KR20050022697A - Capacity-Variable Type Rotary Compressor - Google Patents

Abstract

PURPOSE: A variable displacement rotary compressor is provided to prevent eccentric bushes from rotating at a speed faster than a rotary shaft at a specific interval, thereby preventing a noise generated due to slip between eccentric cams and eccentric bushes, and collision between a fixing pin of a rotary shaft and the eccentric bushes. CONSTITUTION: Upper and lower compression chambers are partitioned in different inner volume. A rotary shaft(21) passes through the upper and lower compression chambers. Upper and lower eccentric cams(41,42) are installed at the rotary shaft. Upper and lower eccentric bushes(51,52) are arranged on outer peripheral surfaces of the upper and lower eccentric cams. A slot(53) is formed between the upper eccentric bush and the lower eccentric bush. A fixing pin(83) acts with the slot for selectively converting the upper and lower eccentric bushes to a maximum eccentric position. A pocket part(81) is formed on the outer peripheral surface of the upper eccentric cam on the upward slant. A constraining pin(80) is installed inside the pocket part so that the constraining pin can roll. A plurality of constraining grooves(85,86) are formed horizontal to an inner peripheral surface of the upper eccentric bush.

Description

Capacity-variable rotary compressors {Capacity-Variable Type Rotary Compressor}

The present invention relates to a rotary compressor, and more particularly, to a rotary compressor capable of varying the capacity by selectively performing compression operation in any one of two compression chambers having different contents by an eccentric device disposed on the rotary shaft. will be.

A cooling device for cooling a specific space using a refrigeration cycle such as an air conditioner and a refrigerator is provided with a compressor for compressing a refrigerant circulating in a closed circuit of the refrigeration cycle. The cooling capacity of such a cooling device is usually determined according to the compression capacity of the compressor. Therefore, when the compressor is configured to vary the compression capacity of the compressor, the cooling device is optimally optimized according to the surrounding conditions such as the difference between the actual temperature and the set temperature. By operating in a state, it is possible to appropriately cool a specific space and at the same time save energy.

Compressors used in the cooling system include a rotary compressor and a reciprocating compressor, and the present applicant selectively compresses only one of two compression chambers having different contents through Korean Patent Application No. 10-2002-0061462. This has been applied for a variable displacement rotary compressor to vary the capacity.

In each compression chamber of the variable displacement rotary compressor, an eccentric device is arranged so that the compression operation is performed only in one compression chamber according to the rotation direction of the rotation shaft. The eccentric device includes two eccentric cams provided on the outer surface of the rotating shaft passing through the compression chambers, two eccentric bushes rotatably disposed on the outer surface of the eccentric cams, and rotatably disposed on the outer surface of the eccentric bushes. And two rollers for compressing the refrigerant gas, and a locking pin installed so that one eccentric bushing is shifted to an eccentric position with respect to the center line of the rotating shaft and the other eccentric bushing is shifted to a concentric position according to the direction in which the rotating shaft is rotated. It is configured to include.

Therefore, when the rotating shaft rotates in the forward or reverse direction, the compression operation is performed only in any one of the two compression chambers having different contents by the eccentric device configured as described above, thereby changing the capacity of the compressor.

However, such a capacity-variable rotary compressor has a structure in which each eccentric bush is engaged by a locking pin protruding from the rotary shaft in a state in which each eccentric bush is disposed on the outer circumferential surface thereof and rotates together with the rotary shaft. Due to the pressure change inside the compression chamber, the eccentric bushes rotate in a certain section faster than the rotational speed of the rotating shaft, causing slippage between each eccentric cam and the eccentric bush. There was a problem that the noise is generated by collision with the eccentric bush in the process of the pin is caught in the eccentric bush.

More specifically, in the slip phenomenon, a part of the compressed gas discharged to the discharge port is introduced into the compression chamber when the maximum eccentric portion of the eccentric bush disposed in the compression chamber where the compression action is performed passes between the discharge port and the vane provided in the compression chamber. In the process of reflow and re-expansion, the eccentric bush is applied in the rotational direction to rotate the eccentric bush at a faster speed than the corresponding eccentric cam, and the collision phenomenon occurs after the slip occurs. As it disappears, the locking pin of the rotating shaft is caused by hitting the eccentric bush again.

Conventional variable displacement rotary compressors are not only noise generated by the slip phenomenon and the collision phenomenon, but also wear or damage is generated in the impact portion is to reduce the reliability and durability.

The present invention is to solve the above-described problems of the prior art, an object of the present invention is due to the pressure change occurring in each compression chamber as the rotating shaft rotates in a certain section the eccentric bush rotates at a faster speed than the rotating shaft It is to provide a variable displacement rotary compressor to avoid.

