JPH03271591A - Rotary compressor - Google Patents

Abstract

PURPOSE:To reduce the leakage loss, and improve the volumetric efficiency and reliability by providing channels in end faces opposite to a main bearing and an auxiliary bearing of an inside roller divided into two in the axial direction, and providing a spring between end faces of the inside rollers opposite to each other. CONSTITUTION:Inside rollers 36, 37 are housed freely to rotate with a crank 3c, which is eccentric from the center of a shaft 3, to be revolved, and while is rotated with a touch on an outside roller 5b abutting on a vane. Consequently, the lubricating oil 18 is efficiently flowed into channels 28, 32 and 20, 24 provided on end faces 36a, 37a opposite to a main bearing 7 and an auxiliary bearing 8 of the inside rollers 36, 37. As a result, the hydraulic force of the end faces 36a, 37a are balanced through a spring 19, and a clearance deltaa between one inside roller 36 and the main bearing 7 and a clearance deltab between the other inside roller 37 and the auxiliary bearing 8 are held at positions with a clearance division deltaa=deltab of which leakage is minimum.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a rotary compressor used in a refrigeration cycle or the like, and particularly relates to a configuration with good volumetric efficiency and improved efficiency by reducing mechanical loss.

Prior Art A conventional configuration will be explained with reference to FIGS. 4, 5, and 6.

1 is a sealed casing, 2 is an electric motor section, and shaft 3
via cylinder 4. Inner roller 5a.

Outer roller tsb, vane 6, main bearing 7. It is connected to a mechanical part main body 9 constituted by a sub-bearing 8.

The shaft 3 consists of a main shaft 3a, a sub-shaft 3b, and a crank 3c. Further, a hole 3e is formed in the center of the shaft 3, and an oil supply hole sf and an oil supply groove 3q are provided in the oil supply hole 3c of the crank 3c.

10 is a spring provided on the back side of the vane.

11 is inside the cylinder 4, an inner roller 5a, an outer roller s
b, vane 6, main bearing 7. This is a compression chamber formed by the sub-bearing 8. 12 is an oil supply mechanism connected to the shaft 3. 13 is a suction pipe fixed to the sub-bearing 8, and is a suction passage 14a of the sub-bearing 8.

It communicates with the compression chamber 11 via the suction passage 14b of the cylinder 4. 15 is a discharge hole (not shown) and a discharge valve 16
(not shown) communicates with the inside of the sealed casing 1. Reference numeral 17 denotes a discharge pipe that opens into the sealed casing 1. 18 is lubricating oil.

The electric motor section 2 is composed of a rotor 2a and a stator 2b, and the rotor 2a has a balance way 2c.

2d is fixed.

Refrigerant gas from the cooling system (not shown) is supplied to the suction pipe 1
3. The suction passages 14a and 14b lead to the compression chamber 11 within the cylinder 4. The refrigerant gas that has reached the compression chamber 11 is partitioned by the outer roller 5b fitted onto the inner roller 6 fitted to the crank 3C of the shaft 3 and the vane 6, where it is rotated by the rotation of the electric motor section 2. accompanying shaft 3
It is gradually compressed by the rotational movement of the inner roller 5a and outer roller 6b. Therefore, during compression, the high pressure chamber 11
A and a low pressure chamber 11b are present.

The compressed refrigerant gas is discharged through the discharge hole 1 provided in the sub-bearing 8.
5. The liquid is once discharged into the sealed casing 1 through the discharge valve 16 and then discharged through the discharge pipe 17 to the cooling system.

The lubricating oil 18 is supplied to the shaft 3 and the main bearing 7 by the oil supply mechanism 12. The lubricating oil 18, which is supplied to the sliding parts such as the secondary bearing 8, reaches the shaft 3 through the oil supply hole sf of the crank 3C,
The oil supply groove 3q fills the inner peripheral surface 5C of the inner roller 6a. Furthermore, the lubricating oil 18 on the inner circumferential side of the inner roller 6a is applied to the upper and lower end surfaces 41 a and 41 b of the inner roller 5 a and the upper and lower end surfaces 38 a of the outer roller 5 b due to the differential pressure between the inner circumferential side of the inner roller 5 a and the compression chamber 11. , 38b and both bearings 7, 8
It flows into the compression chamber 11 through the gap between them and lubricates the sliding parts inside the cylinder 4.

