JP2007205211A - Two cylinder type rotary compressor and refrigeration cycle device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two cylinder type rotary compressor capable of increasing work done per unit time as a compressor and improving performance and reliability as the compressor. <P>SOLUTION: In the two cylinder type rotary compressor having a motor part, a rotary shaft 10 including two eccentric parts 14, 15 formed on a position shifted by 180 degrees around a rotation center and connected to the motor part, and two compression mechanism parts driven by rotation of the rotary shaft 10 around the rotation center stored in a sealed case, the compression mechanism part includes rollers 21, 23 attached on the eccentric parts 14, 15 via ball bearings 20, 22, and satisfies a relation Hr>Lh>Hb when axial direction height dimension of the rollers 21, 23 is defined as Hr, axial direction height dimension of the ball bearings 20, 22 is defined as Hb and length dimension of a connecting part 10c connecting two eccentric parts 14, 15 of the rotary shaft 10 is defined as Lk. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a two-cylinder rotary compressor and a refrigeration cycle apparatus, and more particularly to a two-cylinder rotary compressor capable of improving compression performance and a refrigeration cycle apparatus using the two-cylinder rotary compressor. About.

  For example, as described in Patent Document 1 below, a two-cylinder rotary compressor having two compression mechanisms is known.

  Such a two-cylinder rotary compressor has a rotating shaft that is housed in a hermetically sealed case and is driven to rotate by an electric motor unit, and the rotating shaft has two eccentric positions shifted by 180 degrees with respect to the rotation center. And has two compression mechanisms each having a roller fitted to each eccentric portion. The compression mechanism section is formed by a roller, a cylinder that stores the roller, and the like.

  When the rotating shaft is driven to rotate around the center of rotation, the roller rotates eccentrically in the cylinder, and the refrigerant gas is compressed in a compression chamber formed between the inner peripheral surface of the cylinder and the outer peripheral surface of the roller. The compressed refrigerant gas is sent to the evaporator via the condenser and used for refrigeration or cooling.

  FIG. 4 shows a rotating shaft 100, two eccentric portions 101a and 101b formed on the rotating shaft 100, and rollers 102a and 102b fitted to the eccentric portions 101a and 101b in the two-cylinder rotary compressor. ing.

  FIG. 5 is a process diagram for explaining a process when the rollers 102a and 102b are fitted to the eccentric parts 101a and 101b. In this step, the roller 102a is fitted to the eccentric portion 101a, and then the roller 102b is fitted to the eccentric portion 101b.

  FIG. 5A shows a state in which the roller 102a is inserted from the end of the rotating shaft 100 where the eccentric portion 101b is formed, and the roller 102a is fitted to the outer periphery of the eccentric portion 101b.

  FIG. 5B shows a state in which the roller 102a is passed through the outer peripheral portion of the eccentric portion 101b and is advanced to the outer peripheral portion of the connecting portion 100a connecting the two eccentric portions 101a and 101b of the rotating shaft 100. The upper end surface of the roller 102a is in contact with the lower end surface of the eccentric portion 101a.

  5C, the roller 102a is moved in the left direction orthogonal to the direction of the rotation center “A” of the rotary shaft 100, and the roller 102a is positioned at a position where the roller 102a can be fitted to the outer peripheral portion of the eccentric portion 101a. State.

  FIG. 5D shows a state in which the roller 102a is moved in the direction of the rotation center “A” of the rotary shaft 100 and fitted to the outer peripheral portion of the eccentric portion 101a.

As shown in FIG. 5D, after the roller 102a is fitted to the eccentric portion 101a, the roller 102b is fitted to the eccentric portion 101b, whereby the state shown in FIG. 4 is obtained.
JP 2003-328972 A

  However, in the above-described two-cylinder rotary compressor, the following points are not considered.

  When the length dimension of the connecting portion 100a is L1 and the height dimension of the roller 102a is L2, it is necessary to satisfy L1> L2 in order to enable the state of FIG. That is, the length of the connecting portion 100a needs to be larger than the height of the roller 102a.

