JPH08247059A - Rotary compressor - Google Patents

Abstract

PURPOSE: To improve reliability of a shaft part by reducing a PV value applied on an eccentric part without spoiling compression efficiency even in the case of flattening a cylinder for highly increase in efficiency, the case of using a refrigerant having high differential pressure, or the like. CONSTITUTION: Height of a sliding part S between a roller 5 and an eccentric part 41 is made as much as or more than height of a cylinder 1 in a rotary compressor furnished with the cylinder 1 partitioning a cylinder chamber 11, a front head 2 arranged on an end part of this cylinder 1 and a rear head 3 and provided with the roller 5 to fit on the eccentric part 41 of a driving shaft 4 built in the cylinder chamber 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary compressor mainly used for refrigeration equipment.

[0002]

2. Description of the Related Art Generally, as a rotary compressor, as shown in FIG. 8, a hermetic casing A is internally provided with a motor B and a compression element CF including a cylinder C, a front head D and a rear head E, and the cylinder C is provided in the cylinder C. It is known that a roller PS that forms a cylinder chamber C1 and that is housed inside the cylinder chamber C1 compresses the refrigerant gas as the eccentric portion K1 of the drive shaft K connected to the motor B rotates eccentrically.

By the way, in recent years, rotary compressors have been required to be miniaturized while maintaining high compression efficiency and keeping the cylinder volume unchanged. In particular, recently, a high-pressure refrigerant has been used for the replacement of CFC. (For example, R407B,
R407C, R410A, etc.) is used, but since such a refrigerant has a large gas differential pressure during use, a reduction in compression efficiency due to leakage of refrigerant gas from the high pressure side to the low pressure side of the cylinder chamber becomes a problem, Improvement of compression efficiency is required.

Therefore, in the prior art, for example, Japanese Patent Laid-Open No. 6-5.
As disclosed in Japanese Patent No. 8277 and as shown in FIG. 9, a configuration is adopted in which the thickness of the cylinder J can be made thin, so that the cylinder J can be flattened to meet the demand for downsizing and the roller I By reducing the wall thickness, the contact ratio of the contact points where the roller J and the blade (not shown) that slides in the cylinder chamber J1 come into contact with each other is reduced to reduce the leakage amount of the compressed gas and improve the compression efficiency. I am trying.

[0005]

In the rotary compressor, the load on the shafts K and K1 is generally the load due to the compressed gas, and the load (F) due to the compressed gas is , Roller bearing projected area (Λ) (Λ =
It depends on the roller diameter d × height h).
In the conventional rotary compressor as shown in Fig. 1, since the cylinder J is flattened for high efficiency, the thickness of the roller I becomes thin accordingly, and the roller I is compressed by the compressed gas. Although the load (F) does not change, the bearing projected area (Λ) of the roller decreases due to the thinning of the roller I,
Therefore, the load per unit (P value) (P = F / Λ) applied to the eccentric portion G1 thinned according to the roller I becomes large.

On the other hand, when a refrigerant having a high gas differential pressure is used, even when the flattening of the cylinder is not achieved as described above, that is, when the bearing projected area (Λ) does not change, The load (F) applied to the roller is larger than that of the conventional rotary compressor that uses Freon as the refrigerant gas, and the P value applied to the eccentric portion G1 is accordingly increased.

As described above, the P value applied to the eccentric portion G1 becomes large when the cylinder is flattened for high efficiency or when a refrigerant having a high gas differential pressure is used. The PV value of the eccentric portion G (P is the surface pressure, V is the moving speed) increases, and the reliability of the eccentric portion G1 is impaired.

That is, the PV value is P · V = F /
It can be represented by (d · h) · 2πdn (n is the number of revolutions), and in order to reduce the PV value without impairing the compression efficiency, the bearing projected area (Λ = d · h) may be increased. However, even if the diameter d of the roller is increased, the projected area of the bearing (Λ) is increased, but the sliding speed (V = 2πdn) is also increased, so that the PV value cannot be decreased, and the roller value is also decreased. As described above, the height h of the cylinder is also in the direction of flattening the cylinder for higher efficiency, and is restricted by the height of the cylinder. Therefore, in the case of the conventional configuration, the compression efficiency is impaired. PV of eccentric part without
It was difficult to lower the value.

