KR20080069123A - A rotary compressor and a refrigerating cycle machine with the same - Google Patents

Abstract

A rotary compressor and a refrigeration cycle having the same are provided to reduce operational noise and to shorten a height of a rotor by extending a length of a main bearing and installing a counter bore. A rotary compressor comprises a sealed case(2), an electric motor unit(3), and a compressing machine unit(5). The electric motor, contained in the sealed case, has a stator(31) and a rotor(32) rotated in the stator. A bearing member supporting the rotary shaft is installed at the compressing machine unit side of the electric motor unit. The compressing machine unit, assembled to the electric motor through a rotary shaft(4), includes a cylinder(51) having a cylinder chamber, a roller(55), and a main bearing(52). The roller is fitted to an eccentric part of the rotary shaft and eccentrically rotated in the cylinder chamber of the cylinder. The main bearing supports a main shaft unit of the rotary shaft. The distance between two ends of the main bearing and a center shaft of an entire rotary member composed of the rotor, the rotary shaft, and the roller is over a main shaft unit's bore size.

Description

Refrigeration cycle unit with rotary compressor and rotary compressor {A ROTARY COMPRESSOR AND A REFRIGERATING CYCLE MACHINE WITH THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary compressor and a refrigeration cycle apparatus including the rotary compressor. More particularly, the present invention relates to a rotary compressor provided with a bearing member supporting a rotating shaft only on the compression mechanism side of an electric motor, and a refrigeration cycle apparatus including the rotary compressor. .

Conventional rotary compressors generally have a problem that vibration is liable to occur because a bearing member supporting a rotating shaft is a piece supporting structure provided only at the compression mechanism side of the electric motor.

Therefore, the rotary compressor which provided the bearing member also in the semi-compression mechanism part side of an electric motor part, and made both support structures is proposed by Unexamined-Japanese-Patent No. 2001-323886.

However, both support structures described in Japanese Unexamined Patent Application Publication No. 2001-323886 have a problem in that the number of parts increases and the care of both bearing members needs to be performed precisely, resulting in an increase in cost.

In addition, in a rotary compressor having a single support structure, a flywheel is installed on the rotor of the motor unit to bring the center of the rotor closer to the bearing side, and a hermetic rotary compressor for reducing the swing width of the rotor is disclosed in Japanese Laid-Open Patent Publication 2002. Proposed in -130171.

However, the rotary compressor described in Japanese Laid-Open Patent Publication No. 2002-130171 is not considered with respect to the position of the center of the entire rotating body composed of the rotor, the rotating shaft, and the rollers, so that the vibration cannot be sufficiently reduced.

The present invention has been made in consideration of the above-described circumstances, and an object thereof is to provide a rotary compressor having excellent shock resistance.

It is another object of the present invention to provide a refrigeration cycle apparatus having a rotary compressor and excellent in shock resistance.

In order to achieve the above object, the rotary compressor according to the present invention comprises a sealed case, an electric motor unit accommodated in the sealed case, and a compression mechanism unit connected to the electric motor unit through a rotating shaft, and supports the rotating shaft. The bearing member is provided only on the compressor sphere side of the motor unit, and the motor unit includes a stator and a rotor rotatably disposed on an inner circumference of the stator, and the compressor sphere includes a cylinder having a cylinder chamber; And a roller for eccentrically rotating the cylinder chamber in accordance with an eccentric portion of the rotary shaft, and a main bearing for supporting a main shaft portion of the rotary shaft, wherein the rotor, the rotary shaft, and the roller are all rotary bodies. The axial position of the center of the axis of the main shaft portion of the rotary shaft from both ends of the main bearing It is characterized in that it is in the range which becomes inner more than the distance corresponded to a diameter. It is characterized by the above-mentioned.

In addition, the refrigeration cycle apparatus according to the present invention is characterized by consisting of a rotary compressor, a condenser, an expansion device, and an evaporator having the above configuration.

According to the rotary compressor which concerns on this invention, the rotary compressor excellent in earthquake resistance can be provided.

Moreover, the refrigeration cycle apparatus which concerns on this invention can provide the refrigeration cycle apparatus provided with a rotary compressor, and excellent in earthquake resistance.

