scroll. The fluid of the compression chamber is leaked is guided to the bearing surface between the fixed scroll and the rotating scrolls through the fluid path.

Description

SCROLL COMPRESSOR AND REFRIGERATOR HAVING THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor and a refrigerating machine using the same, and more particularly, to a scroll compressor for lubricating between scrolls while supporting the rear surface of a turning scroll using discharge pressure, and a refrigerating machine using the same.

A scroll compressor is a compressor which compresses refrigerant gas by changing the volume of a compression chamber formed by a pair of opposed scrolls. Scroll compressors are more efficient than reciprocating compressors or rotary compressors, have low vibration and noise, are compact and lightweight, and thus are widely used in air conditioners.

The scroll compressor can be classified into low pressure type and high pressure type according to the pressure of the refrigerant filling the inner space of the casing. In the low pressure scroll compressor, a suction pipe communicates with an inner space of a casing, and a discharge pipe communicates with a discharge side of the compression unit so that refrigerant is indirectly sucked into the compression chamber. On the other hand, in the high pressure scroll compressor, the suction pipe is directly connected to the suction side of the compression unit, and the discharge pipe is connected to the inner space of the casing so that the refrigerant is directly sucked into the compression chamber. In the case of the low pressure scroll compressor, the inner space of the casing is divided into a suction space and a discharge space, and a compression unit is disposed between the suction space and the discharge space.

In the low pressure scroll compressor, a tip seal method and a back pressure method are widely known as a method for sealing between a fixed scroll and a rotating scroll. The tip seal method is to install a tip seal on the end surface of the wrap of each scroll to seal between the compression chamber while the tip seal is in close contact with the opposite hard plate portion, the back pressure method is to press the back of the fixed scroll or swing scroll to scroll both sides It is to seal between the compression chamber while the wrap and the hard plate portion of the close.

In the method of adding the bottom surface of the turning scroll in the back pressure method as described above, the intermediate pressure hole is formed in the turning scroll in the axial direction so that the medium pressure refrigerant compressed in the compression chamber moves between the turning scroll and the main frame. It is known to allow a medium pressure refrigerant moving between the scroll and the mainframe to support the swing scroll.

In this case, in order to lubricate the bearing surface between the fixed scroll and the revolving scroll, an oil supply hole is formed in the revolving scroll to supply oil sucked in the suction space of the casing between the revolving scroll and the fixed scroll. have.

However, in the above-described low pressure type scroll compressor of the conventional back pressure type, the back pressure chamber must maintain a high sealing state to closely close the fixed scroll and the turning scroll to prevent the inter-compression refrigerant leakage. However, a gap is generated between the main frame forming the intermediate compression chamber, the fixed scroll, and the turning scroll, and thus the refrigerant leakage occurs between the compression chambers while the pressure in the back pressure chamber is not kept constant. There was a problem.

Further, in the conventional scroll compressor as described above, the oil supply hole is formed in the swing scroll to supply the oil sucked between the fixed scroll and the swing scroll, but when the compressor operates at low speed, the centrifugal force decreases and The oil may not be sucked smoothly, and this causes a problem that the compressor performance is deteriorated because the friction loss of the compressor is increased while oil is not sufficiently supplied to the bearing surface between both scrolls.

In the conventional scroll compressor as described above, the swing scroll is supported toward the fixed scroll by its back pressure. In this case, when the back pressure supporting the swing scroll is excessively increased, the swing scroll is moved toward the fixed scroll. There was also a problem that the friction loss between the turning scroll and the fixed scroll is increased too close.

It is an object of the present invention to provide a scroll compressor and a refrigerating apparatus employing the same so that the back pressure chamber can maintain a high sealing state, thereby improving compressor efficiency.

Another object of the present invention is to provide a scroll compressor and a refrigerating apparatus to which the oil can be smoothly supplied between both scrolls even when the compressor is operated at a low speed.