Therefore, compared to the case where there is only one roller, the outer roller 6b
Since the relative speed between the vane 6 and the inner roller 5a and the crank 30 of the shaft 3 are reduced, sliding loss can be reduced.

For example, it is shown in Japanese Patent Application Laid-Open No. 60-92791.

Problems to be Solved by the Invention However, in the above configuration, the amount of lubricating oil containing refrigerant leaking into the compression chamber from the gaps between the inner and outer rollers, the main bearing, and the sub-bearing is determined by the gap length l. Therefore, during operation, the flat end surfaces of the inner and outer rollers are in contact with one side of the main bearing or the sub-bearing, and the inner and outer rollers are often inclined with respect to the bearing plane.

Due to distortion of the cylinder end faces when assembling the housing, cylinder, and bearings, the clearance between each end face of the inner and outer rollers and the end faces of both bearings must not be larger than necessary to ensure reliability. (for example, about 10 μm for refrigerators), the amount of lubricating oil containing high temperature and high pressure refrigerant leaks is large.
It had the disadvantages of low volumetric efficiency and poor compression efficiency.

Furthermore, since the height of the inner and outer rollers is constant during operation, and the sum of the gaps between them and both bearings is also constant, depending on processing accuracy and assembly distortion, small gaps may occur locally, causing local wear. There were reliability issues.

Both end surfaces of the inner roller and outer roller are supplied with oil by the differential pressure between the high pressure on the inner circumference side of the inner roller and the pressure in the middle of compression on the outer part of the outer roller. Since the sliding portion between the inner circumferential portions of the rollers is not lubricated by differential pressure, etc., there have been problems with reliability such as decreased efficiency of the compressor due to increased sliding loss and seizure of the rollers.

The present invention solves the above-mentioned drawbacks of the conventional example, and aims to reduce the amount of lubricating oil flowing into the suction chamber and compression chamber from the gap between the roller and both bearings during compressor operation, and The purpose is to reduce sliding loss and improve compressor efficiency and reliability.

Means for Solving the Problems The present invention provides a structure in which an inner roller divided into two parts in the axial direction is formed with a communication part with the inner peripheral part of the inner roller and a sealing part on the end face facing the main bearing and the sub-bearing. The inner roller is provided with a spring between opposing end surfaces of the inner roller, which is divided into two parts.

Operation The present invention has the above-described configuration, and the inner roller and outer roller, which are rotatably housed in a crank eccentric from the center of the shaft, rotate around the sun and rotate by contact with the vanes. Therefore, as the inner roller moves, lubricating oil flows into the grooves formed on both end faces facing both bearings of the divided inner roller, and pressure is generated as it reaches the sealing part. do.

As a result, when the clearance δ8 between one of the two divided inner rollers and the main bearing is not equal to the clearance δb between the other inner roller and the sub-bearing, this hydraulic pressure becomes unbalanced, and the two inner rollers The inner roller is reliably held at a position where the hydraulic pressure is balanced, that is, at a position where δ8=δb, through a spring between the inner rollers. Furthermore, clearance δ8. When δb decreases, the hydraulic pressure increases and the inner roller moves in the direction of increasing clearance, and when the clearance δ1δb increases, the hydraulic pressure decreases and the inner roller moves in the direction of decreasing clearance. Clearance δ, regardless of accuracy
By providing the flexibility of the inner roller to move so that δb remains approximately constant, the clearance δ8. δb is minimized.

Therefore, the amount of lubricating oil flowing into the suction chamber and compression chamber through the gap between the inner roller and both bearings is reduced, and wear of the inner roller can also be reduced, improving reliability.

