JPH04116285A - Rotary compressor - Google Patents

Abstract

PURPOSE:To improve the volume efficiency and improve the performance index by providing an intermediate pressure system controlling the pressure in a back pressure chamber at the intermediate pressure between the low pressure and the high pressure, and setting the thickness of a vane to the thickness determined by the preset equation. CONSTITUTION:A vane 24, a back pressure chamber 25 surrounded by the back face of the vane 24 and the main bearing and auxiliary bearing of a cylinder 21, and an intermediate pressure system controlling the pressure in the back pressure chamber 25 at the intermediate pressure Pd' between the low pressure Ps and the high pressure Pd are provided, and the thickness T of the vane 24 is set to the thickness determined by the equation I. The thickness T of the vane 24 is made thicker, the pressure in the back pressure chamber 25 is decreased, the pressing force on the back face of the vane 24 is made equal to that in the past, the leakage from the end face of the vane 24 is decreased by the increased quantity of the thickness T of the vane 24, and the volume efficiency is improved. The contact load between the vane 24 and a roller 8 is equal to that in the past, the volume efficiency is improved, thus the performance index can be improved.

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 improved volumetric efficiency and performance.

Conventional technology A conventional configuration will be explained using FIGS. 5 to 7.

1 is a rotary compressor with a sealed casing 2. electric motor section 3. The electric motor section 3 and the compressor section 4 are connected via a shaft 6. The shaft 6 consists of a main shaft 5a, a sub-shaft sb, and a crank 6c, and a rotor e of the electric motor section 3 is connected to one end of the main shaft 5a.

The compressor section 4 still includes a cylinder 7, rollers 8 . Vane 9
．． It is composed of a main bearing 1o and a sub-bearing 11. The vane 9 reciprocates within the groove 7a of the cylinder 7 in conjunction with the movement of the roller 8. 12 is a nupling provided on the back side of the vane. Reference numeral 13 denotes a compression section, which is located within the cylinder 7 and is composed of a main bearing 10° and a sub-bearing 11. Furthermore, the compression section 13 includes a roller 8 that is fitted into the crank 5C of the shaft 6 and rotates eccentrically, and a vane 9 that comes into contact with the roller 8.
It is partitioned into a suction chamber 13a and a compression chamber 13b.

14 is a suction pipe, and 16 is a discharge pipe. The suction pipe 14 communicates with the suction hole 16 of the cylinder 7 via the sub-bearing 11, and the discharge pipe 16 is still open into the sealed casing 2. Further, 17 is a discharge hole, and a compression chamber 13b is connected via a discharge valve 18.
The inside of the sealed casing 2 is communicated with the inside of the sealed casing 2. Reference numeral 19 denotes lubricating oil provided at the bottom of the sealed casing.

The operation of the compressor configured as above will be described below with respect to the flow of refrigerant gas.

A low temperature, low pressure refrigerant gas from a refrigeration system (not shown) is transferred to suction pipe 14. It is guided through the suction hole 16 and reaches the suction chamber 13a inside the cylinder T. The refrigerant gas that has reached the suction chamber 13a is
The air is gradually compressed by the rotational movement of the shaft 5 as the electric motor unit 3 rotates, and is continuously sent from the suction hole 16 to the discharge hole 17.

The compressed refrigerant gas is discharged through the discharge hole 17. It is discharged through the discharge valve 18. The discharged high-temperature, high-pressure refrigerant gas fills the sealed casing 2 and is discharged to the cooling system via the discharge pipe 13.

Here, the pressure on the back side of the vane 9 that partitions the inside of the cylinder 7 into the suction chamber 13a and the compression chamber 13b is the same high pressure as the discharge pressure because it is opened in the sealed casing, and the tip of the vane 9 is placed in the cylinder 7. Due to the pressure difference between the inside and outside, it comes into contact with the outer periphery of a roller 8 that rotates eccentrically in a cylinder 7 by a shaft 6.

FIG. 7 shows the relationship between vane thickness and performance based on experiments conducted by the inventor. Figure 7 shows that if the width of the vane is increased in order to reduce leakage from the end face of the vane 9 and improve volumetric efficiency, the pressing force from the rear surface of the vane will increase, the contact load between the vane and the roller will increase, and the sliding loss will occur. increases and the input increases. Also, in order to reduce sliding loss, if the thickness of the vane is made thinner,
Leakage from the vane end faces increases and volumetric efficiency deteriorates.