  Here, the rotating shaft 100 rotates while being supported by a bearing at a position between the two eccentric portions 101a and 101b and the connecting portion 100a, and the connecting portion 100a bends during this rotation. If bending occurs in the connecting portion 100a, vibration occurs during rotation, or the contact state between the outer peripheral surface of the rollers 102a and 102 and the inner peripheral surface of the cylinder becomes unstable, and the performance and reliability as a compressor are improved. descend.

  For this reason, in order to improve the performance and reliability as a compressor, it is desirable to reduce the length of the connecting portion 100a as much as possible to reduce the amount of bending of the connecting portion 100a when the rotating shaft 100 rotates. If attention is paid only to the point that the length L1 of the connecting portion 100a is reduced, the height L2 of the roller 102a may be reduced. However, when the height L2 of the roller 102a is reduced, the volume in the compression chamber formed between the inner peripheral surface of the cylinder and the outer peripheral surface of the roller 102a is reduced, and the work per unit time as a compressor is reduced. descend.

  That is, in order to increase the amount of work per unit time as a compressor, the height dimension L2 of the roller 102a is increased, and in order to reduce the amount of bending at the connecting portion 100a when the rotary shaft 100 rotates. It cannot be satisfied at the same time to reduce the length of the connecting portion 100a.

  The present invention has been made in order to solve such problems, and an object of the present invention is to increase the work per unit time as a compressor and improve the performance and reliability as a compressor. It is to provide a two-cylinder type rotary compressor that can be used and a refrigeration cycle apparatus using the two-cylinder type rotary compressor.

  A first feature according to an embodiment of the present invention is that an electric motor unit and a rotating shaft coupled to the electric motor unit having two eccentric parts formed at positions shifted by 180 degrees with respect to the rotation center A two-cylinder rotary compressor in which two compression mechanism parts driven by rotation of the rotary shaft about the rotation center are housed in a sealed case, wherein the compression mechanism part is the eccentric part. The roller has a roller mounted via a ball bearing, the height of the roller in the axial direction is Hr, the height of the ball bearing in the axial direction is Hb, and the gap between the two eccentric portions of the rotary shaft is between That is, when the length dimension of the connecting portion to be connected is Lk, the relationship is Hr> Lk> Hb.

  According to a second aspect of the present invention, in the refrigeration cycle apparatus, the two-cylinder rotary compressor according to any one of claims 1 to 3 and the two-cylinder rotary compressor are connected. A condenser, an expansion device connected to the condenser, and an evaporator connected to the expansion device.

  According to the present invention, the amount of work per unit time as a compressor can be increased, and the performance and reliability as a compressor can be improved.

  An embodiment of the present invention will be described below with reference to FIGS.

  As shown in FIG. 1, the refrigeration cycle apparatus according to an embodiment of the present invention includes a two-cylinder rotary compressor 1, a condenser 2, an expansion device 3, an evaporator 4, and an accumulator 5. It is connected via a refrigerant transport pipe.

  As will be described later, the two-cylinder rotary compressor 1 has an electric motor unit, a rotating shaft, and a compression mechanism unit, and is a device that compresses a gaseous refrigerant to a high temperature and a high pressure. The gaseous refrigerant that has become high temperature and high pressure is supplied to the condenser 2.

  The condenser 2 is a device that cools the refrigerant that has become a high temperature and a high pressure by being compressed in the two-cylinder rotary compressor 1 to remove heat and liquefy it. As a method of cooling the refrigerant, for example, a method of blowing air by driving a fan can be employed.

  The expansion device 3 is a device that injects a liquid refrigerant from a minute nozzle hole to form a low-temperature and low-pressure refrigerant.

  The evaporator 4 is a device that vaporizes the refrigerant. When the refrigerant evaporates, the refrigerant takes heat from the surroundings, and the surrounding air is cooled. In this case, cool air is generated by driving the fan toward the evaporator 4 and blowing air, and the generated cool air is used for freezing or cooling.