A suitable gap is secured by a spring on the opposing end surfaces of the inner rollers, which are divided into two parts, so lubricating oil is supplied to the entire circumference between the inner roller and the outer roller through this gap. , the sliding loss between the inner and outer rollers can be reduced.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1, 2, and 3. Incidentally, the same parts as in the conventional example are given the same reference numerals, and the description thereof will be omitted. Further, the arrow in the figure indicates the direction of rotation of the shaft.

36.37 is an inner roller rotatably interposed in the crank 3c of the shaft 3, and 5b is an inner roller 36.3.
7 is an outer roller rotatably fitted. A spring 19 is fixed between both end surfaces 36b and 37b of the inner rollers 36 and 37.

Also, an end surface 37a of the inner roller 37 facing the sub-bearing 8
and grooves 20 to 24 to 27 and grooves 28 to 32 to 3, respectively, on the end surface 36a of the inner roller 36 facing the main bearing.
6 are provided in the same number. The grooves 2o to 35 are communication portions 2 with the inner peripheral portions 36c and 37c of the inner rollers 36 and 37.
0a to 35a, and sealing portions 20b to 3tsb
has. Further, the grooves 20 to 35 are connected to the communication portions 20a to 35a.
to the sealing portions 20b to s6b in the direction of rotation of the inner rollers 36,37.

In the above configuration, when the button is pressed during compressor operation, the inner rollers 36 and 37 are moved by the crank 3 which is eccentric from the center of the shaft 3.
It is rotatably stored in C, and as it revolves,
The vane 6 rotates due to contact with the outer roller 6b. That is, the locus of one point on the inner roller 36.3T is not circular but spiral. Therefore the inner roller 36.3
7 main bearing 7. End faces 36a, 37 facing the secondary bearing 8
The lubricating oil 18 efficiently flows into the grooves 28 to 35 and 20 to 27 provided on the grooves 28 to 35 and 20 to 27 from the inner peripheral surfaces 36c and 37c of the inner rollers 36 and 37 via the communicating portions 28a to 35a and 20a to 27a. . And inner roller 36.37
As the lubricating oil 18 moves, the pressure increases due to the wedge effect while the lubricating oil 18 reaches the sealing parts 28b to 35b and 20b to 27b. As a result, the hydraulic pressure between the end surfaces 36a and 37a is balanced, and the clearance δ8 between the two divided inner rollers 36 and the main bearing 7 and the clearance δb between the other inner roller 37 and the sub-bearing 8 are adjusted to prevent leakage. It is held at the position of δ8=δb, which is the smallest clearance distribution. For example, if the clearances δ8 and δb are not equal, δ8>δb
When , the hydraulic pressure generated at the end face 37a is
The hydraulic pressure generated at 6a is also large, so the spring 19 between the inner rollers 36 and 37 is compressed, and the inner roller 36 is pushed toward the main bearing 7 by the spring force.
The clearance δ6 becomes smaller, and the hydraulic pressure generated at the end face 36a increases. Then, the position where the hydraulic pressure generated at both end surfaces 36a and 37a is balanced, that is, both end surfaces 36a,
The inner rollers 36 and 37 are reliably held at the position of δ6=δb, which is the distribution in which the amount of lubricating oil leaking from 37a to the suction chamber 11b and the compression chamber 11a is the smallest.

Further, as the clearance δ1δb decreases, the hydraulic pressure increases and the inner rollers 36, 37 move in the direction of increasing the clearance, and as the clearance increases, the hydraulic pressure decreases and the inner rollers 36, 37 move in the direction of decreasing the clearance. It is reliably held in a position balanced with the force of the spring 19. Therefore, the inner rollers 36 and 37 have the flexibility to move so that the clearance δ1δb remains approximately constant regardless of assembly distortion and processing accuracy. Can be set to . Therefore, the clearance δ.

δゎ can be kept to a minimum. As a result, the lubricating oil containing refrigerant leaking into the compression chamber 11 through the gaps between the end faces 35a, 37a and both bearings 7, 8 can be reduced to a minimum in the housing, and the volumetric efficiency can be improved. Local wear of the inner rollers 36, 37 is eliminated, improving reliability.