The present invention has been made in view of the above problems, and when the cylinder is flattened for higher efficiency or when a refrigerant having a high gas differential pressure is used, compression is performed. P on the eccentric part without sacrificing efficiency
An object of the present invention is to provide a rotary compressor that reduces the V value and improves the reliability of the shaft portion.

[0010]

To achieve the above object, in the invention according to claim 1, a cylinder 1 defining a cylinder chamber 11, and a front head 2 and a rear head arranged at an end of the cylinder 1 are provided. In the rotary compressor including the roller chamber 5 and the roller chamber 5 fitted in the eccentric portion 41 of the drive shaft 4 in the cylinder chamber 11, the roller 5 and the eccentric portion 41
The height of the sliding portion S between and is greater than or equal to the height of the cylinder 1.

In the second aspect of the invention, the height of each of the roller 5 and the insertion portion of the eccentric portion 41 is equal to or higher than the height of the cylinder 1.

According to the third aspect of the present invention, a cylindrical fixed bush 8 higher than the height of the cylinder chamber 11 is fixed to the inner circumference of the roller 5, and the fixed bush 8 is slidably and slidably received. The height of the outer peripheral surface of the eccentric portion 41 is equal to or higher than the height of the cylinder 1.

According to a fourth aspect of the present invention, a tubular floating bush 9 higher than the cylinder 1 is slidably and slidably fitted on the inner periphery of the roller 5, and the floating bush 9 is slid and slid. The height of the outer peripheral surface of the eccentric portion 41 that is freely received is equal to or higher than the height of the cylinder 1.

[0014]

According to the first aspect of the invention, the height of the sliding portion S between the eccentric portion 41 of the drive shaft 4 and the roller 5 is equal to or higher than the height of the cylinder 1. Since the height of the sliding surface of the roller 5 is increased while keeping the height as it is, the projected area (Λ) of the bearing can be increased without impairing the compression efficiency, and the load per unit ( It is possible to reduce the P value), reduce the PV value applied to the eccentric portion 41, and improve the reliability of the shaft portions 4 and 41.

According to the second aspect of the present invention, the respective heights of the roller 5 and the eccentric portion 41 at the insertion portion are
The height of the sliding portion S can be made equal to or higher than the height of the cylinder 1 only by making a simple design change so that the height is equal to or higher than the height of the cylinder 1.

According to the third aspect of the present invention, the eccentric portion 41 is set to a height of the cylinder 1 or more, and the fixed bush 8 having a height of the cylinder 1 or more is provided on the inner peripheral side of the roller 5. By inserting and fixing, the contact area between the roller 5 and the eccentric portion 41 is increased through the fixing bush 8 to reduce the PV value. Therefore, the roller 5 is separately processed. The initial purpose can be achieved with a simple structure using the fixed bush 8 without performing the above.

According to the fourth aspect of the present invention, the eccentric portion 41 is set to be higher than the height of the cylinder 1, and the floating distance between the eccentric portion 41 and the roller 5 is equal to or higher than the height of the cylinder 1. Since the bush 9 is slidably interposed, the roller 5 is moved to the cylinder chamber 11 as the eccentric portion 41 rotates.
When driven to rotate inside, the eccentric portion 41 and the roller 5 are
And the floating bush 9 is relatively rotating with respect to the roller 5 and the eccentric portion 41 while sliding.
Since the roller 5 and the eccentric portion 41 follow and rotate at an intermediate speed v lower than that of the roller 5, the floating bush 9 has a lower V value than the roller 5, and the eccentric portion 41 has the floating bush. 9 and the height of the eccentric portion 41 are the same as those of the cylinder 1
Since the contact area between them is increased, that is, the projected area of the bearing is increased and the P value is decreased, the height between the floating bush 9 and the eccentric portion 41 and the roller 5 is increased. Therefore, the PV value applied to the eccentric part can be reduced with a simple structure in which the floating bush 9 is added without separately processing the roller 5. The reliability of the parts 4 and 41 can be improved.