  The accumulator 5 is a device that separates the refrigerant that has passed through the evaporator 4 into a gas refrigerant and a liquid refrigerant. The gas refrigerant separated by the accumulator 5 is supplied to the two-cylinder rotary compressor 1 via a suction pipe 6 that is a refrigerant transport pipe.

  Next, the structure of the two-cylinder rotary compressor 1 will be described.

  The two-cylinder rotary compressor 1 is housed in a hermetic case 8 having a discharge pipe 7 that is a refrigerant transport pipe connected to the condenser 2 and a suction pipe 6 that is connected to the accumulator 5. The motor section 9, the rotating shaft 10, and the two compression mechanism sections 11 and 12 are provided. Lubricating oil 13 is stored on the bottom side in the sealed case 8.

  The electric motor unit 9 is a mechanism that rotates the rotating shaft 10 around the rotation center “A” when energized. For example, a rotation that includes a stator that is fixed to the inner peripheral surface of the sealed case 8 and that is supplied with electric power from the outside, and a magnet that is fixed to the rotating shaft 10 and disposed with a predetermined gap dimension between the stator and the stator. It is formed by a child or the like.

  Two eccentric portions 14 and 15 are formed on the rotation shaft 10 at positions shifted by 180 degrees with respect to the rotation center “A”. A portion of the rotating shaft 10 closer to the motor unit 9 than the eccentric portion 14 (a portion above the eccentric portion 14) is the main shaft portion 10a, and a portion on the end side below the eccentric portion 15 is the subshaft portion 10b. Yes. The part between the eccentric parts 14 and 15 in the rotating shaft 10 is a connecting part 10c that connects the two eccentric parts 14 and 15 and connects them.

  The main shaft portion 10 a is pivotally supported by a main bearing 17 via a pair of ball bearings 16, and the subshaft portion 10 b is pivotally supported by a sub bearing 19 via a ball bearing 18. The diameter of the main shaft portion 10a is “φDm”, the diameter of the auxiliary shaft portion 10b is “φDs”, and φDm> φDs.

  A roller 21 is fitted to the eccentric portion 14 via a ball bearing 20. A roller 23 is fitted to the eccentric portion 15 via a ball bearing 22. A cylinder 24 is disposed on the outer periphery of the roller 21, a cylinder 25 is disposed on the outer periphery of the roller 23, and a partition plate 26 is disposed between the cylinder 24 and the cylinder 25.

  One compression mechanism 11 includes a cylinder 24, a main bearing 17 and a partition plate 26 that are disposed at positions that close both ends of the cylinder 24 along the rotation center “A” direction of the rotary shaft 10, and these cylinders 24. And a roller 21 that rotates eccentrically in the compression chamber 27 surrounded by the main bearing 17 and the partition plate 26. The suction pipe 6 is connected to the compression chamber 27, and as the rotary shaft 10 rotates, the roller 21 rotates in an eccentric state with respect to the rotation center “A” in the compression chamber 27, so that the refrigerant passes through the suction pipe 6. Is sucked into the compression chamber 27. The refrigerant sucked into the compression chamber 27 is compressed by the eccentric rotation of the roller 21, and the compressed refrigerant is discharged into the sealed case 8.

  The other compression mechanism 12 includes a cylinder 25, a sub-bearing 19 and a partition plate 26 that are disposed at positions where both bodies of the cylinder 25 along the direction of the rotation center of the rotary shaft 10 are closed, A roller 23 that rotates eccentrically in the compression chamber 28 surrounded by the bearing 19 and the partition plate 26 is provided. The suction pipe 6 is connected to the compression chamber 28, and as the rotary shaft 10 rotates, the roller 23 rotates in an eccentric state with respect to the rotation center “A” in the compression chamber 28, so that the refrigerant passes through the suction pipe 6. And is sucked into the compression chamber 28. The refrigerant sucked into the compression chamber 28 is compressed by the eccentric rotation of the roller 23, and the compressed refrigerant is discharged into the sealed case 8.

  In this way, the refrigerant compressed in the compression chambers 27 and 28 is discharged into the sealed case 8 so that the sealed case 8 is filled with the compressed refrigerant. The refrigerant filled in the sealed case 8 is supplied to the condenser 2 via the discharge pipe 7.

