JPS59119081A - Scroll fluid machine - Google Patents

Abstract

PURPOSE:To prevent increase of the driving power caused by the distribution of hydraulic pressure around the outer peripheral portion of the end plate of a revolving scroll, by making the thickness of the end plate of the revolving scroll at its outer peripheral portion smaller than the mean thickness of the end plate. CONSTITUTION:The thickness HS1 of the end plate of a revolving scroll 2 at its outer peripheral portion 2f is made smaller than the mean thickness Hs of the end plate portion 2, and the end plate portion 2 of the revolving scroll is constituted in a stepped structure. Therefore, even if the revolving scroll 2 continues its revolution in a frame 4, it does not functions as a hydraulic pump since lubricating oil is allowed to flow freely at the stepped portion. Thus, it is enabled to prevent increase of the driving power caused by the distribution of hydraulic pressure around the outer peripheral portion of the end plate of the revolving scroll 2.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a scroll fluid machine used as a refrigerant compressor or an air compressor for refrigeration air conditioning, refrigerators, etc.

[Prior art]

Taking a scroll fluid machine as an example of a compressor for refrigeration and air conditioning, its basic configuration, lubrication method, etc. will be explained with reference to FIGS. 1 to 4. For ease of explanation, solid line arrows in FIG. 1 indicate the flow direction of working gas, and broken line arrows indicate the flow direction of lubricating oil.

FIG. 1 shows the overall structure of a conventional hermetic scroll compressor for air conditioners. The compressor includes both scroll members, a fixed scroll member 1 and an orbiting scroll member 2, which are compression element parts, an anti-rotation member 3 and a main shaft 6 that prevent the orbiting scroll 2 from rotating, three bearings that support the rotation, That is, it is comprised of a swing bearing 12, a main bearing 11, an auxiliary bearing 10, an electric motor 9, a stationary member 4 (hereinafter referred to as 1-frame) for fixing the fixed scroll 1, and the like. These components are housed inside the closed container 23. FIG. 1 shows an example of a high-pressure chamber type structure in which the inside of the closed container 23 is in an atmosphere of discharge pressure (high-pressure side pressure).

The operation of the compressor will be explained according to the flow of refrigerant gas and the flow of lubricating oil.

The low-temperature, low-pressure refrigerant gas is guided from the suction pipe 19 and reaches the suction chamber 1f in the fixed scroll 1. As shown in FIG. 2, the refrigerant gas that has reached the compression element part is caused by the orbital movement of the orbiting scroll, which is prevented from rotating, so that the closed spaces 5a and 5b formed by both scrolls gradually shrink, and the center part of the scroll is compressed. At the same time, the refrigerant gas increases its pressure and is discharged through the central discharge hole 1d. The discharged high-temperature, high-pressure refrigerant gas flows through the upper space 16 in the closed container 1 and the passage 1.
3.14, it fills the space 17 of the electric motor, and is led to the outside via the discharge pipe 20. (This high discharge pressure is indicated by the symbol Pd.) On the other hand, in a space 18 (referred to as a "back pressure chamber") surrounded by the back surface of the orbiting scroll member 2 and the frame 4, there are both orbiting and fixed scrolls. The suction pressure (low-pressure side pressure ) and the discharge pressure (denoted by the symbol pm) act. This intermediate pressure can be set by providing pores 2c and 2d in the end plate 2a of the orbiting scroll 2, and guiding the gas in the middle of the scroll to the back pressure chamber through the pores to apply gas force to the back surface of the orbiting scroll. conduct. The method of applying this intermediate pressure is described in JP-A-53-119412 and JP-A-55-37.
520, etc., so a detailed explanation will be omitted. In addition, in FIG. 2, A indicates the turning direction of the scroll member.

Next, the detailed structure of the anti-rotation member 3 is shown in FIGS. 3 and 4. An example of the anti-rotation member 3 configured with an Oldham ring 30 and Oldham pins 31 and 32 is illustrated. This Oldham ring 30 consists of an orbiting scroll 2 and a frame 4.
(Strictly speaking, the key pedestal 4a of the frame part) and the Oldham keys 31a, 31b provided respectively.
, 32a, 32b to prevent the orbiting scroll 2 from rotating. Therefore, there are 4 Oldham rings (33
, 34, 35, 36).

