JPH02191893A - Rotary compressor - Google Patents

Abstract

PURPOSE:To contrive the improvement of reliability and performance by providing the fourth communication path, with one and communicating with a back pressure chamber and with the other end communicating with the third communication path, and variably constituting flow resistance in a connection part between the third and fourth communication paths. CONSTITUTION:In a position of stopping a slider 21, the second space 20b communicates with a back pressure chamber 13 through the third and fourth communication paths 25, 26, but they are formed so as to determine resistance of the flow path in the stop position of the slider 21. And a pressure in the back pressure chamber 13 is determined by its inflow and outflow amounts but normally almost by a pressure reducing amount by the flow path resistance in an inflow side. Accordingly, by optimizing a position of the slider 21, deter mined by a high-low differential pressure, and a level of the flow path resis tance, the pressure in the back pressure chamber 13 can be always generated in an optimum value for an operative condition in that time, and the reduction of a sliding loss and the improvement of reliability can be contrived in all the operative conditions.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a rotary compressor used in a refrigeration cycle or the like, and particularly relates to a configuration with little sliding loss.

Conventional technology The conventional configuration is shown in Figs. 7, 8, 9, 1Q, and 1.
This will be explained using Figure 1.

1 is the sealed casing, 2 is the electric motor part, and shaft 3
via cylinder 4. Roller 6, vane 6, main bearing a,
It is connected to a mechanical part main body 9 constituted by a sub-bearing 8. The shaft 3 is a main shaft 3a.

The subshaft 3b and the crank 3c are the same. 1o is a spring provided on the back side of the vane. 11a, 11b within the cylinder 4, rollers 6. The vane 6, the main bearing 7, and the sub-bearing 8 form a suction chamber and a compression chamber. 12 is an oil supply mechanism connected to the shaft 3. Reference numeral 13 denotes a back pressure chamber which is composed of the rear surface of the vane 6 on the opposite side to the contact surface with the roller 6, the cylinder 4, the main bearing 7, and the sub-bearing 8. Further, the main bearing 7 is provided with a first oil passage 7a and a third oil passage 7b, and the vane 6 is also provided with a second oil passage 6a. These oil passages 7a, 7b.

6b, the base 76 is rotated at the crank rotation angle θ as shown in FIG.
When it is near the top dead center A of = 0.2π, everything is in communication, and as shown in Figs. 8 and 10, the pedal 76 is near the bottom dead center B of the crank rotation angle θ = π. In some cases, the holes are made so that they are not all connected.

14 is a suction pipe, secondary bearing 8. It communicates with the suction chamber 11a via the suction passage 16 of the cylinder 4. Reference numeral 16 denotes a discharge part, which is connected to the sealed casing 1 through a discharge valve (not shown).
It communicates with the inside. Reference numeral 17 denotes a discharge pipe that opens into the sealed casing 1.

18 is a lubricating oil into which refrigerant is partially dissolved.

Next, the compressor groove of the rotary compressor will be explained.

Refrigerant gas from the cooling system (not shown) is supplied to the suction pipe 14.
．． A suction chamber 11a inside the cylinder 4 led from the suction passage 16
leading to. The refrigerant gas that has reached the suction chamber 11a is transferred to the shaft 3
In a compression chamber 11b partitioned by a roller 6 rotatably housed in a crank 30 and a vane e, the compressor is gradually compressed by the rotational movement of the shaft 3 as the electric motor section 2 rotates.

The compressed refrigerant gas is discharged from the discharge section 16. After being once discharged into the closed casing 1 through the discharge valve, it is discharged through the discharge pipe 17 to the cooling system.

Next, the flow of the lubricating oil 18 into which a portion of the refrigerant is dissolved will be explained. The lubricating oil 18 is supplied to the shaft 3 and the main bearing 7 through an oil supply mechanism. Secondary bearing 8. After being sent to the sliding part between the rollers 6, a part of the refrigerant is directly returned to the lower part of the hermetic casing 1, and a part of it enters the compression chamber 11b, is discharged together with the refrigerant gas, and returns to the lower part of the hermetic casing 1.

Regarding the space between the vane 6 and the cylinder 4, when the vane 76 reaches the top dead center, the lubricating oil 18 at the bottom of the sealed casing 1 and the back pressure chamber 13 communicate with each other through the oil passages a, 7b, and 7a, and the back pressure chamber High pressure lubricating oil 18 flows into 13. While the vane 6 slides back and forth, it leaks into the suction chamber 11a and the compression chamber 11b, lubricating and sealing the space between the vane 76 and the cylinder 4.