  A process for fitting the ball bearings 20 and 22 and the rollers 21 and 23 to the eccentric portions 14 and 15 will be described with reference to FIG. The axial height dimension “Hr” of the rollers 21, 23, the axial height dimension “Hb” of the ball bearings 20, 22, and the length dimension (dimension in the rotation center direction) of the connecting portion 10 c “ The relationship with Lk ″ is set so that Hr> Lk> Hb.

  FIG. 3A shows a state in which a roller 21 with a ball bearing 20 attached to the inner peripheral portion is inserted from the side of the countershaft portion 10 b and the ball bearing 20 and the roller 21 are fitted to the outer periphery of the eccentric portion 15. .

  FIG. 3B shows a state where the ball bearing 20 is passed through the outer peripheral portion of the eccentric portion 15 and the roller 21 and the ball bearing 20 are moved to a position where the end surface of the roller 21 contacts the end surface of the eccentric portion 14. . Since the length dimension “Lk” of the connecting portion 10c and the height dimension “Hb” of the ball bearing 20 are Lk> Hb, the ball bearing 20 can be positioned on the outer peripheral portion of the connecting portion 10c. In this state, the roller 21 can be moved together with the ball bearing 20 in a direction orthogonal to the rotation center “A”. Moreover, this movement is possible even if the length dimension “Lk” of the connecting portion 10 c is smaller than the height dimension “Hr” of the roller 21.

  In FIG. 3C, the roller 21 and the ball bearing 20 are moved in the left direction orthogonal to the rotation center “A”, and the end surface of the roller 21 is positioned at a position where it does not contact the end surface of the eccentric portion 14. State.

  3D, the roller 21 and the ball bearing 20 are moved to the eccentric portion 14 side along the direction of the rotation center “A”, and the end surface of the ball bearing 20 is located at a position where it abuts against the end surface of the eccentric portion 14. FIG. It is the state made to do.

  FIG. 3E shows that the roller 21 and the ball bearing 20 are moved in the left direction orthogonal to the rotation center “A”, and the ball bearing 20 is positioned at a position where the ball bearing 20 can be fitted to the eccentric portion 14. It is in a state.

  3 (f), the roller 21 and the ball bearing 20 are moved toward the eccentric portion 14 along the direction of the center of rotation “A”, and the ball bearing 20 and the roller 21 are fitted to the outer periphery of the eccentric portion 14. It is in the state.

  FIG. 3G shows a state where the roller 21 and the ball bearing 20 are fitted on the outer periphery of the eccentric portion 14, and then the roller 23 and the ball bearing 22 are fitted on the outer periphery of the eccentric portion 15.

  In the roller 21 and the ball bearing 20 attached to the inner peripheral portion of the roller 21, the center position “X” in the height direction (axial direction) of the roller 21 and the center in the height direction (axial direction) of the ball bearing 20. The position “Y” coincides. The same applies to the roller 23 and the ball bearing 22.

  Here, in the present embodiment, for the rollers 21 and 23 and the ball bearings 20 and 22 fitted to the two eccentric portions 14 and 15, the height dimension “Hr” of the rollers 21 and 23 and the ball bearing 20 , 22 and the length dimension “Lk” of the connecting portion 10c have been described as being Hr> Lk> Hb, the relationship of Hr> Lk> Hb is The roller 21 and the ball bearing 20 that are fitted to the eccentric portion 14 on the side 10a may be filled, and the roller 23 and the ball bearing 22 that are fitted to the eccentric portion 15 on the countershaft side 10b are not necessarily filled. Absent. This is because the roller 23 and the ball bearing 22 fitted to the eccentric portion 15 do not need to pass through the connecting portion 10c. However, in order to reduce costs by sharing parts, it is preferable that the rollers 21 and 23 and the ball bearings 20 and 22 have the same shape and have a relationship of Hr> Lk> Hb.