The circumferential structure of the outer peripheral portion 2f of the end plate of the orbiting scroll 2 will be explained with reference to FIGS. 5 to 7. The end plate part of the end plate part 2a of the orbiting scroll 2 is the end plate outer peripheral part 2f and the end plate central part 2.
The thickness is uniform regardless of j. In Fig. 6, this end plate is
Displayed in S dimensions. ). Also, orbiting scroll 2
The outer circumferential part 2f of the jump plate is the outer circumferential part 1 of the end plate of the fixed scroll 1.
C and the frame 40 and the pedestal 4b are sandwiched with a small gap maintained. In the case of FIG. 6, they are sandwiched with a small gap maintained. In the case of Figure 6, the minute gap is (Hr
Hs) (where Hf: top surface of frame 4
C) and the surface of the pedestal 4b). A radial oil supply passage 40 (for example, 408.4
0b, etc.) and oil supply holes 41 (for example, 418.41b, etc.).

These oil supply holes 41 are engaged with nine oil grooves 42 provided in the end plate portion 1a of the fixed scroll 1. The outer peripheral part 2f of the end plate of the orbiting scroll 2 performs a turning movement between the outer peripheral part 1C of the end plate of the fixed scroll 1 and the pedestal 4b of the frame 4, centering on the frame center point (or the fixed scroll center point) Of. The positional relationship between the frame 4 and the orbiting scroll 2 is as shown in FIG. FIG. 7 shows a cross-sectional view of the frame 4. The frame 4 is provided with two key pedestals 4a each having a key groove 4f for attaching an Oldham key. 4e is a bolt hole for attaching the fixed scroll 1. In this way, the outer peripheral part 2 of the end plate of the orbiting scroll 2
In addition to the back pressure chamber 18 at the back of the orbiting scroll, a space 43 is formed around f by the outer circumferential portion 2f of the end plate, the outer circumferential portion 1C of the fixed scroll opposing the end plate, and the frame 4.

Hereinafter, this space 43 will be referred to as a "frame chamber."

Note that a structure in which the outer circumferential portion 2f of the end plate of the orbiting scroll 2 is sandwiched between the stationary member IC and 4 while maintaining a small gap is disclosed in Japanese Patent Application Laid-open No. 142902/1983, so the structure Explanation of purpose, effect, etc. will be omitted.

Next, the flow of lubricating oil will be explained using FIGS. 1, 5, and 6.

The lubricating oil 7 is stored in the lower part of the closed container 23.

The lower end of the main shaft 6 is immersed in the oil at the bottom of the container, and the upper part of the main shaft is provided with an eccentric shaft portion 6a, which engages with the orbiting scroll member 2, which is a scroll compression element portion, via an orbiting bearing 12. It matches. The main shaft 6 has an eccentric vertical hole 6b formed from the lower end of the main shaft to the upper end surface of the main shaft for supplying oil to each bearing section.

At the lower part of the eccentric shaft part 6a, a balance weight 8 is mounted on the upper part of the main bearing that faces the tip end surface of the orbiting scroll post part 2e.
It is formed to be engaged with and integrated with the main shaft 6. The lower end of the main shaft 6 immersed in the lubricating oil 7 is in an atmosphere of high discharge pressure Pd, while the rotation of the downstream swing bearing 12 is in an atmosphere of intermediate pressure Pm, so the pressure is (Pd-Pm). Due to the difference, the lubricating oil 7 at the bottom of the container rises inside the eccentric vertical hole 6b. Also, due to the rotation of the main shaft 6, the eccentric vertical hole 6
Centrifugal force acts on the oil in b, further increasing the amount of oil supplied to each bearing. In this way, oil supply to each bearing part is
This is done using eccentric hole lubrication method and differential pressure lubrication method. The lubricating oil 7 rising inside the eccentric vertical hole 6b is supplied to the auxiliary bearing 10 and the main bearing 11, and is also supplied to the upper space 25 of the eccentric shaft portion 6a (the bottom surface of the boss portion of the orbiting scroll boss portion 2e and the bottom surface of the eccentric shaft portion 6a). This space becomes a hydraulic chamber (hereinafter referred to as "hydraulic chamber" 25) at the gap between the upper end surface and the upper end surface. The lubricating oil in the oil cliff chamber 25 is at a pressure equal to the discharge pressure Pd, and as shown in FIG. 5 and FIG. The oil reaches an oil groove 42 provided in the outer peripheral portion 1C of the end plate of the fixed scroll via a radial oil supply path 40 and an oil supply hole 41. The lubricating oil that has reached the oil groove 42 reaches the frame chamber 43 or the suction chamber 1f inside the scroll. In addition, the swing bearing 12 and the main bearing 1
The lubricating oil that has reached 1 is drained into the back pressure chamber 18 through the respective bearing gaps.

