KR20100096794A - Scoroll compressor and refrigsrator having the same - Google Patents

Abstract

PURPOSE: A scroll compressor and a freezing device using the same are provided to simplify the assembling process of an injection tube and to eliminate the need for a sealing member by the injection tube connected to an injection path by press-fit. CONSTITUTION: A scroll compressor comprises a casing(10), a frame, a fixed scroll(40) and a rotating scroll. The casing comprises a closed inner space. The frame is fixed to the inner space of the casing. The fixed scroll is fixed to the frame. The rotating scroll rotates with the fixed scroll and forms a pair of compression chambers which continuously move. An injection tube(6) is connected to be communicated with the compression chamber through the casing. The injection tube is connected to a freezing cycle from the outside the casing to guide a part of the refrigerant to the middle compression chamber. The injection tube is connected to be press-fit to the frame making tight contact with the inner circumference of the casing or to the outer circumference of the fixed scroll.

Description

SCROLL COMPRESSOR AND REFRIGSRATOR HAVING THE SAME}

The present invention relates to a scroll compressor for varying the compressor capacity by bypassing the refrigerant from the middle of the refrigeration cycle to the intermediate compression chamber, and a refrigerating apparatus using the same.

Generally, a scroll compressor is a compressor which compresses refrigerant gas by changing the volume of the compression chamber formed by a pair of opposing 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 may be classified into a low pressure type and a high pressure type according to the type of refrigerant supplied to the compression chamber. That is, in the low pressure scroll compressor, the refrigerant is indirectly sucked into the compression chamber through the inner space of the casing, and the inner space of the casing is divided into the suction space and the discharge space. On the other hand, in the high pressure scroll compressor, the refrigerant is directly supplied to the compression chamber without passing through the inner space of the casing and then discharged into the inner space of the casing, and the entire inner space of the casing is a discharge space.

The scroll compressor may be classified into a tip seal method and a back pressure method by a sealing method of a compression chamber. That is, the tip seal method is a method in which a tip seal is installed at the lap end of each scroll so that the tip seal floats while the compressor is in operation and is in close contact with the hard plate portion of the opposite scroll. On the other hand, in the back pressure method, a back pressure chamber is formed on the rear surface of one scroll and the oil or refrigerant of medium pressure is induced in the back pressure chamber so that the scroll is pressed against the opposite scroll by being pushed by the pressure in the back pressure chamber. Generally, the tip seal method is applied to a low pressure scroll compressor, while the back pressure method is applied to a high pressure scroll compressor.

In addition, the scroll compressor may be classified into a fixed capacity type and a variable capacity type by the circulation method of the refrigerant. In other words, in the fixed capacity type, the entire refrigerant discharged from the compressor is circulated through the refrigeration cycle consisting of the condenser, the expander, and the evaporator and sucked to the suction side of the compressor. Bypass is introduced again into the intermediate compression chamber of the compressor and the rest is sucked through the refrigeration cycle to the suction side of the compressor. In general, the variable displacement scroll compressor pipes the injection pipe at the outlet of the condenser, communicates the injection pipe to the intermediate compression chamber of the compressor, and circulates the refrigerant in the middle of the injection pipe or at the point where the injection pipe is piped. Valves are installed to control this.

However, in the conventional scroll compressor as described above, as the injection pipe is connected to the upper surface of the fixed scroll spaced apart from the inner circumferential surface of the compressor casing, the connection pipe for connecting the injection pipe or the injection pipe is closely coupled to the fixed scroll. In order to provide a sealing member such as an O-ring, and thus, the assembly process for connecting the injection tube is complicated, and there is a problem in that the O-ring, which is an organic material, reacts with the refrigerant or is damaged by high heat, thereby lowering the sealing force. For example, as shown in FIG. 1, the intermediate connecting pipe 11 is inserted into the compressor casing 10 to be welded (W1), and the internal connecting pipe (12a) of the fixed scroll 12 is inserted into the injection passage 12a. 13 is inserted and coupled, and the outer connecting pipe 14 inserted into the intermediate connecting pipe 11 and welded (W2) is inserted into the inner connecting pipe 13 and welded (W3). In this case, the intermediate connecting pipe 11 is welded to the casing 10 and the external connecting pipe 14 is welded to the intermediate connecting pipe 11 and the internal connecting pipe 13, as well as the welding site is a lot. If the oil installed between the inner connecting pipe 13 and the injection passage 12a is damaged as described above, the sealing force for the compression chamber is lowered, which may cause the refrigerant to leak.