For this reason, in rotary compressors for refrigeration and refrigeration, the optimum values of these characteristics are currently set, and the vane thickness is set to around 3 mm.

In order to improve performance, it is possible to increase the thickness of the vane without increasing the vane back pressure load.

Problems to be Solved by the Invention In the above configuration, in order to improve the volumetric efficiency, if the vanes are made thicker, the back pressure load received on the back surface of the vanes becomes larger, and the sliding loss between the vanes and the rollers increases. However, the problem was that it was difficult to improve performance.

The present invention is intended to solve the above problems, and aims to improve the volumetric efficiency and the performance index by increasing the thickness of the vanes.

Means for Solving the Problems In order to solve the above problems, the rotary compressor of the present invention includes a sealed casing, a cylinder housed in the sealed casing, a main bearing and a sub bearing fixed to both ends of the cylinder. A shaft that is rotatably housed in a main bearing and a sub-bearing and has a crank; a roller that is fitted into the crank of the shaft and rotates eccentrically within the cylinder; and a roller that moves reciprocally within the groove of the cylinder and comes into contact with the roller to rotate the inside of the cylinder. A vane that is divided into a suction chamber and a compression chamber, a back pressure chamber surrounded by the back of the vane, a cylinder, a main bearing, and a sub bearing, and the pressure inside the back pressure chamber is set to an intermediate pressure Pd' between a low pressure P8 and a high pressure Pd. The vane has a thickness T of 3≦T0≦3.2 [drunk].

Effect The present invention has the above-described configuration, so that even if the thickness T of the vane is increased, the pressing force on the rear surface of the vane can be made equal to that of the conventional one by lowering the pressure in the back pressure chamber. Leakage from the end faces is reduced and volumetric efficiency can be improved.

Therefore, the contact load between the vane and the roller is the same as in the conventional case, and the volumetric efficiency is improved, so that the figure of merit can be improved.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 and 2. Incidentally, the same reference numerals as in the conventional example and the →-leg →comfort-parts are given the same reference numerals, and detailed explanations will be omitted.

2o is an intermediate pressure mechanism, which includes a cylinder 21 and a main bearing 22.
Secondary bearing 23. It is composed of page 724 and page 25
is a back pressure chamber provided on the back surface of the vane 24. Furthermore, in order to constitute an intermediate pressure mechanism, the main bearing 22 is provided with a first oil passage 22a and a third oil passage 22b, and
The vane 24 is also provided with a second oil passage 24a. These oil passages 22a, 22b, and 24a are all in communication when the vane 24 is near the top dead center A of the crank rotation angle θ=0 or 2π as shown in FIG. 4, and as shown in FIG. As shown, the vane 24 is at the bottom dead center B of the crank rotation angle θ=π
When the hole is near the hole, the hole is opened so that there is no communication between all the holes.

In addition, the thickness T of the vane is the low pressure (suction pressure) PR2
High pressure (discharge pressure) Pd, pressure inside the back pressure chamber 26 Pd
If it is 2, then 3kuTo<, 3.2 (fin).

The operation of the rotary compressor configured as above will be described below.

The low-temperature, low-pressure refrigerant from the cooling system is passed through the suction pipe 14 as before. The suction chamber 13a in the cylinder 21 is reached through the suction hole 16. The refrigerant GANU is conventionally compressed and discharged to the υ system via discharge pipe 16.

Also, to explain the intermediate pressure mechanism 20, when the vane 24 reaches the top dead center, the lubricating oil 19 at the bottom of the sealed casing 2
The back pressure chamber 26 is connected to the oil passage 22&.

High-pressure lubricating oil 19 flows into the back pressure chamber 26 through communication via 22b and 24a. While the vane 24 is sliding back and forth, the vane 24 leaks into the suction chamber 13a and the compression chamber 13b.
It lubricates and seals between the cylinder 21 and the cylinder 21.