Capacity variable rotary compressor according to the present invention for achieving this object,

Upper and lower compression chambers divided into different contents, rotation shafts penetrating the upper and lower compression chambers, upper and lower eccentric cams provided on the rotation shafts, and upper and lower circumferential surfaces of the upper and lower eccentric cams, respectively; A lower eccentric bush, a slot provided between the upper and lower eccentric bushes, a engaging pin for acting with the slot to selectively switch the upper and lower eccentric bushes to a maximum eccentric position, and an outer circumferential surface of the upper or lower eccentric cam A pocket portion formed to be inclined upwardly, a restraining pin embedded in the pocket portion so as to be movable in a cloud, and at least one restraint groove formed horizontally on an inner circumferential surface of the upper or lower eccentric bush to accommodate a portion of the restraining pin Characterized in that provided.

The restraint groove includes a first restraint groove which is in line with the pocket part when the upper eccentric bush is switched to the maximum eccentric position, and a second restraint which is in line with the pocket part when the lower eccentric bush is switched to the maximum eccentric position. The upper eccentric bush or the constraining groove is formed so that the constraining pin is clouded upward by the centrifugal force due to the rotation of the rotary shaft so that the constraining pin is disposed over the pocket part and the first constraining groove or the second constraining groove. This prevents slip rotation of the lower eccentric bush.

The restraint pin has a cylindrical shape, and the restraint pin and the first and second restraint grooves are elongated in the circumferential direction, so that the restraint pins are arranged in the circumferential direction with the planar portions at both ends of the restraint pin. By moving upward, the first or second restraint groove is caught.

Preferably, the depth of the pocket portion is greater than the diameter of the restraint pin, the depth of the first and second restraint groove is made smaller than the diameter of the restraint pin.

The locking pin protrudes from the rotary shaft between the upper eccentric cam and the lower eccentric cam, and the slot is formed between the upper eccentric bush and the lower eccentric bush to accommodate the locking pin, but the first end of the slot The second end is formed to have a length forming an angle of 180 degrees, the pocket portion and the first restraint groove are disposed so as to coincide with each other at a position where the engaging pin is caught in the first end of the slot, the pocket portion and the first The two restraint grooves are arranged to coincide with each other at a position where the catching pin is caught by the second end of the slot.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a longitudinal sectional view showing an approximate internal structure of a variable displacement rotary compressor according to the present invention. As shown therein, the variable displacement rotary compressor according to the present invention is installed in the sealed container 10 to generate a rotational force, and a compression unit for compressing gas by the rotational force of the drive unit 20. 30 is provided. The driving unit 20 includes a cylindrical stator 22 fixed to an inner surface of the sealed container 10, a rotor 23 rotatably installed in the stator 22, and the rotor 23. It is provided so as to extend from the center portion and is composed of a rotating shaft 21 which rotates forward (first rotation direction) or reverse rotation (second rotation direction) together with the rotor 23.

The compression unit 30 is disposed at the upper and lower ends of the housing 33 having a cylindrical upper compression chamber 31 and a lower compression chamber 32 having different contents in upper and lower portions, respectively. It is disposed between the upper flange 35 and the lower flange 36 to rotatably support the rotating shaft 21, and the upper compression chamber 31 and the lower compression chamber 32, the upper compression chamber 31 and the lower compression Intermediate plate 34 to allow the seals 32 to be partitioned from one another.

The height of the upper compression chamber 31 is formed larger than the height of the lower compression chamber 32 so that the contents of the upper compression chamber 31 are larger than the contents of the lower compression chamber 32, and thus the upper compression chamber ( 31, it is possible to compress the gas of a higher flow rate than the lower compression chamber 32, so that the rotary compressor according to the present invention has a variable capacity.

Of course, if the height of the lower compression chamber 32 is greater than the height of the upper compression chamber 31, the contents of the lower compression chamber 32 may be increased so that the gas in the lower compression chamber 32 can be compressed at a higher flow rate. It becomes larger than the content of the compression chamber 31.

The inside of the upper compression chamber 31 and the lower compression chamber 32 may be selectively compressed only in any one of the upper compression chamber 31 and the lower compression chamber 32 according to the rotational direction of the rotary shaft 21. An eccentric device 40 is disposed, and the eccentric device 40 is provided with a restraining device 80 for smooth operation without the slip rotation of the eccentric device 40, the eccentric device 40 ) And the structure and operation of the restraint device 80 will be described later with reference to FIGS. 2 to 10.