The present invention solves the problems of the conventional scroll compressor as described above, when the injection pipe is connected to the injection passage to maintain the sealing force without a separate sealing member such as O-ring to facilitate the connection of the injection pipe SUMMARY OF THE INVENTION An object of the present invention is to provide a scroll compressor and a refrigerating device having the same, which can be maintained and a reliability of the sealing force.

In order to achieve the object of the present invention, the casing having a closed inner space; A frame fixed to the inner space of the casing; A fixed scroll fixed to the frame; And a turning scroll which engages with the fixed scroll to form two pairs of compression chambers which are continuously moved while pivoting, and connected to a refrigeration cycle outside the casing to guide a part of the refrigerant to the intermediate compression chamber. An injection tube is coupled to communicate with the compression chamber through the casing, and the injection tube is provided with a scroll compressor that is pressed into and coupled to the outer circumferential surface of the frame or the fixed scroll that is in close contact with the inner circumferential surface of the casing.

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 is press-fitted into an outer circumferential surface of a frame or fixed scroll in which an injection tube communicating with an intermediate compression chamber in the middle of a refrigeration cycle is in close contact with the compressor casing. There is provided a refrigeration machine consisting of a scroll compressor which is combined.

The scroll compressor and the refrigerating device having the same according to the present invention simplifies the assembly process of the injection tube by pressing and injecting the injection tube into the injection passage, and excludes the use of the sealing member. Due to this, it is possible not only to prevent the deterioration of the sealing force of the compressor but also to prevent the refrigerant injected into the intermediate compression chamber through the injection passage from leaking through the back pressure passage, thereby improving the performance of the refrigerating device having the scroll compressor. Can be.

Hereinafter, a refrigerator compressor including the scroll compressor according to the present invention will be described in detail with reference to an embodiment shown in the accompanying drawings.

As shown in FIG. 2, the high-pressure scroll compressor according to the present invention includes a casing 10 having a sealed inner space, a main frame 20 and a sub which are respectively fixed to upper and lower inner spaces of the casing 10. A frame (not shown), a drive motor 30 mounted between the main frame 20 and a subframe (not shown) and generating rotational force, and fixedly installed on an upper surface of the main frame 20 and the gas suction pipe. A fixed scroll 40 to which the SP is directly coupled, and a pivoting scroll 50 rotatably mounted on an upper surface of the main frame 20 to form a compression chamber P by engaging the fixed scroll 40. It is installed between the turning scroll 50 and the main frame 20 includes an Oldham's ring (not shown) for turning while preventing the turning scroll 50 from rotating.

The casing 10 has a sealed inner space divided into an upper space S1 and a lower space S2 by the main frame 20 and the fixed scroll 40, and the upper space S1 and the lower space ( S2) maintains a high pressure state, and the bottom surface of the casing 10 (S2) is filled with oil. The gas suction pipe SP is coupled to the upper space S1 of the casing 10, and the gas discharge pipe DP is connected to the lower space S2 of the casing 10.