[0018]

1 to 7 show a swing type rotary compressor. This compressor has a flat cylinder 1 for achieving high efficiency and upper and lower parts of the cylinder 1. Front and rear heads 2 and 3 facing each other, a cylinder chamber 11 is formed inside the cylinder 1 surrounded by the heads 2 and 3, and a drive shaft 4 extending from the motor side is formed in the cylinder chamber 11. By disposing the cylindrical roller 5 which is fitted in the eccentric portion 41 so as to be relatively rotatable,
A blade 51 extending radially outward on the outer peripheral portion of the roller 5.
And the cylinder chamber 11 is provided between the suction port 12 and the discharge port 13 provided in the cylinder 1.
Is formed in the holding hole 14, and the swinging guide bush 6 composed of split bushes 6A and 6B divided into two is arranged in the holding hole 14, and the receiving secured between the bushes 6A and 6B. By inserting the protruding tip side of the blade 51 freely into the groove 61, the low pressure chamber Y communicating with the suction port 12 and the high pressure chamber X communicating with the discharge port 13 by the blade 51. Is defined in.

With the rotation of the drive shaft 4, the roller 5 is driven to revolve in the cylinder chamber 11 without rotating on its axis, that is, relative rotation accompanied by slippage between the roller 5 and the eccentric portion 41 is performed. By performing revolving drive while being performed, the refrigerant gas sucked from the suction port 13 into the low pressure chamber Y is compressed and discharged from the high pressure chamber X through the discharge port 13 to the outside. In FIG. 7, a discharge port 13 that opens to the high pressure chamber X side of the cylinder chamber 11 is provided on the outer peripheral portion of the cylinder 1, and the discharge port 1
3 has a side discharge structure that discharges the refrigerant gas compressed in the high-pressure chamber X from the discharge port 13 into the closed casing. Further, in the figure, 7 is a discharge valve provided at the discharge port 13, and 71 is a valve retainer thereof.

With the above-mentioned structure, however, in the first embodiment shown in FIG. 1, at the upper and lower ends of the inner peripheral edge of the roller 5,
The annular extending portions 52 protruding in the vertical direction are integrally formed to form a sliding surface having a height equal to or higher than the height H2 of the cylinder 1 and the outer peripheral surface 4 of the eccentric portion 41.
The axial height of 2 is formed to be substantially the same as the sliding surface of the roller, and the sliding surface of the roller 5 and the outer peripheral surface 42 of the eccentric portion 41 form the sliding portion S. The vertical height H1 of the slidable portion S is set to be equal to or higher than the height H2 of the cylinder 1.

The cylinders of the front head 2 and the rear head 3 are arranged so that the sliding portion S formed at a height higher than the height of the cylinder 1 can be eccentrically rotated in the cylinder chamber 11. On the surface facing the chamber 11, annular receiving portions 23, 33 for receiving the slidable portion S so as to be eccentrically rotatable by the rotation of the drive shaft are formed. In the height direction, the receiving portions 23 and 33 have at least the height H1 of the sliding portion S and a predetermined gap required for revolving driving,
Further, in the radial direction, at least the sliding portion S on the large-diameter side of the eccentric portion 41 has a predetermined width that allows eccentric rotation, and communicates with the cylinder chamber 11 defined by the cylinder 1 and the roller 5. Good if not. In the first embodiment, the receiving portions 23 and 33 are annular receiving portions 22 and 33 as shown in the AA line end views of the front head 2 of the first embodiment shown in FIGS. 1 and 2. 32 and annular recesses 21, 31 deeper than that
In this case, the management plane facing the upper and lower end surfaces of the eccentric portion 41 is limited to the end surfaces of the receiving portions 22 and 32, and the finishing processing area is reduced to reduce the processing management.