A rotary compressor and a refrigeration cycle apparatus including the rotary compressor according to an embodiment of the present invention will be described with reference to the drawings.

1 is a conceptual diagram of a rotary compressor and a refrigeration cycle apparatus including the rotary compressor according to an embodiment of the present invention.

As shown in Fig. 1, in the refrigeration cycle apparatus 21 according to the present invention, the rotary compressor 1, the condenser 22, the expansion device 23, and the evaporator 24 of the present embodiment are piped in an annular shape. .

The rotary compressor 1 includes a sealed container 2, and is composed of an electric motor part 3 accommodated in the sealed container 2 and a compression mechanism part 5 connected to the electric motor part 3 via a rotating shaft.

The motor part 3 is a stator 31 press-fitted into the hermetic container 2 and a rotor 32 rotatably disposed on an inner circumference of the stator 31 and fixedly attached to an upper end of the rotating shaft 4. The rotor 32 is provided with a hollow counterbore 32a having a depth of up to half or more of the height of the rotor 32.

The compression mechanism part 5 is provided below the electric motor part 3, and has the cylinder 51 located in the lower part of the rotating shaft 4. As shown in FIG. A main bearing 52 is attached to and fixed to an upper surface of the cylinder 51, and a sub bearing 53 is attached to and fixed to a lower surface of the cylinder 51, and surrounded by the cylinder 51, the main bearing 52, and the sub bearing 53. The cylinder chamber 54 is formed in a space part.

The main bearing 52 and the sub-bearing 53 are set in the relationship that H1> 3 * H2, when the total height is set to H1 and H2.

The cylinder chamber 54 is provided with an eccentric portion 4a which is integrally provided with the rotation shaft 4 and a roller 55 engaged with the main surface of the eccentric portion 4a.

The rollers 55 are all equal in thickness along the circumferential direction thereof, and eccentrically rotates together with the eccentric portion 4a with the rotation of the rotary shaft 4. A part of the outer circumferential wall along the axial direction of the roller 55 is made to be almost in contact with the inner circumferential wall of the cylinder 51, and with the eccentric rotation of the roller 55, the contact position thereof is along the circumferential direction of the cylinder 51. Is gradually displaced.

The blade 56 is in contact with the outer circumferential wall of the roller 55 along the axial direction.

One end of the blade 56 is elastically oppressed by the spring member 58 accommodated in the spring receiving hole 57, so that the other end of the blade 56 elastically contacts the main surface of the roller 55. It is becoming.

The blade 56 protrudes into the cylinder chamber 54, and one end of the blade 56 opens in the cylinder chamber 54, and the other end slides in the blade slot 59, which opens in the rear hole (not shown). The cylinder chamber 54 is partitioned between the compression chamber side communicating with the discharge part 52h provided in the main bearing 52 and the suction chamber side communicating with the suction hole (not shown).

In addition, the main bearing 52 is covered with a main bearing cover 60 that includes a vent hole (not shown) and makes a noise function. The discharge part 52h communicates with the condenser 22 and the suction hole communicates with the evaporator 24, respectively.

As described above, the rotor 32 is fixedly attached to the upper end portion, and the rotating shaft 4 on which the roller 55 is engaged with the eccentric portion 4a provided near the lower end portion is supported by the knitting support structure.

For example, the upper shaft end 4b of the rotating shaft 4 is in a free state not supported by any member, and is provided with a bearing member provided only on the compression mechanism part 5 side, for example, a constituent member of the compression mechanism part 5. It is supported by the main bearing 52 and the sub bearing 53 which form a part.

The main bearing 52 consists of a substantially disk-shaped bearing base 52a and a bearing portion 52b that stands up from the bearing base 52a and supports the main shaft portion 4c of the rotating shaft 4 therethrough.

The main bearing 52, i.e., the bearing portion 52b, is fluidly fitted to the counterbore 32a, and the upper end 52c of the bearing portion 52b reaches at least half the height of the rotor 32, The lower end 52d reaches the lower surface 52e of the bearing base 52a.

In this bearing structure, the axial position Zg of the center of the whole rotating body 61 composed of the rotor 32, the rotating shaft 4 and the roller 55 is the upper end 52c of the main bearing 52, It sets so that it may exist in the range Z (Z = H1-2 * D) which becomes inward more than the distance corresponding to diameter D of the main shaft part 4c of the rotating shaft 4, respectively from the lower end 52d. The radial position (horizontal) of the center is preferably on the axis of the rotational axis, but is not necessarily limited to the axis of the core as long as the balance during rotation of the entire rotating body is maintained.