The main frame 20 has a bearing hole 21 formed in the center thereof, and an oil pocket 22 is formed at the upper end of the bearing hole 21 so that oil drawn up through the drive shaft 32 to be described later is collected. do. In addition, a back pressure groove 23 is formed at an upper edge of the main frame 20 to form a back pressure chamber S3 having a medium pressure by mixing a part of the refrigerant sucked with a part of the oil sucked up, and the back pressure groove 23. Inside the seal member 60 is inserted into a sealing groove (unsigned) is formed in an annular shape to seal the oil accumulated in the oil pocket 22 to maintain a high pressure. The back pressure chamber S3 is a space in which the back pressure groove 23 of the main frame 20 and the hard plate portion 41 of the fixed scroll 40 to be described later and the hard plate portion 51 of the turning scroll 50 to be described later are combined. To form.

The drive motor 30 is fixed to the inside of the casing 10 and is disposed with a stator (not shown) having a coil 31 and a predetermined gap inside the stator 31 to receive power from the outside. Rotor (not shown) that rotates while interacting with the stator, and the drive shaft 32 is coupled to the rotor in a shrink fit to transmit the rotational force of the drive motor 30 to the swing scroll (50). The drive shaft 32 has an oil passage 32a formed therethrough in the axial direction, and an oil pump (not shown) is installed at the lower end of the oil passage 32a.

The fixed scroll 40 is formed on the bottom surface of the hard plate portion 41, the fixed wrap 42 constituting a pair of two compression chamber (P) in a spiral form, the side of the hard plate portion 41 is the gas suction pipe A suction port 43 is formed in which SP directly communicates, and a discharge port 44 for discharging the compressed refrigerant into the upper space S1 of the casing 10 is formed at the center of the upper surface of the hard plate part 41. The compression chamber P and the back pressure chamber S3 are disposed between the lap and the lap forming the compression chamber P at the bottom surface of the hard plate part 41, that is, the surface forming the thrust bearing surface together with the turning scroll 50. The back pressure passage 110 is formed to communicate.

3 and 4, the back pressure passage 110 includes a first back pressure hole 111 communicating with the back pressure chamber S3 and a second back pressure hole 112 communicating with the compression chamber P. As shown in FIG. And a third back pressure hole 113 formed at a predetermined depth in the radial direction on the outer circumferential surface of the fixed scroll 40 so that the first back pressure hole 111 and the second back pressure hole 112 communicate with each other. The first back pressure hole 111 may be smoothly communicated with the back pressure groove 23 at the outlet end of the first back pressure hole 111, that is, the surface facing the back pressure groove 23. A communication groove 114 wider than the hole 111 is formed. The communication groove 114 may be formed in a radially long rectangular shape or may be formed in a circular groove wider than the first back pressure hole 111. In addition, the diameters d1, d2, and d3 of the back pressure holes 111, 112, and 113 may be formed to be substantially the same, so that the flow path resistance may be reduced.

The first back pressure hole 111, the second back pressure hole 112, and the third back pressure hole 113 are formed to form one flow path, and the one flow path alternates with the pair of compression chambers P. It is formed to communicate. That is, one second back pressure hole 112 is formed, and the second back pressure hole 112 is formed to be positioned at the center between neighboring fixing wraps 42 and in the inner compression chamber according to the pressure difference. Preferably, the inner diameter d1 of the second back pressure hole 112 is not greater than the wrap thickness t of the turning scroll so that the refrigerant does not leak into the outer compression chamber.

The blocking member 120 is inserted into the third back pressure hole 113 by a predetermined depth from the outer end thereof so that the third back pressure hole 113 is separated from the inner space of the casing 10. The blocking member 115 may be press-fitted into a non-ferrous metal having a relatively elasticity and sealed or may be fastened to a predetermined depth by using a metal bolt provided with a thread as shown in FIGS. 3 and 4. In the case where the metal bolt is used, it may be preferable to seal the head of the metal bolt by sealing sealing 116.

As shown in FIG. 2, the turning scroll 50 forms a pair of compression chambers P together with the fixing wrap 42 of the fixed scroll 40 on the upper surface of the hard plate portion 51 ( 52 is formed in a spiral shape, and a boss portion 53 is coupled to the driving shaft 32 at the center of the bottom surface of the hard plate portion 51 to receive the power of the driving motor 30.