Another object of the present invention is to properly support the upper and lower sides of the swing scroll to prevent the swing scroll is in close contact with the main frame or fixed scroll, thereby reducing the friction loss between the two scrolls through the performance of the compressor It is an object of the present invention to provide a scroll compressor that can increase the and a refrigeration apparatus using the same.

In order to solve the object of the present invention, the frame is installed in the casing having a closed inner space; A fixed scroll installed on the frame; And a swing scroll installed between the frame and the fixed scroll to form a compression chamber while pivoting in engagement with the fixed scroll. And a scroll compressor having a flow path formed therein so that the fluid in the compression chamber leaks and is guided to the bearing surface between the fixed scroll and the rotating scroll.

In addition, a casing in which the sealed inner space is divided into a suction space and a discharge space; A frame installed in the casing; A fixed scroll installed on the frame; And a rotating scroll installed between the frame and the fixed scroll to form a compression chamber while pivoting in engagement with the fixed scroll. And a first back pressure flow path is formed in the fixed scroll and the frame to guide the fluid in the discharge space to the bearing surface between the frame and the swing scroll, and the fluid of the compression chamber is formed inside the swing scroll or the fixed scroll. A second back pressure flow path is formed to be leaked and guided to the bearing surface between the fixed scroll and the swing scroll, and a sealing member is provided at both sides of the first back pressure flow path at the outlet side of the first back pressure flow path, respectively, so that the turning scroll There is provided a back pressure chamber for supporting the scroll compressor is provided with a first back pressure groove is formed along the circumferential direction so as to communicate with the outlet of the first back pressure passage between the sealing member.

In addition, a compressor; A condenser connected to the discharge side of the compressor; An expander coupled to the condenser; And an evaporator connected to the inflator and connected to the suction side of the compressor, wherein the compressor includes a bearing between the first back pressure passage and both scrolls for guiding the fluid in the discharge space to the bearing surface between the frame and the turning scroll. There is provided a refrigerating device in which a second back pressure flow passage guiding to a surface is formed.

The scroll compressor according to the present invention and the refrigerating apparatus employing the same support the turning scroll stably by guiding the oil in the discharge space to the back pressure chamber between the main frame and the turning scroll to support the turning scroll at the pressure of the back pressure chamber. In addition, as the oil is filled in the back pressure chamber, the sealing force of the back pressure chamber is increased, so that the swing scroll can be more stably supported, thereby increasing the efficiency of the compressor, and thereby the energy efficiency of the refrigeration apparatus to which the compressor is applied. Can improve.

In addition, a part of the refrigerant or oil compressed in the compression chamber is guided between the fixed scroll and the rotating scroll to lubricate between the scrolls and at the same time preventing the turning scroll from excessively rising and being in close contact with the fixed scroll. It is possible to reduce the friction loss between the through this can further increase the efficiency of the compressor through this can further improve the energy efficiency of the refrigeration apparatus to which the compressor is applied.

Hereinafter, a scroll compressor according to the present invention and a refrigerating apparatus to which the same is applied will be described in detail with reference to an embodiment shown in the accompanying drawings.

1 is a cross-sectional view showing a scroll compressor of the present invention, Figure 2 is a cross-sectional view showing a compression unit in the scroll compressor according to Figure 1, Figure 3 is a perspective view showing a compression unit in the scroll compressor according to Figure 1, Figure 4 is FIG. 5 is an enlarged perspective view illustrating the second back pressure passage in the compression unit, and FIG. 5 is an enlarged view illustrating the second back pressure passage in the compression unit according to FIG. 3.

As shown in FIG. 1, the low-pressure scroll compressor according to the present invention includes a casing 10 having a closed inner space, a main frame 20 and a sub which are respectively fixed to upper and lower inner spaces of the casing 10. A drive motor 40 mounted between the frame 30, the main frame 20 and the subframe 30 to generate a rotational force, and a fixed scroll 50 fixed to the upper surface of the main frame 20. And a pivoting scroll 60 rotatably mounted on an upper surface of the main frame 20 to be engaged with the fixed scroll 50 to form a compression chamber P, and the pivoting scroll 60 and the main frame ( 20 is provided between the Oldham's ring (70) for turning while preventing the rotation of the rotating scroll (60).