Incidentally, in FIG. 1, an annular extending portion 52 is provided.
Are formed at both ends of the upper and lower ends of the inner peripheral edge of the roller 5, the extension 52 is formed at either the upper end or the lower end of the inner peripheral edge of the roller 5, so that the sliding surface height of the roller 5 is increased. H1 may be formed to be higher than the height H2 of the cylinder 1, and in such a case, either the receiving portion 23 formed in the front head 2 or the receiving portion 33 formed in the rear head 3 becomes unnecessary.

As described above, the vertical height H of the sliding portion S
By increasing the height of the cylinder 1 to be equal to or higher than the vertical height H2 of the cylinder 1, the height of the cylinder 1 is maintained as it is, and the roller 5
Since the height of the sliding surface of the eccentric part 4 is increased, the contact area between the two is increased without impairing the compression efficiency, that is, the projected area of the bearing (Λ) is increased to increase the eccentric portion 4.
Since the PV value of the eccentric part 41 can be reduced by reducing the load per unit (P value) applied to the unit 1, the cylinder having a high gas differential pressure is used when the cylinder is flattened for high efficiency. Even in such a case, the load on the eccentric portion 41 can be reduced, and the reliability of the shaft portions 4 and 41 can be improved.

In the second embodiment shown in FIG. 3, the roller 5 is
On the inner peripheral side of the cylinder, the height H1 of the cylinder 1 is higher than the height H2
By fixing a cylindrical fixed bush 8 such as a bearing metal having a cylinder with a press-fitting means or the like, the height H2 of the cylinder 1 can be increased.
The sliding surface having the above height is formed, and the axial height of the outer peripheral surface 42 of the eccentric portion 41 is formed to be substantially the same as the sliding surface of the roller 5, The sliding surface of the roller 5 and the outer peripheral surface 42 of the eccentric portion 41 form a sliding portion S, and the vertical height H1 of the sliding portion S is made higher than the height H2 of the cylinder 1. are doing.

Then, in the surfaces of the front head 2 and the rear head 3 facing the cylinder chamber 11, the slidable portion S is eccentrically rotatably received by the rotation of the drive shaft 4, as in the first embodiment. The annular receiving portions 23, 33 are formed, and the receiving portions 23, 3 are also formed in the second embodiment.
3 is formed from the annular receiving portions 22 and 32 and the annular recesses 21 and 31 deeper than the annular receiving portions 22 and 32, and the management plane facing the upper and lower end surfaces of the eccentric portion 41 is used only as the end surfaces of the receiving portions 22 and 32 for finishing. The area is reduced and processing control can be reduced.

Further, in the embodiment shown in FIG. 3, the cylindrical fixing bush 8 is fixed to both ends of the inner peripheral side upper and lower ends of the roller 5 so as to project substantially uniformly, but as shown in FIG. In addition, it may be fixed so as to project only at the upper end, or as shown in FIG. 5, so as to project only at the lower end. In such a case, in FIG. 4, the receiving portion 33 formed in the rear head 3 is In FIG. 5, the receiving portions 23 formed on the front head 2 are not required.

According to the above configuration, the contact area of the sliding portion S, that is, the contact area between the fixed bush 8 and the eccentric portion 41 is increased, that is, the bearing projected area (Λ) is increased. The load per unit (P value) applied to the eccentric portion can be reduced to reduce the PV value applied to the eccentric portion 41. Therefore, as in the case of FIG. 1, the roller 5 is separately processed. The initial purpose can be achieved with a simple configuration using the fixed bush 8 without using the above.

In the third embodiment shown in FIG. 6, the roller 5 and the eccentric portion 4 are replaced by the fixed bush 8 of the second embodiment.
1, a cylindrical floating bush 9 having a height H1 which is equal to or higher than the height H2 of the cylinder chamber 11 is rotatably interposed, and the axial height of the outer peripheral surface 42 of the eccentric portion 41 is set to the axial height. The sliding surface of the roller 5 and the outer peripheral surface 4 of the eccentric portion 41 are formed to have substantially the same height as the sliding surface of the roller.
A slidable portion S is formed by 2 and the vertical height H1 of this slidable portion S is equal to or higher than the height H2 of the cylinder 1. Then, similarly to the first embodiment, on the surfaces of the front head 2 and the rear head 3 facing the cylinder chamber 11, the slidable portion S is eccentrically rotatably received by the rotation of the drive shaft 4. Although the portions 23 and 33 are formed, in the third embodiment, the tubular floating bush 9 forming the slidable portion S is merely rotatably interposed, and the first embodiment is different from the first embodiment. Alternatively, as in the second embodiment, the roller 5
Since it is not integrally formed with or is not fixed to the roller 5, the receiving portions 23 and 33 are not formed with annular recesses but are formed as flat surfaces.