Furthermore, the clearance δ between both end surfaces 36b and 37b of the inner surface rollers 36 and 37 is ensured by the spring 19. Since lubricating oil flows between the outer circumferential surfaces of the inner rollers 36 and 37 and the inner circumferential surface of the outer roller 6b due to centrifugal force and differential pressure, sufficient oil can be supplied over the entire circumference of the inner rollers 36 and 37 and the outer roller 6b. 6b opening sliding loss can be reduced, compressor efficiency can be improved, and seizure can also be prevented.

The outer circumferential side of the inner roller 36, 37 and the outer roller 6b
Since the clearance between the inner circumferential sides of
The pressure at points , 40 is not high pressure, but is 1 inch between the high pressure and the pressure in the compression chamber 11, as in the past, and the pressure difference between the inner and outer peripheral parts of the outer roller 5b is the same as in the past. Therefore, leakage from both end surfaces 38a and 38b of the outer roller 6b will also increase.

In this example, the width of the groove is changed from the communication part to the sealing part, and one sealing part is provided in the rotation direction of the inner roller for one communication part, but the cross-sectional area is changed. It is also possible to provide a plurality of sealing parts extending in the radial direction for one communication part (for example, by reducing the depth of the groove)! not.

Effects of the Invention As is clear from the above description, the present invention includes a cylinder, a main bearing fixed to the end face of the cylinder, a shaft that rotates and slides within the main bearing and the sub-bearing and has a crank, and a crank of the shaft. an inner roller that is rotatably housed in the inner roller and divided into two in the axial direction; an outer roller that is fitted onto the inner roller; A spring is provided between the plurality of grooves formed by the communicating portion and the sealing portion, and the opposing end surfaces of the divided inner roller, so that the end surfaces of the two inner rollers and the main bearing The clearance between the bearing and the auxiliary bearing can be kept uniform and minimized regardless of assembly distortion or processing accuracy, reducing leakage loss, improving volumetric efficiency, and improving reliability. Further, sufficient oil can be supplied over the entire circumference between the inner and outer rollers through the gap between the opposing end surfaces of the two inner rollers, and sliding loss can be reduced.

[Brief explanation of drawings]

FIG. 1 is an enlarged sectional view of the mechanical part of a rotary compressor showing an embodiment of the present invention, and FIG. 2 is a front view of the inner roller of the present invention.
Fig. 3 is a diagram showing the change in clearance and hydraulic pressure between the inner roller and both bearings, Fig. 4 is a vertical cross-sectional view of a conventional rotary compressor, and Fig. 5 is a diagram showing the change in the clearance and hydraulic pressure between the inner roller and both bearings. 6th arrow view
The figure is an enlarged sectional view of the mechanical part of FIG. 4. 3...Shaft, 3C...Crank,
4...Cylinder, 5b...Outer roller, 7...Main bearing, 8...Sub bearing, 19
・・・・・・Spring, 20~24~27.28~3
2-35...Groove, 20a-24a-27a
, 28a to 32a to 35a...Communication part, 2ob
~24b ~27b, 28b ~32b ~35b
. . . Sealing portion, 36. 37 . . . Inner roller, 36a. 37a...Inner roller end surface, 3eb, 37
b... Opposing end surface of inner roller, 36c, 3
7c...Inner circumference of inner roller.

Claims (1)

[Claims] A cylinder, a main bearing and a sub-bearing fixed to the end face of the cylinder, a shaft that rotates and slides within the main bearing and the sub-bearing and has a crank, and a shaft that is rotatably housed in the crank of the shaft and extends in the axial direction. An inner roller that is divided into two parts, an outer roller that is fitted onto the inner roller, and an end surface of the inner roller that faces the main bearing and the sub-bearing, respectively, has a communication portion with the inner circumference of the inner roller; A rotary compressor comprising a plurality of grooves formed by a sealing part and a spring between opposing end surfaces of the divided inner roller.