The casing 10 is a sealed inner space is divided into the suction space (S1) and the discharge space (S2) by the main frame 20 and the fixed scroll (50) in the suction space (S1) gas suction pipe ( 11) is connected to the gas discharge pipe 12 is connected to the discharge space (S2). And the bottom surface of the suction space (S1) of the casing 10 is filled with oil.

The main frame 20 is formed through the bearing hole 21 in the center thereof, the oil storage groove 22 to collect the oil sucked through the crank shaft 43 to be described later in the upper end of the bearing hole 21 Is formed.

The drive motor 40 is fixed to the inside of the casing (10) and the power is applied from the outside and the stator 41 is disposed with a predetermined gap in the interior of the stator 41 and mutually The rotor 42 rotates while acting, and the crank shaft 43 is coupled to the rotor 42 in a shrink fit and transmits the rotational force of the drive motor 40 to the swing scroll 60. The crankshaft 43 has an oil passage 43a formed therethrough in the axial direction, and an oil pump 44 is installed at the lower end of the oil passage 43a.

The fixed scroll (50) is formed on the bottom surface of the hard plate portion 51, a fixed wrap 52 constituting a pair of two compression chambers (P) in a spiral form, the side of the hard plate portion 51, the casing ( The suction groove 53 is formed in communication with the suction space S1 of the 10, and the discharge port 54 for discharging the compressed refrigerant to the discharge space (S2) of the casing 10 in the center of the upper surface of the hard plate portion 51. ) Is formed. A check valve 55 is installed at the upper end of the discharge port 54 to prevent the refrigerant discharged into the discharge space S2 from flowing back into the compression chamber P.

The orbiting scroll (60) is formed on the upper surface of the hard plate portion 61 of the orbiting wrap (62) forming a pair of compression chamber (P) together with the fixed wrap (52) of the fixed scroll (50) in a spiral form The boss portion 63 is coupled to the crankshaft 43 at the center of the bottom surface of the hard plate portion 61 to receive power from the driving motor 40.

On the other hand, the fixed scroll (50) and the revolving scroll (60) may be formed in an asymmetrical length of about 180 ° longer than the wrap length of the revolving scroll (60), but in some cases The lap lengths of both scrolls 50 and 60 may be formed in the same symmetrical shape.

The scroll compressor of the present invention as described above operates as follows.

That is, when power is applied to the drive motor 40, the crankshaft 43 rotates together with the rotor 42 to transmit rotational force to the turning scroll 60, and the rotational force is transmitted. The scroll 60 is pivoted by the Oldham ring 70 by an eccentric distance from the upper surface of the main frame 20 by the fixed wrap 52 of the fixed scroll 50 and the pivoting wrap of the pivoting scroll 60. A pair of compression chambers P continuously moving between the 62 are formed. And this compression chamber (P) is to move to the center by the continuous swing motion of the swing scroll 60 to compress the refrigerant sucked in the volume decreases.

At the same time, the oil pump 44 installed at the lower end of the crankshaft 43 pumps the oil filled in the casing 10, and the oil passes through the oil flow path 43a of the crankshaft 43. While being sucked to the upper end is supplied to the bearing hole 21 of the main frame 20 or gathered in the oil storage groove 22 of the main frame 20 between the main frame 20 and the turning scroll 60 Lubricate the bearing surface.

On the other hand, the fixed scroll (50) and the revolving scroll (60) is the end surface of the fixed wrap (52) and the revolving wrap (62), respectively, in close contact with the hard plate portion 51, 61 of each scroll (50) 60 The leakage of the refrigerant between the compression chamber (P) must be prevented. To this end, in the related art, as described above, a back pressure chamber is formed between the main frame 20 and the turning scroll 60, and a portion of the refrigerant in the intermediate compression chamber P is formed by drilling a hole in the turning scroll 60. It is introduced into the back pressure chamber so that the turning scroll is supported by the medium pressure of the refrigerant. However, in this case, the sealing state of the back pressure chamber may be poor due to the characteristics of the scroll compressor whose behavior of the swing scroll 60 is not constant. As a result, the refrigerant in the back pressure chamber leaks into the suction space, thereby causing the turning scroll 60 to fail. ) May not be sufficiently supported. When the pivoting scroll 60 cannot be sufficiently supported by the pressure of the back pressure chamber, the compression scroll P is separated between the pivoting end of the pivoting scroll 60 and the fixed scroll 50 and the hard plate portion. Refrigerant leakage may occur and the compressor efficiency may be greatly reduced.