By the way, after inhaling high pressure lubricating oil near top dead center A,
While the vane 6 moves from top dead center A to bottom dead center B, back pressure chamber B,
! : Since it does not communicate with the lubricating oil 18 at the bottom of the sealed casing 1 and the volume of the back pressure chamber 13 increases, the pressure in the back pressure chamber 13 decreases, and becomes an intermediate pressure PM between the high pressure Pd and the low pressure PB. Next, while moving from bottom dead center B to top dead center A, lubricant oil is 1
8 and the volume of the back pressure chamber 13 decreases, so the pressure in the back pressure chamber 13 rises again and becomes high pressure.

Therefore, the pressure in the back pressure chamber 13 fluctuates between the high pressure Pd and the intermediate pressure PM, but since it is greater than the limit pressure Pc at which the vane 6 and the roller 6 separate, the back pressure of the vane 6 is always kept at the high pressure Pd. Compared to the case where the contact load between the vane 6 and the roller 5 is reduced, sliding loss is reduced, and reliability is improved.

For example, it is shown in Japanese Patent Application Laid-open No. Sho e1-106992.

Problems to be Solved by the Invention In such a conventional configuration, the change in volume of the back pressure chamber at the top dead center and bottom dead center positions is small, and the pressure does not drop sufficiently to near the intermediate pressure Pu'Pc, reducing sliding loss. The problem was that the amount was very small. In addition, the pressure inside the back pressure chamber is determined only by the operating high pressure Pd. For example, even if the low pressure Ps is the same even if the high pressure Pd is the same, the back pressure chamber pressure will be almost the same even though the limit pressure PC will be different. There was a problem in that it was not possible to control the pressure inside the back pressure chamber to the optimum pressure.

The present invention solves the above-mentioned drawbacks of the conventional example, and improves reliability and performance by controlling the pressure in the back pressure chamber to the optimum pressure determined by the operating high pressure and low pressure conditions. The purpose is to

Means for Solving the Problems The present invention communicates a first space and a second space at both ends of a slider biased by a spring with lubricating oil at a low pressure and a high pressure, respectively, and a third space at both ends of a slider which is biased by a spring. The communication passage communicates with the fourth communication passage that communicates with the back pressure chamber through variable flow resistance.

According to the above-described structure, the stop position of the sys slider is determined by the spring force of the low pressure, high pressure and spring force during operation, and at this time, the stop position of the sys slider is determined by the spring force of the low pressure and high pressure during operation. The resistance of the flow path is also determined.

Therefore, the high pressure lubricating oil introduced into the second space is
and is introduced into the back pressure chamber via the fourth communication path, but at this time, the amount of flow into the back pressure chamber is controlled by the resistance, and the back pressure pressure is controlled to an optimal value.

Therefore, performance and reliability can be improved.

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

Note that the same parts as in the conventional example are given the same reference numerals and detailed explanations are omitted.

Reference numeral 19 denotes a main bearing sb, which holds the shaft 3 as in the conventional case. 20 is a slide groove provided in the main bearing 19.

Reference numeral 21 denotes a slider biased by a spring 22, which is slidably held within the slide groove, and partitions the inside of the Nufide groove into first and second spaces \20a and 20b. The first space 20a communicates with the suction passage 16 via the first communication passage 23. The second space 20b communicates with the high-pressure lubricating oil 18 via the second communication path 24. The slider 21 is provided with a third communication passage 26 , and the third communication passage 25 communicates with a fourth communication passage 26 that communicates with the back pressure chamber 13 . At this time, the third and fourth communication passages 25 and 26 are formed so that their overlapping areas are variable so that the multi-channel resistance is variable depending on the stop position of the slider 21. .

As before, the refrigerant gas is supplied to the suction pipe 14. Suction passage 16
After being sucked into the suction chamber 11a through the suction chamber 11a and compressed in the compression chamber 11b, the discharge portion 16. Sealed casing 1. It is discharged through the discharge pipe 17.

At this time, low-pressure refrigerant gas and high-pressure lubricating oil are introduced into the first and second spaces 20a and 20b through the first and second communication passages 23 and 24, respectively. Therefore,
The slider 21 stops at a point where this pressure difference and the force of the spring 22 are balanced. At the stop position of the slider 21, the second space 20b and the back pressure chamber 13 communicate with each other via the third and fourth communication passages 25 and 26; The flow path resistance is determined depending on the stop position of the lubricating oil 18, so that an appropriate amount of lubricating oil 18 flows into the back pressure chamber 13. The lubricating oil 18 that has flowed into the back pressure chamber 13 passes through the clearance between the bay 76 and the cylinder 4 to the suction chamber 11a and the compression chamber 1.
1b.