  As shown in FIG. 2, an oil hole 29 is formed in the rotation shaft 10 along the rotation center “A” direction of the rotation shaft 10. Further, the rotary shaft 10 is formed with an oil supply hole 30 having one end communicating with the oil hole 29 and the other end communicating with the outer peripheral surfaces of the eccentric portions 14 and 15. An oil supply groove 31 extending between both end surfaces of the eccentric parts 14 and 15 is formed in a portion communicating with the oil supply hole 30 on the outer peripheral surface of the eccentric parts 14 and 15. A pump (not shown) that sucks the lubricating oil 13 stored on the bottom side in the hermetic case 8 and supplies it to the oil hole 29 is attached to the distal end side of the auxiliary shaft portion 10 b of the rotating shaft 10.

  In such a configuration, in the two-cylinder rotary compressor 1, the axial height of the rollers 21 and 23 is “Hr”, and the axial height of the ball bearings 20 and 22 is “Hb”. When the length of the connecting portion 10c is “Lk”, the roller 21 and the ball bearing 20 fitted to the eccentric portion 14 on the main shaft portion 10a side are provided by providing the relationship of Hr> Lk> Hb. Thus, the roller 21 having the ball bearing 20 mounted on the inner peripheral portion is fitted to the eccentric portion 14 even when the size of “Hr” is increased and the size of “Lk” is decreased. Can be combined.

  For this reason, since the dimension of “Lk” can be reduced, the amount of bending of the connecting portion 10 c when the rotary shaft 10 is rotated can be reduced. By reducing the amount of bending of the connecting portion 10c, it is possible to reduce the occurrence of vibration during rotation, and between the outer peripheral surfaces of the rollers 21, 23 and the inner peripheral surfaces of the cylinders 24, 25 in the compression mechanism portions 11, 12. The contact state can be stabilized. Thereby, a refrigerant | coolant can be compressed favorably and the performance as a compressor and reliability can be improved. Furthermore, since the dimension of “Lk” can be reduced, the two-cylinder rotary compressor 1 can be reduced in size.

  Further, since the dimension of “Hr” can be increased, the volume of the compression chambers 27 and 28 in the compression mechanism portions 11 and 12 can be increased, and the work amount per unit time as the compressor can be increased. it can.

  Regarding the action of the load on the roller 21 and the ball bearing 20, a radial load acts on the ball bearing 20 at one point in the center position in the height direction. On the other hand, since the pressure acts uniformly on the roller 21 in the entire height direction, it can be considered that the radial load acts on the center of the roller 21 in the height direction. Therefore, if the center position in the height direction of the ball bearing 20 and the center position in the height direction of the roller 21 do not coincide with each other, a moment acts on the roller 21, and the outer peripheral surface of the roller 21 is the inner peripheral surface of the cylinder 24. In some cases, wear or galling occurs due to contact with each other.

  In the present embodiment, since the center position “X” in the height direction of the roller 21 and the center position “Y” in the height direction of the ball bearing 20 coincide with each other, the roller 21 acts on the ball bearing 20. The point of action of the load coincides with the point at which the roller 21 is supported by the ball bearing 20. Therefore, no moment is applied to the roller 21 when the rotary shaft 10 rotates, and the occurrence of wear and galling caused by the outer peripheral surface of the roller 21 hitting the inner peripheral surface of the cylinder 24 is prevented. can do. The same applies to the roller 23 and the ball bearing 22.

  The lubricating oil 13 stored on the bottom side in the sealed case 8 is sucked up by the pump and supplied to the oil hole 29. The lubricating oil 13 supplied to the oil holes 29 is supplied to the outer peripheral surfaces of the eccentric parts 14 and 15 through the oil supply holes 30, and is further supplied to both end sides of the eccentric parts 14 and 15 through the oil supply groove 31. . Thereby, the ball bearings 20 and 22 positioned on the inner peripheral side of the rollers 21 and 23 are always maintained in a state filled with the lubricating oil 13, and the sealing performance in the thrust direction on the inner peripheral side of the rollers 21 and 23 is ensured. be able to. Therefore, the compression performance of the refrigerant in the compression mechanisms 11 and 12 can be maintained in a good state.