In view of this, in the present invention, a portion of the refrigerant and the oil discharged to the discharge space (S2) is introduced into the back pressure chamber to improve the sealing state of the back pressure chamber by the viscosity of the oil. For example, as shown in FIGS. 1 and 2, the main frame portion 51 of the fixed scroll 50, that is, the upper surface of the hard plate portion 51 of the edge portion where the fixing wrap 52 is not formed, may be formed. A first back pressure flow path 110 penetrates to an upper surface of the top surface 20, that is, the surface forming the pivoting scroll 60 and a bearing surface, and an outlet side of the first back pressure flow path 110 is formed, that is, the main frame ( The sealing member 130 to be described later is installed on both sides of the outlet of the first back pressure passage 110 with the first back pressure passage 110 interposed therebetween at an upper surface of the top surface 20 to form the back pressure chamber 140. .

The first back pressure passage 110 communicates with the first discharge pressure hole 111 formed through the outer hard plate portion 51 of the fixed scroll 50 and the first discharge pressure hole 111. The second discharge pressure hole 112 may be formed through the main frame 20.

As shown in the drawing, the first discharge pressure hole 111 may be formed in the fixed scroll 50 in the axial direction, and in some cases, may be inclined in the fixed scroll 50. As shown in FIG. 3, at the inlet end of the first discharge pressure hole 111, oil discharged into the discharge space S2 and flowing down to the upper surface of the hard plate part 51 of the fixed scroll 50 may be gathered together. A guide groove 113 wider than a cross section of the first discharge pressure hole 111 may be formed so as to be wide. The guide groove 113 is preferably formed in a funnel-shaped inverted trapezoid cross-sectional shape it may be preferable to smooth oil inflow. And the upper surface of the hard plate portion 51 of the fixed scroll 50 is so that the oil flowed down to the upper surface of the hard plate portion 51 of the fixed scroll 50 can be guided to the first discharge pressure hole 111 more smoothly. May be inclined toward the first discharge pressure hole 111.

The second discharge pressure hole 112 is formed in a 'U' shape in the turning scroll, the inlet end of the second discharge pressure hole 112 is in communication with the first discharge pressure hole 111 while the outlet end Is formed to communicate with the back pressure chamber 140, that is, the bearing surface between the main frame 20 and the swing scroll (60). The second discharge pressure hole 112 may be formed such that a single flow path, that is, an outlet, communicates with the back pressure chamber 140, but in some cases, a plurality of flow paths, that is, the middle of the second discharge pressure hole 112, may be formed. The exhaust hole (not shown) may be further formed toward the suction space S1 of the casing 10. In the case where the exhaust hole is formed, when the refrigerant flows into the second discharge pressure hole 112, the refrigerant leaks into the suction space S1 so that pure oil is introduced into the back pressure chamber 140 as much as possible. do. In this case, the exhaust hole may have a smaller inner diameter than the inner diameter of the second discharge pressure hole 112, thereby reducing the pressure of the refrigerant leaking from the second discharge pressure hole 112 to the suction space S1. It may be desirable. Of course, the exhaust hole may be formed in the first discharge pressure hole.

In addition, a guide tube 114 may be inserted between the first discharge pressure hole 111 and the second discharge pressure hole 112 so that both holes 111 and 112 may communicate without being distorted. To this end, the first discharge pressure hole 111 is wider than the second discharge pressure hole 112, and the guide tube 114 is extended to the insertion end of the second discharge pressure hole 112. And a guide tube 114 inserted into the second discharge pressure hole 112 is inserted into the first discharge pressure hole 111 to form the first discharge pressure hole 111 and the second discharge pressure hole 112. It may be desirable to prevent the oil from leaking into the joint between them.