The lubricating oil that has reached the back pressure chamber 18 lubricates the organ ring part 30 and the like, and then is injected into the working chamber formed by both scrolls 1 and 2 through the pores 2c and 2d, and then the scroll wrap. Inside, it is mixed with the refrigerant gas. Next, the lubricating oil is pressurized together with the refrigerant gas, and moves together with the refrigerant gas to the motor chamber 17 via the discharge hole 1d% discharge chamber 16 and the passages 13 and 14. The lubricating oil that has reached the motor chamber 17 has a large flow rate due to the large space, and falls to the bottom of the container due to its own weight. That is, the refrigerant gas and lubricating oil are separated in the motor room 17. The fallen lubricating oil is collected again at the bottom of the container and used to lubricate the valleys.

Next, problems of the prior art will be explained using FIGS. 5 to 8.

A frame chamber 43 is provided on the outer circumferential portion 2f of the springboard of the orbiting scroll 2.
is formed, and lubricating oil leaks into the frame chamber from the oil groove 42 or the back pressure chamber 18. The outer peripheral portion 2f of the end plate of the orbiting scroll 2 is the outer peripheral portion 1C of the end plate of the fixed scroll 1.
Since it is sandwiched between the frame chamber 43 and the frame 4 with a minute gap (for example, a gap of about 100 μm), the frame chamber 43 forms a kind of closed space. For this reason, the lubricating oil that has once entered the frame chamber 43 stagnates within the space, and the frame chamber is finally filled with lubricating oil. In this state, when the orbiting scroll 2 continues to orbit inside the frame 4, the orbiting scroll 2 acts as a hydraulic pump, and hydraulic pressure acts on the circumference D2g of the outer circumference of the orbiting scroll end plate, and as a result, the orbiting scroll 2 is rotated. The required driving power increases. FIG. 8 shows the distribution of hydraulic pressure acting on the circumference L2g of the outer circumferential part of the springboard of the swinging flow lever 2. Pf in the figure represents the fluctuating hydraulic pressure, and F on the other hand. and 0° is the resultant force of the hydraulic pressure induced by the hydraulic divider, and it determines the direction of the force. Using FIG. 8, the amount of increase T in required torque due to the action of the hydraulic pump of the orbiting scroll 2 is determined. is given by the following equation.

To=ε・HS−Fosin Oo−・concave curve, ＜
1) Here, Fo: Load in two-year unit (Kq/m>H3: End plate of orbiting scroll (m) ε: Radius of revolution (m) To: Increased torque (K9・m) (1) Formula As shown in the figure, the amount of increase in torque due to the fluctuation of the hydraulic pressure around the outer periphery of the rotating head plate is proportional to the head plate portion H5.

If the above-mentioned torque is generated in addition to the gas compression torque and the friction torque of the bearing section, Oldham ring, etc., there is a problem that the performance of the compressor, especially the total adiabatic efficiency, decreases.

[Purpose of the invention]

The present invention has been made in view of the above problems.
It is an object of the present invention to provide a scroll fluid machine that can suppress an increase in power induced by the hydraulic pressure distribution around the circumference 9 of the outer circumference of the spring plate of the orbiting scroll 2.

[Summary of the invention]

To achieve the above object, as explained in equation (1), the increase in power generated as a result of the oil pressure fluctuation at the outer circumference of the end plate of the orbiting scroll occurs in proportion to the thickness of the outer circumference of the end plate.

For this reason, in the present invention, the end plate portion of the outer periphery of the spring plate of the orbiting scroll is made thinner than the average thickness of the other end plate portions.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to FIGS. 9 to 11.

The end plate portion H81 of the end plate outer peripheral portion 2f of the orbiting scroll 2,
As shown in FIG. 9, the average thickness of the end plate portion 2 is also reduced, and the end plate portion 2 of the orbiting scroll has a stepped structure.

There is a relationship of tzゎchiH8□<H5・times of music (3).

As the orbiting scroll 2 rotates, the stepped portion 211 and the inner circumferential surface of the frame pedestal 4b approach each other, but in order to prevent them from coming into contact, the following dimensional space is provided between the orbiting scroll and the frame. It has constraints (see Figure 10).