After inhaling high-pressure lubricating oil near top dead center A, vane 24
While the back pressure chamber 25 moves from top dead center A to bottom dead center B, the back pressure chamber 25 does not communicate with the lubricating oil 19 at the bottom of the sealed casing 2, and the back pressure chamber 25
, the pressure in the back pressure chamber 25 decreases and becomes an intermediate value PM between the high pressure Pd and the low pressure P8, and then during the movement from bottom dead center B to top dead center A, the lubricating oil 19 also Since there is no communication and the volume of the back pressure chamber 26 decreases, the pressure in the back pressure chamber 25 rises again and becomes high pressure.

Therefore, the average intermediate pressure Pd' of the back pressure chamber 26 is a value between the high pressure Pd and the intermediate value PM.

Since the pressure on the back surface of the vane 24 can be lowered by the intermediate pressure mechanism 20, even if the thickness T of the vane 24 is increased, the pressing force on the back surface of the vane 24 can be controlled to the same level as before, and the sliding loss is also the same as before. Moreover, the leakage from the end face of the vane 24 is reduced by the increase in thickness of the vane compared to the conventional one, and the volumetric efficiency can be improved. Therefore, it is possible to improve the performance index of the rotary compressor.

In this embodiment, the intermediate pressure mechanism is disclosed in Japanese Patent Application Laid-Open No. 61-1
No. 06992 was used, but any other method may be used.

Effects of the Invention As described above, the present invention includes a sealed casing, a cylinder housed in the sealed casing, a main bearing and a sub-bearing fixed to both ends of the cylinder, and a main bearing and a sub-bearing rotatably housed in the main bearing and sub-bearing. a shaft having a crank; a roller that is fitted into the crank of the shaft and rotates eccentrically within the cylinder; a vane that reciprocates within a groove of the cylinder and comes into contact with the roller, dividing the inside of the cylinder into a suction chamber and a compression chamber;
A back pressure chamber surrounded by the back side of the vane, the cylinder, the main bearing, and the sub bearing, and the pressure inside the back pressure chamber are defined as low pressure Ps and high pressure Ps.
, and an intermediate pressure mechanism that controls the vane thickness T to an intermediate pressure Pd' of Pd-P.

T = -1111-xT P d/ -P , 0 However, since 3≦T0≦3.2 [silk], even if the thickness of the vane is made thick, the load received from the back of the vane can be reduced. The intermediate pressure mechanism allows the same pressure as before, and the sliding loss between the roller and vane is also the same as before, and the thicker wall thickness of the vane reduces leakage from the end face of the vane, improving volumetric efficiency. This makes it possible to realize an excellent compressor that can further improve the performance index.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a rotary compressor showing an embodiment of the present invention, Fig. 2 is a longitudinal sectional view of the rotary compressor shown in Fig. 1, and Figs. 3 and 4 show an intermediate compressor. FIG. 5 is a cross-sectional view of a conventional rotary compressor, FIG. 6 is a vertical cross-sectional view of a conventional rotary compressor, and FIG. 7 is a graph showing the relationship between vane thickness and performance. 2... Sealed casing, 5... Shaft, 5c... Crank, 6... Roller, 13a... Suction chamber, 13b... ... Compression chamber, 20 ... Intermediate pressure mechanism, 21 ... Cylinder, 22 ... Main bearing, 23 ... Sub-bearing, 24 ... ...Vane, 25...Back pressure chamber. Name of agent: Patent attorney Akira Okaji and two others Middle pressure cylinder Main bearing 21 shaft Bow back pressure chamber 20-m-Medium closed 2I-Series 22-Main shaft 23--1 Offset shaft 24- Go to 25- Back Pressure Reception Room Plan 1

Claims (1)

[Scope of Claims] A sealed casing, a cylinder housed in the sealed casing, a main bearing and a sub-bearing fixed to both ends of the cylinder, and a crank rotatably housed in the main bearing and sub-bearing. a shaft having a shaft, and a roller that is fitted into a crank of the shaft and rotates eccentrically within the cylinder;
A vane that reciprocates in a groove of the cylinder and comes into contact with the roller to divide the inside of the cylinder into a suction chamber and a compression chamber, and is surrounded by a back surface of the vane, the cylinder, the main bearing, and the auxiliary bearing. The pressure inside the back pressure chamber is set to an intermediate pressure P_ between the low pressure P_s and the high pressure P_d.
d', and the thickness T of the vane is T=(P_d-P_s/P_d'-P_s)×T_o, where 3≦T_o≦3.2 [mm]. rotary compressor.