  The diameter dimension “φDs” of the sub-shaft portion 10b is set smaller than the diameter dimension “φDm” of the main shaft portion 10a.

  Even when the diameter dimension “φDs” of the sub-shaft portion 10 b is smaller than the diameter dimension “φDm” of the main shaft portion 10 a, the ball bearing 18 that pivotally supports the sub-shaft portion 10 b has a larger load resistance than the ball bearing 16. By using one having a diameter, it is possible to prevent shaft wear or the like of the auxiliary shaft portion 10b. Further, by making the diameter dimension “φDs” of the sub-shaft portion 10b smaller than the diameter dimension “φDm” of the main shaft portion 10a, the eccentric amount of the eccentric portions 14 and 15 can be increased, the displacement volume can be increased, and the refrigeration cycle apparatus The refrigeration capacity can be increased. That is, when the eccentric amount of the eccentric portions 14 and 15 is increased in order to increase the displacement volume of the compression chambers 27 and 28, the outer peripheral surfaces of the eccentric portions 14 and 15 in the anti-eccentric direction are the main shaft portion 10a and the auxiliary shaft. The rollers 21 and 23 cannot be inserted into the eccentric portions 14 and 15 by biting inside the outer peripheral surface of the portion 10b, but the diameter dimension “φDs” of the auxiliary shaft portion 10b into which the rollers 21 and 23 are inserted is the diameter size of the main shaft portion 10a. By making it smaller than “φDm”, the eccentric amount can be increased without the outer peripheral surface of the eccentric portions 14 and 15 in the anti-eccentric direction biting into the inner peripheral surface of the auxiliary shaft portion 10b.

  The present invention can be applied not only to the vertical two-cylinder rotary compressor shown in the above embodiment, but also to a horizontal two-cylinder rotary compressor.

It is the schematic which shows the refrigerating-cycle apparatus provided with the 2 cylinder type rotary compressor of one embodiment of this invention. It is a front view which shows a part of 2 cylinder type | mold rotary compressor in a cross section. It is process drawing explaining the process in the case of fitting a ball bearing and a roller with respect to an eccentric part. It is sectional drawing which shows the rotating shaft which has two eccentric parts in the 2 cylinder type rotary compressor of a prior art example, and the roller fitted to the eccentric part. It is process drawing explaining the process in the case of fitting a roller with respect to the eccentric part in a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 2 cylinder type rotary compressor 2 Condenser 3 Expansion apparatus 4 Evaporator 8 Sealed case 9 Electric motor part 10 Rotating shaft 10c Connection part 11,12 Compression mechanism part 14,15 Eccentric part 20,22 Ball bearing 21,23 Roller 29 Oil hole 30 Oil supply hole 31 Oil supply groove

Claims (4)

Driven by rotating the rotation shaft about the rotation center, the rotation shaft having two eccentric portions formed at positions shifted by 180 degrees with respect to the rotation center and coupled to the motor portion, and the rotation shaft A two-cylinder rotary compressor in which the two compression mechanisms are housed in a sealed case,
The compression mechanism has a roller attached to the eccentric part via a ball bearing,
When the axial height dimension of the roller is Hr, the axial height dimension of the ball bearing is Hb, and the length dimension of the connecting portion connecting the two eccentric portions of the rotating shaft is Lk. ,
Hr>Lk> Hb
A two-cylinder rotary compressor characterized by having a relationship of   2. The two-cylinder rotary compressor according to claim 1, wherein axial centers of the roller and the ball bearing are matched.   An oil hole formed in the rotation shaft along the direction of the rotation center of the rotation shaft, an oil supply hole communicating the outer peripheral surface of the eccentric portion and the oil hole, and the eccentricity on the outer peripheral surface of the eccentric portion The two-cylinder rotary compressor according to claim 1, further comprising an oil supply groove that communicates with the oil supply hole formed between both end faces of the portion. A two-cylinder rotary compressor according to any one of claims 1 to 3,
A condenser connected to the two-cylinder rotary compressor;
An expansion device connected to the condenser;
An evaporator connected to the expansion device;
A refrigeration cycle apparatus comprising:

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