The sealing members 130 are inserted into and coupled to the sealing grooves 23 provided on the upper surface of the main frame 20, respectively. The sealing members 130 may be manufactured in any shape as long as it can prevent the refrigerant and oil from leaking in the radial direction. In this embodiment, a sealing member which is a kind of face seal having elasticity therein may be applied to increase the sealing force. For example, the sealing member of the present embodiment is formed in a cross-sectional shape (C) as shown in Figure 2, the one side is in close contact with the bottom surface of the swing scroll 60 and the sealing portion 131 The support part 132 is inserted into the inner space 131a and elastically supports the sealing part 131.

Both the sealing part 131 and the support part 132 are formed in an annular shape when projecting, and the plurality of sealing grooves 23 into which the sealing members 130 are inserted are also formed in an annular shape when projecting.

Here, as shown in FIG. 2, a radial interval between the sealing members 130, that is, a cross section of the back pressure chamber 140 may be a cross section of the first back pressure passage 110, that is, the second discharge pressure hole 112. It is preferable not to be smaller than at least, preferably to be large, to widen the cross-sectional area of the back pressure chamber 140 to stably support the turning scroll 60.

The back pressure chamber 140 may be formed to have a flat surface to form a bearing surface, but as shown in FIG. 2, a first back pressure groove 141 having a predetermined depth and width may be formed. In this case, the refrigerant and the oil flowing into the back pressure chamber 140 through the first back pressure passage 110, that is, the second discharge pressure hole 112, are quickly moved along the first back pressure groove 141. 140 is moved to the whole, so that the entire pressure of the back pressure chamber 140 can be uniformed quickly, so that the swing scroll 60 can be more stably supported.

For example, the first back pressure groove 141 is formed in an annular shape along the circumferential direction, and the outlet of the first back pressure passage 110, that is, the second discharge pressure hole 112, is formed in the first back pressure groove 141. It is preferable that the outlet of) is formed to communicate. The cross section of the first back pressure groove 141 may be smaller than the cross section of the back pressure chamber 140. In addition, the first back pressure groove 141 may be formed in a rectangular cross-sectional shape, but it may be more advantageous that the first back pressure groove 141 is formed in a semi-circular cross section or a trapezoidal cross-sectional shape in order to move the refrigerant and oil quickly.

On the other hand, although not shown in the drawings, the sealing grooves may be formed on the bottom surface of the turning scroll. Even in this case, the sealing members may be formed in the same manner. The first back pressure groove may be formed on a bottom surface of the swing scroll. Even in this case, the shape of the first back pressure groove may be formed in the same manner as in the above-described embodiment.

Effects of the scroll compressor according to the present invention as described above are as follows.

That is, when the turning scroll 60 is pivoting, the refrigerant and oil sucked into the suction space S1 of the casing 10 are compressed through the suction groove 53 of the fixed scroll 50. The refrigerant and oil are sucked into P) and gradually move toward the center along the movement trajectory of the compression chamber P, and then discharged to the discharge space S2 of the casing 10 through the discharge port 54.

While the refrigerant and oil discharged into the discharge space S2 collide with the inner wall surface of the casing 10 constituting the discharge space S2, the refrigerant moves to the refrigeration cycle apparatus through the gas discharge pipe 12. Most of the oil flows down the upper surface of the fixed scroll 50 along the inner wall surface of the casing 10. The oil flowing down the upper surface of the fixed scroll 50 is collected around the first discharge pressure hole 111 constituting the first back pressure passage 110. In this case, when the guide groove 113 is formed on the upper surface of the fixed scroll 50, the oil may be collected into the first discharge pressure hole 111 more quickly.