Moreover, the roll off 62 is provided in at least one of the inner peripheral surface of the range Z of the main bearing 52, and the outer peripheral surface of the main shaft part 4c which opposes. In addition, the sub bearing 53 supports the sub shaft portion 4d of the rotation shaft 4.

The rotary compressor (1) having the above structure is (1). In general, the main bearing (52) of the rotary compressor (1) which is stable and rotates is fluid lubrication or boundary lubrication. Here, the fluid lubrication means that the rotary shaft 4 is supported only by the pressure of the oil film existing in the gap between the main bearing 52 and the rotary shaft 4, and the boundary lubrication means that the solid contact portion is generated. The oil film pressure distribution inside the main bearing 52 is not the same in the axial longitudinal direction, but is concentrated near both ends of the main bearing 52.

(2) In view of reliability and mechanical efficiency, an optimum value exists in the bearing height (length) H0 / axis diameter D, and is set to be generally 0.6 to 1.0.

In the above (1), the main bearing 52 is divided into two upper bearing portions 52f and a lower bearing portion 52g near the upper end of the bearing and near the lower end. In said (2), it is thought that the bearing surface which has the width | variety of the axial diameter D has sufficient load capacity.

In consideration of these, the rotary compressor 1 has a structure in which the center of the rotation system is sandwiched between the upper bearing portion 52f and the lower bearing portion 52g having two sufficient load capacities.

Therefore, by having the above structure, the rotary compressor can support the inertial force generated by the vibration or the like substantially on both sides of the support structure, and can be almost evenly supported on the bearing surfaces on both ends of the main bearing 52. And a rotary compressor excellent in vibration resistance.

In the bearing structure, in order to realize that the main bearing 52 is divided into two upper bearing portions 52f and lower bearing portions 52g near the upper end and the lower end of the bearing, it is easiest to lengthen the main bearing. Since the sliding frictional loss also occurs on the bearing surface that hardly supports the axial load, it is not preferable to lengthen the bearing surface because the sliding area becomes large and the sliding frictional loss increases. In addition, problems such as an increase in oil supply resistance also occur.

In order to solve these problems, it is preferable to form the roll-off 62 in at least one of the bearing inner peripheral surface of the range Z of the main bearing 52, and the outer peripheral surface of the main shaft part 4c of the rotating shaft 4 which opposes as mentioned above. Do.

As a result, in the roll-off 62, the clearance between the shaft surface and the bearing surface is large, the oil film shear rate uniformity of the portion is small, and the sliding friction loss is reduced, so that the main bearing 52 (bearing portion 52b) is made long. The area of the sliding surface can be reduced, and the increase in sliding friction loss can be significantly suppressed. In addition, the width of the sliding portion is appropriate, thereby improving the reliability and mechanical efficiency.

In the rotary compressor 1 having the above structure, the rotor 32 is provided with the counterbore 32a more than half of its entire length. Usually, since the rotor 32 occupies most of the mass of the rotor, it is preferable to install the counterbore 32a with the extension of the length of the main bearing 52 to reduce the substantial height of the rotor 32. . Thereby, the distance which corresponds to the diameter D of the main shaft part 4c in the axial position of the center of the whole rotating body 61 within the range of the main bearing 52, and from both ends of the main bearing 52. It becomes easy to set in the range which becomes above an inside. Moreover, the drawback of lengthening the main bearing 52, such as the enlargement of the rotary compressor 1 and the increase in the center, the unnecessary space generated in the electric motor part 3, can be eliminated.

In the rotary compressor 1 having the above-described structure, H1> 3 * H2 is set. This suppresses the occurrence of the noise of the frequency near "the number of magnetic poles of the rotor x driving frequency" (the noise of 4 x f (operation frequency) when employing the four-pole magnetic pole) and operates the rotary compressor. Can reduce the noise.

The reason for the noise reduction is as follows.