Incidentally, in the embodiment shown in FIG. 6, the cylindrical floating bush 9 is interposed so as to project substantially evenly at both ends of the inner peripheral side upper and lower ends of the roller 5, but the second embodiment Similar to the example, it may be interposed so as to project only at the upper end or only at the lower end. In such a case, it is formed in the receiving portion 33 formed in the rear head 3 or the front head 2. One of the receiving units 23 becomes unnecessary.

According to the above construction, the height of the sliding portion S, that is, the height H1 of the floating bush 9 and the eccentric portion 41 is
The cylinder 1 is formed to have a height of H2 or more, which increases the contact area between them and the projected area of the bearing (Λ), thereby increasing the load per unit (P Value) can be reduced to reduce the PV value applied to the eccentric portion 41, and when the roller 5 is rotationally driven in the cylinder chamber 11 as the eccentric portion 41 rotates, the eccentric portion 41 and the roller 5, the floating bush 9 rotates relative to the roller 5 with slippage, and rotates following the roller 5 at an intermediate speed v lower than that of the roller 5, so that the V value is reduced. Thereby, the PV value can be reduced. Therefore, the PV value applied to the eccentric portion can be reduced and the reliability of the shaft portions 4 and 41 can be improved with a simple structure in which the floating bush 9 is interposed without separately processing the roller 5. You can

Incidentally, in the first to third embodiments,
The entire height of the eccentric portion 41 is determined by the outer peripheral surface 42
The same height H1 as that of the eccentric portion, that is, the same height H1 as the inner peripheral sliding surface of the roller 5 including the extending portion 52 or the fixed or floating bushes 8 and 9. 41 may be formed so that only a part of its outer peripheral surface has the same height H1 as the fixed and floating bushes 8, 9 and the like. In this case, the sliding surface in the vertical direction of the eccentric portion 41 is only the end surface of a part of the outer peripheral surface, and the sliding resistance at the end surface of the eccentric portion 41 facing the cylinder heads 2 and 3 is reduced. .

Further, in the first to third embodiments, annular oil grooves 53 are formed on the upper and lower surfaces of the roller 5 on the surfaces facing the heads 2 and 3, respectively. Groove 5
The roller 5 and the heads 2 and 3 are lubricated between the opposing surfaces of the roller 5 and the heads 2 and 3, and in such a case, the lubricating performance is insufficient due to the use of the refrigerant accompanying the alternative CFC. Even when oil is used, the oil groove 53 can reliably supply oil to the opposite surfaces.

In each of the above embodiments, the case where the invention is applied to the swing type compressor has been described. However, in the present invention, for example, the reciprocating blade comes into contact with the roller 5 inserted into the eccentric portion 41. It goes without saying that the roller 5 can also be applied to a compressor of the type in which the roller 5 is revolved while rotating in the cylinder chamber 11.

[0034]

As described above, according to the invention described in claim 1, the height of the sliding portion S between the eccentric portion 41 of the drive shaft 4 and the roller 5 is equal to or higher than the height of the cylinder 1. Therefore, the height of the roller 1 is increased while keeping the height of the cylinder 1 unchanged, so that the projected area (Λ) of the bearing can be increased without impairing the compression efficiency. The load per unit (P value) applied to the eccentric part is reduced, and the PV value applied to the eccentric part is reduced.
The reliability of No. 1 can be improved.

According to the second aspect of the present invention, the respective heights of the roller 5 and the eccentric portion 41 at the insertion portions are:
The height of the sliding portion S can be made equal to or higher than the height of the cylinder 1 only by making a simple design change so that the height is equal to or higher than the height of the cylinder 1.