The oil gathered into the first discharge pressure hole 111 flows into the first discharge pressure hole 111 by the weight of the oil and the pressure of the discharge space S2, and the oil is again returned to the main frame 20. It flows into the back pressure chamber 140 between the main frame 20 and the turning scroll 60 through the second discharge pressure hole (112). Then, the oil flowing into the back pressure chamber 140 increases the pressure of the back pressure chamber 140 to pressurize the back surface of the swing scroll 60 so that the swing scroll 60 is pushed up to closely contact the fixed scroll 50. Done. As a result, the compression chamber P between the fixed scroll 50 and the turning scroll 60 is tightly sealed to prevent refrigerant leakage from the compression chamber P, thereby improving the efficiency of the compressor.

As described above, the refrigerant and the oil discharged into the discharge space S2 are introduced into the back pressure chamber 140 so that a relatively large amount of the refrigerant and the oil may be supplied to the back pressure chamber 140. . That is, as the inlet end of the first back pressure passage 110 forms a discharge pressure, the oil is pressurized by the pressure difference, whereby the oil in the discharge space S2 can be smoothly supplied to the back pressure chamber 140. It can be.

As such, since a relatively large amount of oil is supplied to the back pressure chamber 140, even if some unstable behavior occurs due to the movement characteristics of the scroll compressor, the oil filled in the back pressure chamber 140 is sealed. It is possible to prevent the pressure in the back pressure chamber 140 from lowering by blocking the gap between the rotating scroll 140 and the rotating scroll 60, thereby stably supporting the rotating scroll 60. At this time, when an exhaust hole (not shown) is formed in the middle of the second discharge pressure hole 112, a small amount of refrigerant flowing into the first back pressure passage 110 is sucked through the exhaust hole (S1). Due to leakage to the back pressure chamber 140, only the oil can be filled as possible. In addition, when the oil is excessively supplied to the back pressure chamber 140, the pressure of the back pressure chamber 140 is excessively increased while excessively raising the turning scroll 60, rather than friction loss between the fixed scroll (50) This may be caused, but even in this case, a part of the oil flowing into the first back pressure passage 110 may leak to the suction space S1 through the exhaust hole to maintain the pressure in the back pressure chamber at an appropriate pressure. .

On the other hand, when excessive refrigerant and oil flow into the back pressure chamber through the first back pressure passage, the pressure in the back pressure chamber is excessively high, the turning scroll is excessively in close contact with the fixed scroll, and friction loss between both scrolls is increased. Can be weighted. Therefore, in order to increase the performance by reducing friction loss between both scrolls, the upper thrust bearing surface of the swing scroll, that is, the surface forming the thrust bearing surface together with the bottom surface of the fixed scroll, supplies a buffer with a constant pressure to cushion the oil. It may be desirable.

To this end, in the present invention, as shown in Figs. 1 to 5, in the hard plate portion 61 of the turning scroll 60, a medium pressure refrigerant in the middle of the compression chamber P, that is, the intermediate compression chamber, is fixed to the fixed scroll ( A second back pressure flow path 120 for guiding to the thrust bearing surface between the 50 and the turning scroll 60 may be formed in a radial direction.

The second back pressure passage 120 extends radially from the first intermediate pressure groove 121 and the first intermediate pressure groove 121 formed axially in the intermediate compression chamber P by a predetermined depth. And the second intermediate pressure groove 122 whose outer end is blocked, and the thrust bearing surface opposite to the fixed scroll 50 at the outer end of the second intermediate pressure groove 122 by a predetermined depth in an axial direction. The third intermediate pressure groove 123 is formed.

The third intermediate pressure groove 123 may have a cross section the same as a cross section of the second discharge pressure hole 112 of the first back pressure passage 110, but the orbiting scroll 60 may have a fixed scroll 50. In order to seal stably), it may be preferable to be formed smaller than the cross section of the second discharge pressure hole (112). Here, the pressure supplied through the first back pressure passage 110 is a discharge pressure and the pressure supplied through the second back pressure passage 120 is an intermediate pressure, for example, the outlet of the first back pressure passage 110. Even if the end face of the second back pressure passage 120 has the same cross section, the turning scroll 60 may float due to the pressure difference. However, when the compressor is started, that is, when the internal pressure of the casing 10 does not sufficiently increase, the intermediate compression chamber P may be higher, so that the pressure of the second back pressure passage 120 may be higher than the first back pressure passage ( It may be higher than or equal to the pressure of 110). Therefore, in consideration of such a case, the second discharge pressure hole 112 should be formed slightly wider than the third intermediate pressure groove 123 so that a larger amount of refrigerant and oil are supplied to the first back pressure passage 110 so that the turning scroll 60 may be injured.