The pressure inside the back pressure chamber 13 is determined by the inflow and outflow amounts, but is usually determined by the amount of pressure reduction due to the flow path resistance on the inflow side. Therefore, by optimizing the position of the slider 21, which is determined by the pressure difference between high and low levels, and the magnitude of the flow path resistance, the pressure inside the back pressure chamber 13 can always be kept at the optimal value for the operating conditions at that time. It is possible to reduce sliding loss and improve reliability under all operating conditions.

In the case of this embodiment, for example, when the high pressure is the same and the low pressure is different, the higher the low pressure is, the more the slider 21 moves in the direction of making the second space 20b smaller. The electrical current area of the passage is wide, and the multi-channel resistance is reduced. Therefore, the amount of lubricating oil flowing into the back chamber 13 from the second space 20b increases.

That is, in the case of the same high pressure, the pressure inside the back pressure chamber increases as the low pressure increases, but this is because the pressure PC that causes chattering between the bay 76 and the roller 5 increases as the low pressure increases. By approaching optimal control, efficiency and reliability can be improved.

Effects of the Invention As is clear from the above description, 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 fixed to both ends of the cylinder. A shaft that is rotatably housed and has a crank, a roller that is fitted into the crank of the shaft and rotates inside the cylinder, and a roller that moves reciprocally within the groove of the cylinder and comes into contact with the roller. A vane to be divided, a suction passage and a suction pipe communicating with the suction chamber, a back pressure chamber surrounded by the back of the vane, the cylinder, the main bearing, and the sub bearing, a slide groove, and a spring that slides in the slide groove. a slider biased by the slider, first and second spaces partitioned by the slider within the slide groove, and the first space and the suction chamber.

or a suction passage, a first communication passage communicating with the suction pipe, and a second communication passage;
a second communication path that communicates the space with the lubricating oil in the sealed casing; a third communication path provided in the slider that communicates with the second space; one end communicating with the back pressure chamber and the other end communicating with the third communication path; Since the compressor is provided with a fourth communication passage that communicates with the communication passage through variable flow resistance, sliding loss is reduced and a compressor with high efficiency and reliability can be provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a back pressure chamber of a rotary compressor showing an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of a conventional rotary compressor.
Fig. 3 is a view taken along the line m-m' in Fig. 2, Fig. 4 is a sectional view of the conventional back pressure chamber at top dead center, and Fig. 5 is a sectional view of the conventional back pressure chamber at bottom dead center. FIG. 6 is a cross-sectional view at a point, and is a diagram of a conventional oil passage opening/closing situation and a change curve of back pressure chamber pressure. 1...Sealed casing, 3...Shaft, 3c...Crank, 4...Re-cylinder~, 6-Old...Roller, 6...・Bane, 8・
...Secondary bearing, 11a...Suction chamber, 11b
...Compression chamber, 14...Suction pipe, 16.
...Suction passage, 19...Main bearing, 2o...
...Slide groove, 20a, 20b...
First and second spaces, 21...Slider, 22
...Spring, 23.24. +26.26・
...First. Second. Third. Fourth communication path. Name of agent: Patent attorney Shigetaka Awano and 1 other person
・-1 -1c - 5-... tq --- J2,. 2Da, mb --- 斂閘pusinwashaftcrankrilinvrollervanesubbearingmainshaftdasride]1 ■ 1 and 夷 2 0 Space n, 24.2
5. a...-Horse 1. Atsushi 2 Han 3. 3rd y, 1M connecting path of Pagoda 4! J Figure Figure Figure 1c/2 3/2π 7c Crank tip angle θ (Pad)

Claims (1)

[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, a shaft rotatably housed in the main bearing and sub-bearing and having a crank, and the shaft. a roller that is fitted in a crank and rotates eccentrically within the cylinder; a vane that reciprocates within 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; A suction passage and a suction pipe that communicate with each other;
a back pressure chamber surrounded by the back surface of the vane, the cylinder, the main bearing, and the auxiliary bearing; a slide groove; a slider that slides within the slide groove and is biased by a spring; The first partitioned with a slider
and a second space, a first communication path that communicates with the first space and the suction chamber or suction passage, and a suction pipe, and a second communication path that communicates the second space with the lubricating oil in the sealed casing. and a third communication passage provided in the slider and communicating with the second space, and a fourth communication passage having one end communicating with the back pressure chamber and the other end communicating with the third communication passage, and A rotary compressor characterized in that flow path resistance at a connecting portion between the third and fourth communication paths is variable.