The upper compression chamber 31 and the lower compression chamber 32 are also provided with an upper roller 37 and a lower roller 38 rotatably disposed on the outer circumferential surface of the eccentric device 40, respectively, and in the housing 33. Upper and lower suction ports 63 and 64 and upper and lower discharge ports 65 and 66 (refer to FIGS. 3 and 7) are arranged to communicate with the upper compression chamber 31 and the lower compression chamber 32, respectively.

An upper vane 61 is radially disposed between the upper suction port 63 and the upper discharge port 65 in a state in which the upper vane 61 is in close contact with the upper roller 37 by the support spring 61a (see FIG. 3). Between the 64 and the lower discharge port 66, the lower vanes 62 are radially arranged in close contact with the lower roller 38 by the support spring 62a (see Fig. 7).

In addition, in the outlet tube 69a of the accumulator 69 which separates the liquid refrigerant and allows only the gas refrigerant to flow into the compressor, only the suction port side of the upper and lower suction inlets 63 and 64 formed in the housing 33 is compressed. A flow path switching device 70 for selectively opening and closing each suction flow path 67 and 68 so that a gas refrigerant is supplied is provided. The suction flow paths 67 and 68 are formed inside the flow path switching device 70 by the pressure difference between the suction flow path 67 connected to the upper suction port 63 and the suction flow path 68 connected to the lower suction port 64. The valve device 71 which opens only one of them and is supplied with the refrigerant gas is arranged to be movable left and right.

Next will be described with reference to Figure 2 the structure of the rotating shaft and the eccentric device which constitutes a characteristic configuration of the present invention.

Figure 2 is a perspective view showing a state in which the eccentric device of the present invention is separated from the rotating shaft. As shown therein, the eccentric device 40 has an upper eccentric cam 41 and a lower eccentric cam 42 provided at positions corresponding to the upper compression chamber 31 and the lower compression chamber 32, respectively, on the rotation shaft 21. Between the upper eccentric bush 51 and the lower eccentric bush 52, the upper eccentric cam 41 and the lower eccentric cam 42, which are disposed on the outer circumferential surfaces of the upper eccentric cam 41 and the lower eccentric cam 42, respectively. Installed locking pin 43, a slot 53 provided with a predetermined length between the upper eccentric bush 51 and the lower eccentric bush 52 so that the locking pin 43 is caught, and the upper eccentric bush 51 and the lower eccentric The bush 52 is provided with a restraining device 80 to restrain the slip rotation of the upper eccentric cam 41 and the lower eccentric cam 42, respectively, in a particular section.

The upper eccentric cam 41 and the lower eccentric cam 42 protrude integrally in the transverse direction from the outer circumferential surface of the rotating shaft 21 and are vertically disposed in an eccentric state with respect to the center line C1-C1 of the rotating shaft 21. In addition, the upper and lower eccentric cams (41, 42) are each projected to the maximum from the upper and lower eccentric cams 41, 42 of the upper and lower eccentric cams (41) 42 and the uppermost projecting to the minimum. And an upper eccentric line L1-L1 and a lower eccentric line L2-L2 connecting the minimum eccentric portions of the lower eccentric cams 41 and 42.

The locking pin 43 is composed of a threaded body 44 and a head 45 formed with a diameter slightly larger than the body 44 at the tip of the body 44, the upper eccentric cam 41 The body portion (3) in a screw hole (46) formed at a position to form an approximately 90 degree angle with the eccentric lines (L1-L1) (L2-L2) on the rotation shaft (21) between the lower eccentric cam (42). 44 is screwed to the rotary shaft 21 is fastened.

The upper eccentric bushes 51 and the lower eccentric bushes 52 are integrally formed by connecting parts 54 connecting them, and have a width slightly larger than the diameter of the head 45 of the locking pin 43. The slot 53 having the circumferential direction is formed in the connecting portion 54.

Therefore, the upper eccentric bush 51 and the lower eccentric bush 52 formed integrally connected by the connecting portion 54 are inserted into the rotating shaft 21, and the locking pin 43 is rotated through the slot 53. When fastened to the screw hole 46 of the locking pin 43 is installed in the rotating shaft 21 in the state fitted to the slot (53).

In this state, when the rotating shaft 21 is rotated forward or reverse, the upper and lower portions thereof until the engaging pin 43 is caught by any one of the first end 53a and the second end 53b of the slot 53. The eccentric bushes 51 and 52 do not rotate, and when the engaging pin 43 is caught by the first end 53a or the second end 53b, the upper eccentric bushes 51 and the lower eccentric bushes 52 The rotating shaft 21 is rotated forward or reverse.