And the exit of the second back pressure passage 120, that is, the end of the third intermediate pressure groove 123 is always in the bearing surface range with the fixed scroll 50 during the swinging movement of the swinging scroll 60 as shown in FIG. Preferably, the outlet of the second back pressure flow path 120, the medium pressure refrigerant and the oil supplied through the second back pressure flow path 120 to the bearing surface with the fixed scroll (50) quickly The second back pressure groove 151 may be formed to be diffused.

The second back pressure groove 151 may be formed in an arc shape extending in the circumferential direction, such as the first back pressure groove 141 described above, and the cross section of the second back pressure groove 151 may be at least a third intermediate pressure groove. It may be desirable not to be formed smaller than the cross section of 123.

The scroll compressor as described above has the following effects.

That is, a portion of the refrigerant (or oil mixed with the refrigerant) compressed in the compression chamber P passes through the second back pressure passage 120, and the upper thrust bearing between the fixed scroll 50 and the turning scroll 60. It flows into cotton. Then, the refrigerant and the oil flowing into the third intermediate pressure groove 123 flow into the second back pressure groove 151 provided at the end of the third intermediate pressure groove 123 and spread widely on the upper thrust bearing surface. Then, an intermediate pressure is formed between the fixed scroll 50 and the revolving scroll 60 by the pressure of the refrigerant flowing into the upper thrust bearing surface, and thus the pressure of the fluid flowing through the first back pressure passage 110. While forming the force (F2) corresponding to the force (F1) by the turning scroll 60 can be prevented from rising to an appropriate amount or more through which the turning scroll 60 is excessively fixed to the fixed scroll (50) It is possible to improve the performance of the compressor by preventing the friction loss from being in close contact.

In addition, when a predetermined amount of oil is supplied to the upper thrust bearing surface of the turning scroll through the second back pressure passage 120, the upper thrust bearing surface is lubricated by the oil, and the turning movement of the turning scroll 60 is performed. The friction loss between both scrolls can be reduced to further improve compressor performance.

On the other hand, the second back pressure flow path 220 may be formed in the hard plate portion 51 of the fixed scroll (50) as shown in FIG. In this case, the shape may be formed similar to that formed in the turning scroll 60 as described above. However, in this case, as the second back pressure flow path 220 is formed in the hard plate portion 51 of the fixed scroll 50, the processing length becomes longer than that formed in the hard plate portion 61 of the turning scroll 60. However, the workability and stability can be improved compared to that formed in the hard plate portion 61 of the relatively thin turning scroll 60. In the drawings, reference numeral 221 denotes a first intermediate pressure groove, 222 denotes a second intermediate pressure groove, and 223 denotes a third intermediate pressure groove.

When the scroll compressor according to the present invention is applied to a refrigerator, the efficiency of the refrigerator can be improved.

For example, in the refrigerator 700 having a refrigerant compression type refrigeration cycle including a compressor, a condenser, an expander and an evaporator as shown in FIG. 8, the main board 710 controls the overall operation of the refrigerator in the refrigerator 700. The scroll compressor (C) is connected to the bottom of the scroll compressor (C), and the back pressure chamber between the main frame and the turning scroll installed inside the scroll compressor (C) communicates with the discharge space, and the intermediate compression chamber is placed between the fixed scroll and the turning scroll. By communicating with the bearing surface of the roller, it stably supports the swing scroll while effectively lubricating between the swing scroll and the fixed scroll, and prevents the floating scroll from excessively rising, thereby reducing the friction loss between the swing scroll and the fixed scroll. It is possible to increase the performance of the scroll compressor through this and the Energy efficiency can be improved.