Here, the fixed wrap 42 and the swing wrap 52 may be formed symmetrically with the same wrap length, the wrap length is different, that is, the swing wrap is formed in an asymmetric shape about 180 ° long It may be.

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

That is, when power is applied to the drive motor 30, the drive shaft 32 rotates with the rotor to transmit a rotational force to the turning scroll 50, the rotational scroll 50 received this rotational force Is rotated by an eccentric distance from the upper surface of the main frame 20 by the Oldham ring 60 between the fixed wrap 42 of the fixed scroll 40 and the turning wrap 52 of the orbiting scroll 50. A pair of compression chambers P continuously moving are formed in the. In addition, the compression chamber P moves to the center by the continuous swing motion of the swing scroll 50 to compress the refrigerant sucked by the volume decrease.

At the same time, in the oil pump (not shown) installed at the lower end of the drive shaft 32 to pump the oil filled in the casing 10, the oil is the upper end through the oil passage 32a of the drive shaft 32 While some of the oil is supplied to the bearing hole 21 of the main frame 20, some of the oil is scattered from the upper end of the driving shaft 32 and flows into the back pressure chamber S3 of the main frame 20. . The oil flowing into the back pressure chamber S3 supports the turning scroll 50 so that the turning scroll 50 rises toward the fixed scroll 40, and thus the fixed wrap 42 and the turning wrap 52. The compression chamber P is sealed while being in close contact with each of the hard plate portions 51 and 41 corresponding thereto.

In this state, the turning scroll 50 continuously compresses the refrigerant, and a portion of the compressed refrigerant moves to the back pressure chamber S3 through the back pressure passage 110 to move the back pressure chamber. The pressure of S3 is kept constant. Here, only one outlet of the back pressure passage 110, that is, the second back pressure hole 112 is formed, but the second back pressure hole 112 is disposed in both compression chambers P with the turning wrap 52 interposed therebetween. As each alternately communicates, the oil may be uniformly supplied to each compression chamber P through the back pressure passage 110.

On the other hand, when the scroll compressor is a variable displacement type, the compression capacity of the scroll compressor is increased by reflowing the refrigerant into the intermediate compression chamber of the compressor in the middle of the refrigerating cycle including the scroll compressor, that is, at the outlet of the condenser. You can.

For example, as illustrated in FIG. 7, an injection pipe 6 is formed in the middle of the refrigerant pipe 5 connecting the condenser 2 and the expander 3 of the refrigerating cycle, that is, at the outlet side of the condenser 2. The injection pipe 6 is connected to the injection passage 120 provided in the fixed scroll 40 of the scroll compressor 1 shown in FIGS. 2 and 3. A bypass valve 7 for controlling the flow of the refrigerant may be installed at the middle of the injection pipe 6 or at a point where the injection pipe 6 is branched.

To this end, as shown in Figure 5 and 6, the fixed scroll 40 is formed with an injection passage 120 penetrating to the outer peripheral surface in the compression chamber. The inlet end of the injection passage 120 is formed on the outer circumferential surface of the fixed scroll 40, that is, the surface that can be in close contact with the inner circumferential surface of the casing 10, the through hole 10a of the casing 10 to be described later. Through the inlet of the injection passage 120 can be easily identified. In this way, when the injection pipe 6 is press-fitted into the injection passage 120, not only the press position can be easily held, but also the sealing end side of the injection passage 120 comes into close contact with the casing 10. It may be desirable.

The injection passage 120 has a first injection hole 121 formed at a predetermined depth in the radial direction on the outer circumferential surface of the fixed scroll 40, and at almost the end of the first injection hole 121 to the intermediate compression chamber. The second injection hole 122 is formed in the axial direction so as to penetrate.