According to the third aspect of the present invention, the eccentric portion 41 is set to a height of the cylinder 1 or more, and the fixed bush 8 having a height of the cylinder 1 or more is provided on the inner peripheral side of the roller 5. By inserting and fixing, the contact area between the roller 5 and the eccentric portion 41 is increased through the fixing bush 8 to reduce the PV value. Therefore, the roller 5 is separately processed. The initial purpose can be achieved with a simple structure using the fixed bush 8 without performing the above.

According to the fourth aspect of the present invention, the eccentric portion 41 is set to be higher than the height of the cylinder 1, and the floating distance higher than the height of the cylinder 1 is provided between the eccentric portion 41 and the roller 5. Since the bush 9 is slidably interposed, the roller 5 is moved to the cylinder chamber 11 as the eccentric portion 41 rotates.
When driven to rotate inside, the eccentric portion 41 and the roller 5 are
And the floating bush 9 is relatively rotating with respect to the roller 5 and the eccentric portion 41 while sliding.
Since the roller 5 and the eccentric part 41 follow and rotate at an intermediate speed v, which is slower, the floating bush 9 has a lower V value than the roller 5, and the eccentric part 5 has the floating bush. 9 and the height of the eccentric part 41 are equal to or higher than the height of the cylinder 1, the contact area between them and the projected area of the bearing are increased, and the P value is decreased. The PV value between the bush 9 and the eccentric portion 41 and the roller 5 can be reduced, and therefore,
The PV value applied to the eccentric portion can be reduced and the reliability of the shaft portions 4 and 41 can be improved with a simple configuration in which the floating bush 9 is added without separately processing the roller 5. it can.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a main part of a first embodiment of the present invention.

2 is an end view taken along the line AA in FIG.

FIG. 3 is a longitudinal sectional view of a main part of a second embodiment of the present invention.

FIG. 4 is a longitudinal sectional view of a main part of the second embodiment.

FIG. 5 is a longitudinal cross-sectional view of a main part of the second embodiment.

FIG. 6 is a vertical cross-sectional view of a main part of a third embodiment of the present invention.

FIG. 7 is a plan sectional view of a main part of a rotary compressor according to the present invention.

FIG. 8 is a vertical cross-sectional view showing the entire structure of a conventional rotary compressor.

FIG. 9 is a sectional view of a main part of a conventional rotary compressor.

[Explanation of symbols]

 1 ... Cylinder 11 ... Cylinder chamber 2 ... Front head 3 ... Rear head 4 ... Drive shaft 41 ... Eccentric part 42 ... Outer peripheral surface 5 ... Roller 8 ... Fixed Bush 9 ・ ・ ・ Floating bush S ・ ・ ・ Sliding part

Claims (4)

[Claims] 1. A cylinder (1) defining a cylinder chamber (11), and a front head (2) and a rear head (3) arranged at an end of the cylinder (1), the cylinder chamber (11) being provided. ) In which a roller (5) inserted into the eccentric part (41) of the drive shaft (4) is installed, a sliding part (S) between the roller (5) and the eccentric part (41) is provided. ) Is higher than the height of the cylinder (1), the rotary compressor. 2. The rotary compressor according to claim 1, wherein the height of each of the roller (5) and the insertion portion of the eccentric portion (41) is equal to or higher than the height of the cylinder (1). 3. A cylinder (1) is provided on the inner circumference of the roller (5).
The height of the outer peripheral surface (42) of the eccentric part (41), which fixes a cylindrical fixed bush (8) higher than the height of the cylinder, and receives the fixed bush (8) in a slidable and slidable manner, The rotary compressor according to claim 1, wherein the height is not less than the height of (1). 4. The cylinder (1) is provided on the inner circumference of the roller (5).
A cylindrical floating bush (9) higher than the height of the eccentric part (41) is slidably and slidably inserted, and the outer peripheral surface (4) of the eccentric part (41) that receives the floating bush (9) slidably and slidably
The rotary compressor according to claim 1, wherein the height of 2) is equal to or higher than the height of the cylinder (1).