In the conventional rotary compressor having a single bearing structure supporting the rotating shaft with a main bearing of insufficient height, the bearing part and the sub bearing of the lower side of the main bearing support the compression load almost evenly, and the upper side of the main bearing closest to the rotor. It is a structure which supports the rocking load of a rotation drive part in a bearing part, and generally sets it as the total height H1 of a main bearing and the total height H2 of a sub bearing, and the relationship of the following formula is established.

In structure, the larger α is, the more favorable the rotation imbalance of the rotation drive unit is (axial load, swing amount). When supporting the load which overflowed for the said reason, it is preferable to support by two or more support points which were as far apart as possible. From the moment equation, it can be seen that the longer the distance between the support points and the shorter the distance between the load points and the support points, the smaller the force generated at the support points.

As a result of the recent pursuit of energy saving properties, the problem of the noise of the frequency near the "stimulator number of the rotor x driving frequency" of the rotor is increasing year by year. That is, specific measures for energy saving pursuit include, for example, an increase in the electromagnetic force due to the increase in the number of turns, the adoption of rare earth magnets, the countershaft thinning, and the eccentric thinning.

The noise and the swing of the rotor are closely related, and the reduction of the swing of the rotor has become an important problem.

The generating mechanism of the noise is considered as follows.

The distance between the magnet of the rotor and the teeth of the stator is uneven.The radial component of the force acting on each magnet is not canceled.The radial excitation force is generated on the rotor and the stator separately. Deformation of stator ⇒ case surface vibrates ⇒ noise of frequency around "stimulator number X driving frequency of rotor".

In addition to the assembly precision and the part precision, the rotation of the rotor is also large as a cause of the non-uniform distance between the magnet and the tooth, and the rotation of the rotor is related to the attitude of the bearing in the bearing, the rigidity of the shaft, and the force acting on the rotor. Force (location and size of working point).

Therefore, the rotational suppression of the rotor is effective as the noise countermeasure and is realized by setting H1> 3 * H2.

According to the rotary compressor according to the present embodiment, it is possible to provide a rotary compressor having excellent seismic resistance.

Moreover, the refrigeration cycle apparatus which concerns on this invention can provide the refrigeration cycle apparatus provided with a rotary compressor and excellent in earthquake resistance.

1 is a conceptual diagram of a refrigeration cycle apparatus having a rotary compressor and a rotary compressor according to an embodiment of the present invention.

* Explanation of symbols for the main parts of the drawings

1: rotary compressor 2: airtight container

3: motor part 4: rotating shaft

4a: eccentric 4c: main shaft

5: compression mechanism part 21: refrigeration cycle device

22 condenser 23 expansion device

24: evaporator 31: stator

32: rotor 32a: counterbore

51: cylinder 52: main bearing

52b: bearing part 52d: lower end

52e: Lower surface 52f: Upper bearing portion

52 g: lower bearing 53: sub-bearing

54: cylinder chamber 55: roller

56: blade 61: the entire rotating body

62: roll off

Claims (5)

Sealed case, An electric motor unit accommodated in the sealed case, and Compressor section is connected to the electric motor through a rotating shaft, The bearing member which supports the said rotating shaft is provided only in the said compression mechanism part side of the said motor part, The motor unit includes a stator and a rotor rotatably disposed on an inner circumference of the stator. In the rotary compressor comprising a cylinder having a cylinder chamber, a roller which is engaged with the eccentric portion of the rotary shaft, the roller eccentrically rotates in the cylinder chamber, and a main bearing supporting the main shaft portion of the rotary shaft. A rotary compressor characterized in that the axial position of the center of the entire rotating body consisting of the rotor, the rotating shaft and the roller is in the range from the both ends of the main bearing to the inside more than a distance corresponding to the diameter of the main shaft of the rotating shaft. . The method of claim 1, And a roll-off is provided on at least one of an inner circumferential surface of the bearing separated from a distance corresponding to a diameter of the main shaft portion from both ends of the main bearing and an outer circumferential surface of the main shaft portion of the rotating shaft opposite to the inner circumferential surface of the bearing. The method according to claim 1 or 2, And said rotor is provided with a counterbore having a length of at least half of its total length. A refrigeration cycle device comprising the rotary compressor, condenser, expansion device, and evaporator of claim 1. A refrigeration cycle device comprising the rotary compressor, condenser, expansion device, and evaporator of claim 3.

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