On the other hand, the angle between the eccentric line (L3-L3) connecting the maximum eccentric portion and the minimum eccentric portion of the upper eccentric bush (51) and the line connecting the center of the first end (53a) of the slot 53 and the connecting portion (54) Is formed to form approximately 90 degrees, the eccentric line (L4-L4) and the second end (53b) of the slot 53 and the connecting portion (54) connecting the maximum eccentric portion and the minimum eccentric portion of the lower eccentric bush (52) The angle between the lines connecting the center is likewise formed to be approximately 90 degrees.

In addition, the eccentric line (L3-L3) of the upper eccentric bush (51) and the eccentric line (L4-L4) of the lower eccentric bush (52) are located on the same plane, but the maximum eccentric portion of the upper eccentric bush (51) and The maximum eccentric portions of the lower eccentric bush 52 are eccentrically disposed to face opposite sides, and connect the first end 53a and the second end 53b of the slot 53 formed in the circumferential direction to the connecting portion 54. The line is formed to form an angle of 180 degrees.

In the eccentric device 40 configured as described above, the restraining device 80 is provided over the upper eccentric cam 41 and the upper eccentric bush 51. That is, the restraint device 80 according to the present invention has a pocket portion 81 formed in a groove with a predetermined length and a predetermined depth on the outer circumferential surface of the upper eccentric cam 41, and the pocket portion on the inner circumferential surface of the upper eccentric bush 51. The first restraint groove 85 and the second restraint groove 86 formed to have the same length and smaller depth as the 81, and have a length slightly smaller than the length of the pocket portion 81, so that the cloud portion is formed in the pocket portion 81. The movement is provided with a restraining pin 83 freely embedded.

The pocket portion 81 is formed along the outer circumferential surface of the upper eccentric cam 41 along the circumferential direction and is inclined upwardly at an angle from the inner side of the upper eccentric cam 41 to the outer side. The second restraint grooves 85 and 86 are formed in the same length as the pocket portion 81 along the circumferential direction on the inner circumferential surface of the upper eccentric bush 51 and are arranged horizontally.

The restraint pin 83 is formed in a cylindrical shape with a predetermined diameter and length so that both ends 83a form a plane. The length of the restraint pin 83 is slightly smaller than the length of the pocket portion 81 and the first and second restraint grooves 85 and 86, and the depth of the pocket portion 81 is the restraint pin 83. ) Is formed larger than the diameter, the depth of the first and second restraint grooves (85, 86) is formed smaller than the diameter of the restraint pin (83).

Therefore, the restraint pin 83 is placed at the lower end of the pocket portion 81 inclined upwardly by gravity in the state in which the rotating shaft 21 is stopped, and at the same time, both side ends 83a are pocket portions 81. If the rotating shaft 21 is rotated at a predetermined speed or more in the first or second direction in a state that the rotating shaft 21 is not constrained the upper and lower eccentric bushes 51 and 52 in the circumferential direction. The upper or lower eccentric bushes 51 and 52 are rotated in a state of being restrained by the rotation shaft 21 while being partially rolled on the first or second restraint grooves 85 and 86 by rolling or sliding. will be.

Here, in the exemplary embodiment of the present invention, the pocket portion 81 and the first and second restraint grooves 85 and 86 are illustrated as being provided in the upper eccentric cam 41 and the upper eccentric bush 51, respectively. Even if the pocket portion 81 (and the first and second restraint grooves 85 and 86) are provided in the lower eccentric cam 42 and the lower eccentric bush 52, respectively, the same effect can be obtained. .

In the pocket portion 81 and the first restraint groove 85, the locking pin 43 is caught by the first end 53a of the slot 53 so that the upper eccentric cam 41 and the upper eccentric bush 51 are the maximum. In the eccentric state to form a line to each other.

That is, on the basis of the case in which the rotating shaft 21 rotates in the first rotation direction (counterclockwise in FIG. 2), the pocket portion 81 is disposed to be formed at a position that is behind the locking pin 43 at an angle of 90 degrees. And, the first restraint groove 85 is disposed so as to be formed at a position that is behind the first end (53a) of the slot 53 at an angle of 90 degrees, so that the locking pin 43 is the first end of the slot ( 53a), the pocket 81 collides with the first restraint groove 85 in a state where the rotating shaft 21 is rotated in the first rotation direction together with the upper and lower eccentric bushes 51 and 52. To make it possible.

In addition, the second restraint groove 86 is formed at a position opposite to the first restraint groove 85 in the upper eccentric bush 51, that is, at a position that forms an angle of 180 degrees with the first restraint groove 85. When the rotating shaft 21 is rotated in the second rotation direction and the locking pin 43 is caught by the second end 53b of the slot 53, the pocket 81 is rotated 180 degrees such that the second restraint groove ( 86) to be aligned in line with.