The first injection hole 121 is formed to be stepped in the middle thereof, and one side thereof, that is, the outer circumferential surface side to which the injection tube 6 is connected, and the compression chamber side opposite to the opposite side are narrowly formed. The injection chamber side end of the injection passage 120, that is, the end of the second injection hole 122 is formed not to be larger than the thickness of the turning wrap 52 of the turning scroll 50 is injected through the injection passage 120 It may be desirable because the refrigerant communicates with both compression chambers together to prevent leakage of the refrigerant.

The first injection hole 121 extends from the inside of the first injection hole 121 to the outside of the casing 10 so that the outer circumferential surface thereof is pressed against the inner circumferential surface of the first injection hole 121. The pipe 131 is press-fitted, the injection pipe 6 is inserted into the first connecting pipe 131 is welded (W5) coupled. The first connection pipe 131 is preferably formed of the same material as that of the injection pipe 6, that is, the same copper material can increase the welding force.

The second connecting pipe 132 is inserted and welded to the outer circumferential surface of the first connecting pipe 131, and the second connecting pipe 132 is inserted into the casing 10 to be welded (W6). A through hole 10a is formed in the casing 10 so that the second connecting pipe 132 may be inserted. Here, in order to easily press the first connector pipe 131 into the first injection hole 121, the entire inlet of the first injection hole 121 is viewed from the outside of the casing 10. It is good to be able to check through the through hole (10a) of the). Therefore, it may be preferable that the diameter of the through hole 10a is wider than that of the injection passage 120 and the through hole 10a and the injection passage 120 are formed concentrically. In this case, the first connecting pipe 131 has a wide outer diameter connected to the injection tube 6 and a small inner diameter pressed into the first injection hole 121.

In addition, the injection passage 120, more precisely, the second injection hole 122 may leak refrigerant into the back pressure chamber S3 depending on the formation position of the compressor, thereby degrading the performance of the compressor. It may be. Therefore, the second injection hole 122 is formed to have a phase difference of at least 30 ° or more precisely closer to the discharge side of the compression chamber than the back pressure passage 110 is injected into the intermediate compression chamber through the injection passage 120. It is preferable to effectively prevent the refrigerant from leaking into the back pressure passage 110. In addition, the diameter of the second injection hole 122 may not be smaller than the diameter of the back pressure passage 110 so that the diameter of the second injection hole 122 may be substantially the same.

Meanwhile, in the above-described embodiment, the injection passage is formed in the fixed scroll, but the injection passage may be formed to communicate with each other in the main frame and the fixed scroll, although not shown in the drawing. In this case, the inlet side of the injection passage is formed in the main frame, while the outlet side of the injection passage is formed in the fixed scroll. And it may be preferable that the inlet side of the injection passage is formed on the outer circumferential surface of the main frame in close contact with the inner circumferential surface of the casing as in the above-described embodiment.

In this way, as the injection pipe or the connection pipe connected to the injection pipe is press-fitted into the injection passage, the assembly process of assembling the injection pipe into the injection passage can be simplified and the manufacturing cost can be lowered. By eliminating the use of a sealing member such as oil in the process of connecting the pipe, it is possible to prevent the sealing force of the compression chamber from being lowered due to damage of the sealing member.

In addition, the interval between the injection passage and the back pressure passage maintains an appropriate phase difference, thereby preventing the refrigerant injected into the intermediate compression chamber through the injection passage from leaking into the back pressure chamber, thereby improving the performance of the scroll compressor.

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

For example, as shown in FIG. 8, the refrigerator 700 of the present invention includes a scroll compressor 1, a condenser 2, an expander 3, and an evaporator 4, and a part of the refrigerant passing through the condenser 2. It is made of a refrigerant compression type refrigeration cycle including an injection flow path to be injected into the intermediate compression chamber of the scroll compressor (1) again. In addition, the scroll compressor 1 is connected to the main board 710 for controlling the overall operation of the refrigerator 700, and the fixed scroll is installed in the scroll compressor 1 in the freezer 700. It forms a back pressure passage for flowing out the refrigerant from the intermediate compression chamber to the back pressure chamber and an injection passage for reflowing the refrigerant from the condenser outlet to the intermediate compression chamber. Here, the injection tube may be coupled to the injection passage as described above by pressing, and may be formed so that the interval between the back pressure passage and the injection passage is at least 30 ° or more.