DS□+2ε<Df2・・・・・・・・・・・・・・・
...Song...Song/Song/(2) Ds. -26〉Df2
・・・・・・・・・・・・・・・ Song・・・・ Song・Song (3) D. +2ε＜Df□・・・・・・・・・・
...... Song... Song... Song (4) D. −ri, 1<4ε・・・・・・・・・・・・・・・4・
...Song times (5) ls) 2・ε ...Song, song・・・・・・・-- Hit...Song times (6) Here, Dso
: External diameter of the orbiting scroll end plate D5□ : External dimension of the orbiting scroll stepped part 2h Dfz 'Inner diameter of the frame pedestal Dfl: Outer diameter of ls : Dimension of the stepped part of the orbiting scroll From formulas (5) and (6) above , the turning diameter (DR
It can be seen that it is necessary to form it with a width of =2×ε. Note that, Equation (5) is the end plate 2a of the orbiting scroll 2.

2f shows the conditions under which the frame 43 is always placed on the frame pedestal 4b. Inner peripheral surface 4g of frame 4
As a matter of course, the depth Hf1 is set smaller than the dimension of Hf of the conventional machine in accordance with the end plate portion H81 of the end plate outer peripheral portion 2f of the orbiting scroll 2. The increase in power induced by the hydraulic pressure distribution around the outer peripheral portion of the end plate of the orbiting scroll 2 can be suppressed as much as possible.

〔Effect of the invention〕

According to the present invention, a high-performance scroll fluid machine can be obtained because it is possible to suppress the increase in power caused by oil pressure fluctuations around the outer circumference of the end plate of the orbiting scroll. In addition, as a result, the springboard of the orbiting scroll can be made into a stepped structure, and the weight of the orbiting scroll can be significantly reduced.As a result, the weight of the orbiting scroll can be reduced, and in balance, the balance weight 8 can also be made smaller.・It can be made lighter, so
It also has the effect of making it possible to quantify the entire compressor.

[Brief explanation of the drawing]

Figures 1 to 8 are for explaining a conventional scroll compressor. Figure 1 is a vertical sectional view of a conventional hermetic scroll compressor, and Figure 2 is a horizontal sectional view showing the meshing state of the scrolls. , Figures 3 and 4 are a plan view and longitudinal sectional views showing the positional relationship between the Oldham ring and the Oldham key. Figures 5 and 6 are
The figures are a plan view and a vertical sectional view showing the structure around the outer circumference of the spring plate of the orbiting scroll, Fig. 7 is a plan view of the frame with the closed container broken, and Fig. 8 is the structure acting on the outer circumference of the end plate of the orbiting scroll. Figures 9 and 10 showing the situation of oil pressure distribution are for explaining one embodiment of the present invention. Figure 9 is a side view of the orbiting scroll according to the present invention, and Figure 10 is a side view of the It is a top view which shows the structure of the outer peripheral part of an end plate of the orbiting scroll of a figure. 1...Fixed scroll 1f...Fixed scroll end plate outer periphery 2...Orbiting scroll 2a...
・End plate of the orbiting scroll 2f... Outer circumference of the spring board of the orbiting scroll 4... Frame 4b... Frame pedestal 18... Back pressure chamber 43... Frame chamber 30... Oldham ring 3 boxes 1 Army W7 circle θ (9th r5

Claims (1)

[Claims] 1. The scroll member has a fixed scroll and an orbiting scroll, the pair of scroll members is composed of an end plate and a spiral wrap standing upright thereon, and both scroll members are engaged with each other with the wraps inside, A device in which one of the orbiting scrolls orbits so as not to apparently rotate on its own axis, moving the closed space formed by both scroll members from the outside to the center, reducing the volume and compressing the fluid. In a scroll fluid machine configured such that the outer periphery of the end plate of the orbiting scroll is sandwiched between the stationary member to be fixed and the end plate of the fixed scroll with a minute gap maintained, the thickness of the outer periphery of the end plate of the orbiting scroll is determined by the thickness of the end plate of the end plate of the orbiting scroll. A scroll fluid machine characterized by having a thickness thinner than the average thickness of the parts. 2. ``The part where the sharp plate thickness of the outer circumferential part of the end plate of the orbiting scroll is thinner than the average thickness of the other spring plate parts is radially at least the orbiting diameter (D=2Xε; DR is the orbiting diameter, and ε is the orbiting radius. 3. A scroll fluid machine according to claim 1, characterized in that the outer circumference of the end plate of the orbiting scroll always forms a side space of the outer circumference of the end plate of the orbiting scroll; Claim 1 characterized in that the dimensional relationship between the two satisfies Dso-2×ε>Df2 (here, D5o represents the outer diameter of the end plate of the orbiting scroll, and Df2 represents the inner diameter of the frame pedestal) so that they face each other. , the scroll fluid machine according to item 2.