The locking pin 43 is caught by the first end 53a of the slot 53 by the arrangement structure as described above, so that the upper eccentric bush 51 rotates in the first rotation direction together with the rotation shaft 21 (of course, the lower portion). The eccentric bush is rotated together with the upper eccentric bush 51 at each position where the eccentric bush 51 rotates together with the maximum eccentric portion of the upper eccentric bush 41 and the maximum eccentric bush of the upper eccentric bush 51. While rotating forward with the maximum eccentricity (see FIG. 3), the lower eccentric bush 52 has the maximum eccentric portion of the lower eccentric cam 42 and the minimum eccentric portion of the lower eccentric bush 52 abut on each other. Forward rotation is made in concentric with (21) (see Fig. 4).

At this time, while the pocket 81 is in line with the first restraint groove 85, the restraint pin 83 is clouded toward the first restraint groove 85 by centrifugal force, so that the pocket part 81 and the first restraint. The upper eccentric cam 41 and the upper eccentric bush 51 are restrained from each other by being disposed over the restriction groove 85.

By the above operation, the upper eccentric bush 51 can be prevented from being slip-rotated from the upper eccentric cam 41 in a specific section when the rotating shaft rotates in the first rotation direction.

Contrary to the above, the lower eccentric at the angular position where the engaging pin 43 is caught by the second end 53b of the slot 53 so that the lower eccentric bush 52 rotates in the second rotation direction together with the rotation shaft 21. While the bush 52 rotates in a state where the maximum eccentric portion of the lower eccentric cam 42 and the maximum eccentric portion of the lower eccentric bush 52 abut each other and are eccentrically with the rotation shaft 21 (FIG. 7). The upper eccentric bush 51 is reversely rotated in a state in which the maximum eccentric portion of the upper eccentric cam 41 and the minimum eccentric portion of the upper eccentric bush 51 abut on each other and are concentric with the rotating shaft (see FIG. 8). ).

At this time, while the pocket 81 is in line with the second restraint groove 86, the restraint pin 83 is clouded toward the second restraint groove 86 by centrifugal force, so that the pocket part 81 and the second restraint. The upper eccentric cam 41 and the upper eccentric bush 51 are constrained to each other by being disposed over the constraining grooves 86, and the lower eccentric bush 52 in a specific section when the rotating shaft rotates in the second rotation direction by this operation. ) Can be prevented from slip rotation from the lower eccentric cam (42).

Hereinafter, an operation of selectively compressing refrigerant gas in the upper compression chamber or the lower compression chamber by the eccentric device configured as described above with reference to FIGS. 3 to 10 will be described.

3 is a view showing that the compression operation is performed in a state that the rotation axis is rotated in the first rotation direction in the upper compression chamber by the eccentric apparatus according to the present invention does not occur, Figure 4 is a view corresponding to FIG. , The rotating shaft is rotated in the first direction of rotation and thus the compression action is not performed in the lower compression chamber by the eccentric apparatus according to the present invention, and FIG. 5 shows the rotation axis in the first direction of rotation according to the present invention. A cross-sectional view taken along the line AA of FIG. 2 to show that slipping of the upper rotary bushing does not occur in a particular section by the eccentric device, and FIG. 6 is a cross-sectional view taken along the line BB of FIG.

As shown in FIG. 3, the engaging pin 43 protruding from the rotating shaft 21 by rotating the rotation shaft 21 in the first rotation direction (counterclockwise in FIG. 3) is provided with the upper eccentric bush 51 and the lower eccentric. When the locking pin 43 is caught by the first end 53a of the slot 53 when the locking pin 43 is rotated at a predetermined angle while being inserted into the slot 53 formed between the bushes 52, the upper eccentric bush 51 is rotated 21. Will rotate). At this time, since the lower eccentric bush 52 is also formed integrally connected with the upper eccentric bush 51 by the connecting portion 54, the lower eccentric bush 52 rotates integrally with the upper eccentric bush 51.

In the state where the locking pin 43 is engaged with the first end 53a of the slot 53, as described above, the maximum eccentric portion of the upper eccentric cam 41 is brought into contact with the maximum eccentric portion of the upper eccentric bush 51. The upper eccentric bush 51 is rotated in a state in which the upper eccentric bush 51 is switched to the maximum eccentric position with respect to the center line C1-C1 of the rotation shaft 21, whereby the upper roller 37 forms the upper compression chamber 31. The compression operation is performed while rotating in contact with the inner circumferential surface of the housing 33.

In addition, the pocket portion 81 of the restraint device 80 and the first restraint groove 85 coincide with each other so that the restraint pins 83 extend between the pocket part 81 and the first restraint groove 85 by centrifugal force. It is disposed in the circumferential direction in a state to rotate while maintaining the upper eccentric cam 41 and the upper eccentric bush 51 in a state constrained with each other.