In this way, by injecting and injecting the injection pipe into the injection passage, the assembly process of the injection pipe can be simplified and the use of the sealing member can be eliminated, thereby preventing the lowering of the sealing force of the compressor due to damage of the sealing member when the sealing member is used. In addition, the refrigerant injected into the intermediate compression chamber through the injection passage can be prevented from leaking through the back pressure passage, so that the performance of the refrigerating apparatus having a scroll compressor can be improved.

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

Figure 1 is a longitudinal sectional view showing a connection state of the injection pipe in the conventional scroll compressor,

2 is a longitudinal sectional view showing a part of the present invention scroll compressor;

3 is a perspective view of the compression unit broken in the scroll compressor according to FIG. 2;

4 is a longitudinal sectional view showing an enlarged back pressure passage in the scroll compressor according to FIG. 3;

5 and 6 are a perspective view and a longitudinal cross-sectional view showing an enlarged coupling state of the injection passage and the injection tube in the scroll compressor according to FIG.

7 is a system diagram showing a refrigeration cycle equipped with a scroll compressor of the present invention,

8 is a schematic view showing an embodiment of an air conditioner to which the scroll compressor according to FIG. 1 is applied.

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

1: scroll compressor 2: condenser

3: expander 4: evaporator

5: refrigerant tube 6: injection tube

7: bypass valve 10: casing

20: main frame 23: back pressure groove

40: fixed scroll 41: fixed scroll plate portion

42: fixed wrap 50: turning scroll

51: turning scroll plate 110: back pressure passage

111,112,113: Back pressure hole 114: Communication groove

115: blocking member 120: injection passage

121: first injection hole 122: second injection hole

131,132: first and second connector

Claims (11)

A casing having a closed inner space; A frame fixed to the inner space of the casing; A fixed scroll fixed to the frame; And Includes; the swing scroll to form a pair of compression chambers that are continuously moved while engaging the fixed scroll to the swing movement; An injection tube connected to a refrigerating cycle outside the casing for guiding a part of the refrigerant to the intermediate compression chamber is coupled to communicate with the compression chamber through the casing; And the injection tube is pressed into and coupled to the outer circumferential surface of the frame or the fixed scroll which is in close contact with the inner circumferential surface of the casing. The method of claim 1, The fixed scroll is formed with an injection passage penetrating from the compression chamber to the outer circumferential surface, the scroll compressor is coupled to the injection passage is pressed into the injection passage. The method of claim 2, The injection passage is press-fitted into the injection passage so that the outer circumferential surface of the injection passage extends from the inside of the injection passage to the outside of the casing, and the injection tube is inserted into the first connection tube to insert the first connection tube. Scroll compressors welded to the pipe. The method of claim 3, The first connecting pipe is a scroll compressor formed of the same material as the injection pipe. The method of claim 3, A second compressor is inserted and welded to the outer circumferential surface of the first connector, and the second connector is inserted into the casing and welded to the casing. The method of claim 1, And the injection passage is formed on both scrolls so as not to be larger than the thickness of the wrap forming the compression chamber. The method of claim 1, And the injection passage is formed to be stepped. The method of claim 1, And a back pressure chamber is formed on a rear surface of the swing scroll to accommodate the refrigerant bypassed from the compression chamber, and the fixed scroll further includes at least one bypass hole for communicating between the compression chamber and the back pressure chamber. The method of claim 8, And the bypass hole is formed closer to the suction side of the compression chamber than to the injection passage. 10. The method of claim 9, And the diameter of the bypass hole is not greater than the diameter of the injection 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 scroll compressor of any one of claims 1 to 11.

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