The scroll compressor according to the present invention can be widely used in refrigeration machines such as air conditioners.

1 is a cross-sectional view showing a scroll compressor of the present invention,

2 is a cross-sectional view showing a compression unit in the scroll compressor according to FIG.

3 is a perspective view of a compression unit in the scroll compressor according to FIG. 1;

4 is an enlarged perspective view of the second back pressure passage in the compression unit according to FIG. 3;

FIG. 5 is an enlarged view illustrating the second back pressure passage in the compression unit according to FIG. 3;

6 is a cross-sectional view showing a state in which the refrigerant and the oil is guided to each bearing surface in the scroll compressor according to FIG.

7 is a cross-sectional view showing another embodiment of the second back pressure passage in the scroll compressor according to FIG. 1;

8 is a schematic view showing a refrigerator equipped with a scroll compressor according to FIG.

** Description of symbols for the main parts of the drawing **

10: casing 20: mainframe

50: fixed scroll 60: turning scroll

110: first back pressure passage 111: first discharge pressure hole

112: second discharge pressure hole 120: second back pressure flow path

121: first intermediate pressure groove 122: second intermediate pressure groove

123: third intermediate pressure groove 130: sealing member

131: sealing part 132: support part

140: back pressure chamber

Claims (13)

A frame installed in the casing having a closed inner space; A fixed scroll installed on the frame; And A swing scroll which is installed between the frame and the fixed scroll and forms a compression chamber while pivoting in engagement with the fixed scroll; Including, And a flow path formed inside the swing scroll or the fixed scroll so that fluid in the compression chamber leaks and is guided to a bearing surface between the fixed scroll and the swing scroll. The method of claim 1, And at least one of the bearing surfaces of the fixed scroll and the revolving scroll has a groove communicating with the flow path. The method of claim 2, And a cross section of the groove is not smaller than a cross section of the flow path. The method of claim 2, And the groove is formed in an arc shape along the circumferential direction. A casing in which the sealed inner space is divided into a suction space and a discharge space; A frame installed in the casing; A fixed scroll installed on the frame; And A swing scroll which is installed between the frame and the fixed scroll and forms a compression chamber while pivoting in engagement with the fixed scroll; Including, The fixed scroll and the frame is formed with a first back pressure flow path for guiding the fluid in the discharge space to the bearing surface between the frame and the swing scroll, A second back pressure flow path is formed in the swing scroll or the fixed scroll so that fluid in the compression chamber leaks and is guided to the bearing surface between the fixed scroll and the swing scroll. Sealing members are provided on both sides of the first back pressure flow path at the outlet side of the first back pressure flow path to form a back pressure chamber for supporting the turning scroll. And a first back pressure groove formed along the circumferential direction between the sealing members so as to communicate with the outlet of the first back pressure flow path. The method of claim 5, And a cross section of the first back pressure groove is not smaller than a cross section of an outlet side of the first back pressure passage. The method of claim 5, And at least one of the bearing surfaces of the fixed scroll and the swing scroll, a second back pressure groove communicating with the second back pressure flow path. The method of claim 7, wherein And a cross section of the second back pressure groove is not smaller than a cross section of the second back pressure passage. The method of claim 8, And the second back pressure groove is formed in an arc shape along the circumferential direction. The method of claim 5, And the exhaust hole is further formed in the first back pressure passage to communicate with the suction space. The method of claim 5, A guide tube is installed at a portion where the first back pressure passage is in contact with the frame and the fixed scroll, and the guide tube is installed such that both ends thereof are inserted into the frame and the fixed scroll, respectively. The method of claim 5, An outlet side cross section of the first back pressure passage is larger than the outlet side cross section of the second back pressure passage. compressor; A condenser connected to the discharge side of the compressor; An expander coupled to the condenser; And And an evaporator connected to the inflator and connected to the suction side of the compressor. The compressor comprises a compressor of any one of claims 1 to 14.

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