At the same time, as shown in FIG. 4, the maximum eccentric portion of the lower eccentric cam 42 abuts the minimum eccentric portion of the lower eccentric bush 52 such that the lower eccentric bush 52 is the centerline C1- of the rotation shaft 21. It rotates while being switched to the concentric position with respect to C1), and thus the lower roller 38 is rotated while being spaced at regular intervals from the inner peripheral surface of the housing 33 forming the lower compression chamber 32 Compression will not work.

Therefore, when the rotating shaft 21 rotates in the first rotation direction, the refrigerant gas introduced into the upper suction port 63 by the upper roller 37 is compressed in the upper compression chamber 31 having a relatively high content, and thus the upper discharge port 65. In the lower compression chamber 32, which is relatively small in content, the compression operation is not performed, so that the rotary compressor operates in a state where the compression capacity is large.

On the other hand, as shown in Figure 3, the upper roller 37 is in contact with the upper vane 61 to complete the compression operation of the refrigerant gas and at the same time when the suction operation of the refrigerant gas to the upper discharge port 65 Some of the compressed gas that could not escape through the flow back into the upper compression chamber 31 is re-expanded and the pressure is applied to the upper roller 37 and the upper eccentric bush 51 in the direction in which the rotating shaft 21 rotates. As the upper eccentric bush 51 is rotated at a faster speed than the rotation shaft 21, a slip phenomenon occurs in which the upper eccentric bush 51 slips from the upper eccentric cam 41.

In addition, when the rotation shaft 21 is further rotated in the above state, the locking pin 43 collides with the first end 53a of the slot 53 while the upper eccentric bush 51 is coupled with the rotation shaft 21. It will rotate at the same speed, which will generate noise and damage the contact area.

However, the eccentric device 40 according to the present invention is provided with the above-mentioned restraining device 80 to suppress the slip rotation of the upper eccentric bush 51.

That is, in the rotational position where the upper roller 37 is in contact with the upper vane 61, the upper eccentric bush 51 is caused by a gas pressure generated when a part of the refrigerant gas flows back from the upper discharge port 65 to re-expand. Force acts in the direction in which the rotating shaft 21 rotates (first rotation direction), thereby causing a slip phenomenon in the upper eccentric bush 51, but as shown in FIGS. 5 and 6, the restraining pin 83 has a centrifugal force. By rolling or sliding to the upper portion of the pocket 81 by being positioned over the pocket 81 and the first restraint groove 85, both ends (83a) of the restraining pin (83) forming a plane is a plane The upper eccentric cam 41 is rotated in a state in which the upper eccentric cam 41 is restrained from each other by being caught by both ends of the pocket portion 81 and the first restraint groove 85 that form the upper eccentric bush ( 51 to rotate at the same speed as the upper eccentric cam 41 without slip rotation to be.

On the other hand, when the rotation of the rotating shaft 21 is stopped, the centrifugal force no longer acts on the restraint pins 83, so that the restraint pins 83 roll or slide down the pocket portion 81 inclined by gravity again. The locking pin 43 is caught by the second end 53b of the slot 53 when the rotating shaft 21 rotates in the second rotation direction while releasing the restraint of the first constraining groove 85. In (32), a compression operation can be performed, which will be described next.

7 is a view showing that the compression operation is performed in a state that the slip shaft is not generated in the lower compression chamber by the eccentric device according to the present invention by rotating the rotation axis in the second rotation direction, Figure 8 is a view corresponding to FIG. The rotating shaft is rotated in the second rotation direction is a view showing that the compression action is not performed in the upper compression chamber by the eccentric apparatus according to the present invention, Figure 9 is the eccentric apparatus according to the present invention when the rotating shaft rotates in two directions This is a cross-sectional view taken along the line AA of FIG. 2 to show that the slip phenomenon of the lower rotating bush is not generated in a particular section, Figure 10 is a cross-sectional view taken along the line CC of FIG.

As shown in FIG. 7, when the rotation shaft 21 rotates in the second rotation direction (clockwise in FIG. 7), the compression operation is performed only in the upper compression chamber 31 as in FIGS. 3 and 4. In operation, the compression is performed only in the lower compression chamber 32.

That is, the locking pin 43 protruding from the rotary shaft 21 is caught by the second end 53b of the slot 53 by the rotation of the rotary shaft 21 in the second rotation direction, thereby lowering the eccentric bush 52. And the upper eccentric bush 51 are rotated in the second rotation direction by the rotation shaft 21.

This switching operation causes the maximum eccentric portion of the lower eccentric cam 42 to contact the maximum eccentric portion of the lower eccentric bush 52 so that the lower eccentric bush 52 is maximum with respect to the center line C1-C1 of the rotation shaft 21. It is converted to the eccentric state and rotated, so that the lower roller 38 is rotated in contact with the inner circumferential surface of the housing 33 forming the lower compression chamber 32 to perform the compression operation.

In addition, the pocket portion 81 of the upper eccentric cam 41 is positioned to coincide with the second restraint groove 86 of the upper eccentric bush 51 such that the restraining pin 83 embedded in the pocket portion 81 is subjected to centrifugal force. As a result of the rolling or sliding movement toward the second restraint groove 86, it is positioned over the pocket portion 81 and the second restraint groove 86.

At the same time, as shown in FIG. 8, the maximum eccentric portion of the upper eccentric cam 41 abuts against the minimum eccentric portion of the upper eccentric bush 51 such that the upper eccentric bush 51 is the centerline C1- of the rotation shaft 21. It is converted into a concentric state with respect to C1) and rotates, so that the upper roller 37 rotates while being spaced at a predetermined interval from the inner circumferential surface of the housing 33 forming the upper compression chamber 31. This will not be done.

Therefore, in the lower compression chamber 32 having a relatively small inner content, the refrigerant gas introduced into the lower suction port 64 by the lower roller 38 is compressed and discharged through the lower discharge port 66. Since the compression operation is not performed in the compression chamber 31, the rotary compressor is operated in a state where the compression capacity is small.

On the other hand, as shown in Figure 7, the lower roller 38 abuts the lower vanes 62 to complete the compression operation of the refrigerant gas and at the same time when the suction operation of the refrigerant gas to the lower discharge port 66 Some of the compressed gas that could not escape through the flow back into the lower compression chamber 32 is re-expanded and the pressure is applied to the lower roller 38 and the lower eccentric bush 52 in the direction in which the rotating shaft 21 rotates. As a result, the lower eccentric bush 52 rotates at a higher speed than the rotation shaft 21, thereby causing a slip phenomenon in which the lower eccentric bush 52 slides from the lower eccentric cam 42.

In addition, when the rotating shaft 21 is further rotated in the above state, the locking pin 43 collides with the second end 53b of the slot 53 while the lower eccentric bush 52 is connected to the rotating shaft 21. It will rotate at the same speed, and there is a possibility that noise will be generated during this collision and damage will occur at the collision site.

However, the slip phenomenon and the collision phenomenon as described above do not occur because the restraint device 80 according to the present invention restrains the upper eccentric bush 51 similarly to when the rotating shaft 21 rotates in the first rotation direction. .

That is, in the rotational position where the lower roller 38 is in contact with the lower vane 62, the lower eccentric bush 52 is caused by the gas pressure generated when a part of the refrigerant gas flows back and expands from the lower discharge port 66. Force acts in the direction in which the rotating shaft 21 rotates (second rotation direction), thereby causing a slip phenomenon in the lower eccentric bush 52. However, as shown in FIGS. 9 and 10, the restraining pin 83 has a centrifugal force. By rolling or sliding to the upper portion of the pocket 81 by being positioned over the pocket 81 and the second restraint groove 86, both ends (83a) of the restraining pins 83 forming a plane is a plane The upper eccentric cam 41 is rotated in a state in which the upper eccentric cam 41 is restrained from each other by being caught by both ends of the pocket portion 81 and the first restraint groove 82, thereby forming a lower eccentric bush ( 51 is rotated at the same speed as the lower eccentric cam 41 without slip rotation A.

On the other hand, when the rotation of the rotating shaft 21 is stopped, the centrifugal force no longer acts on the restraint pins 83, so that the restraint pins 83 roll or slide down the pocket portion 81 inclined by gravity again. The locking pin 43 is caught by the first end 53a of the slot 53 when the rotating shaft 21 rotates in the first rotation direction while releasing the restraint of the second restraint groove 86. In (32), compression can be achieved.

As described in detail above, the capacity-variable rotary compressor according to the present invention has a structure capable of varying the compression capacity by the eccentric device which rotates in the forward or reverse direction in the upper compression chamber and the lower compression chamber having different contents, the surrounding space In addition to being able to cool properly, there is an effect that can save energy.

In particular, the variable displacement compressor according to the present invention is the upper eccentric bushing due to the pressure change in the upper or lower compression chamber during the rotation of the eccentric device in the forward or reverse direction by the restraining device provided over the upper eccentric cam and the upper eccentric bush. Alternatively, the phenomenon in which the lower eccentric bush is not slipped does not occur so that the upper and lower eccentric bushes rotate smoothly.

1 is a longitudinal sectional view showing an approximate internal structure of a variable displacement rotary compressor according to the present invention.

2 is a perspective view showing a state in which the eccentric device according to the present invention is separated from the rotating shaft.

3 is a view showing that the compression operation is performed in a state that the slip shaft does not occur in the upper compression chamber by the eccentric apparatus according to the present invention by rotating the rotary shaft in the first rotation direction.

FIG. 4 is a view corresponding to FIG. 3, in which a rotation axis rotates in a first rotation direction, and thus a compression action is not performed in the lower compression chamber by the eccentric apparatus according to the present invention.

FIG. 5 is a cross-sectional view taken along the line A-A of FIG. 2 to show that the slip phenomenon of the upper rotating bush does not occur in a specific section by the eccentric device according to the present invention when the rotating shaft rotates in the first rotation direction.

FIG. 6 is a cross-sectional view taken along the line B-B of FIG. 5.

7 is a view showing that the compression operation is performed in a state in which the slip does not occur in the lower compression chamber by the eccentric apparatus according to the present invention by rotating the rotation axis in the second rotation direction.

FIG. 8 is a view corresponding to FIG. 7, in which the rotating shaft rotates in the second rotation direction, and thus the compression operation is not performed in the upper compression chamber by the eccentric apparatus according to the present invention.

FIG. 9 is a cross-sectional view taken along the line A-A of FIG. 2 to show that the slip phenomenon of the lower rotating bush does not occur in a specific section by the eccentric device according to the present invention when the rotating shaft rotates in two directions.

FIG. 10 is a cross-sectional view taken along the line C-C of FIG. 9.

* Description of symbols on the main parts of the drawings

21: rotating shaft 31: upper compression chamber

32: lower compression chamber 40: eccentric device

41: upper eccentric cam 42: lower eccentric cam

43: engaging pin 51: upper eccentric bush

52: lower eccentric bush 53: slot

80: restraining device 81: pocket

83: restraint pin 85: first restraint groove

86: second restraint groove

Claims (7)

Upper and lower compression chambers divided into different contents, rotation shafts penetrating the upper and lower compression chambers, upper and lower eccentric cams provided on the rotation shafts, and upper and lower circumferential surfaces of the upper and lower eccentric cams, respectively; A lower eccentric bush, a slot provided between the upper and lower eccentric bushes, a engaging pin for acting with the slot to selectively switch the upper and lower eccentric bushes to a maximum eccentric position, and an outer circumferential surface of the upper or lower eccentric cam A pocket portion formed to be inclined upwardly, a restraining pin embedded in the pocket portion so as to be movable in a cloud, and at least one restraint groove formed horizontally on an inner circumferential surface of the upper or lower eccentric bush to accommodate a portion of the restraining pin Capacity variable rotary compressor, characterized in that consisting of. 2. The constraining groove of claim 1, wherein the constraining groove includes a first constraining groove which is aligned with the pocket portion when the upper eccentric bushing is switched to the maximum eccentric position, and the pocket portion when the lower eccentric bushing is switched to the maximum eccentric position. Comprising a second constrained groove formed in a line with the constrained pin, the constraining pin is rolled upward by the centrifugal force according to the rotation of the rotary shaft to be disposed across the pocket portion and the first constrained groove or the second constrained groove. The variable displacement rotary compressor characterized in that it prevents the slip rotation of the upper eccentric bush or the lower eccentric bush. The constraining pin of claim 2, wherein the constraining pin has a cylindrical shape, and the constraining pin and the first and second constraining grooves are elongated in the circumferential direction, so that the constraining pin has a flat portion at both ends of the constraining portion in the pocket portion. The variable displacement rotary compressor characterized in that it is caught in the first or second restraint groove by moving upward in the state arranged in the direction. 4. The variable displacement rotary compressor of claim 3, wherein a depth of the pocket part is larger than a diameter of the restraint pin, and a depth of the first and second restraint grooves is smaller than a diameter of the restraint pin. The locking pin of claim 2, wherein the locking pin protrudes from the rotation shaft between the upper eccentric cam and the lower eccentric cam, and the slot is formed between the upper eccentric bush and the lower eccentric bush to accommodate the locking pin. The first end and the second end of the slot are formed to have a length forming an angle of 180 degrees, the pocket portion and the first restraint groove are disposed so as to coincide with each other at the position where the engaging pin is caught in the first end of the slot, And the pocket part and the second constraining groove are arranged to coincide with each other at a position where the locking pin is caught by the second end of the slot. The variable displacement rotary compressor of claim 1, wherein the first and second restraint grooves are provided on an inner circumferential surface of the upper eccentric bush. The capacity variable rotary compressor of claim 1, wherein the first and second restraint grooves are provided on an inner circumferential surface of the lower eccentric bush.